From e1830579102f036e9e558320a21990a9438ec9ef Mon Sep 17 00:00:00 2001 From: malaterre Date: Sun, 7 Nov 2004 14:28:54 +0000 Subject: [PATCH] ENH: Final -hopefully- change to jpeg lib. In order to match ITK structure, and be more cross plateform, reduce code redondency and improve compilation time --- gdcmPython/gdcm.i | 3 +- src/CMakeLists.txt | 15 +- src/gdcmJpeg12.cxx | 11 +- src/gdcmJpeg16.cxx | 12 +- src/gdcmJpeg8.cxx | 10 +- src/gdcmjpeg/12/CMakeLists.txt | 9 + src/gdcmjpeg/16/CMakeLists.txt | 9 + src/gdcmjpeg/8/CMakeLists.txt | 8 + src/gdcmjpeg/CMakeLists.txt | 119 ++ src/gdcmjpeg/COPYRIGHT.dcmtk | 258 +++ src/gdcmjpeg/README | 385 ++++ src/gdcmjpeg/README.GDCM.txt | 105 ++ src/gdcmjpeg/change.log | 217 +++ src/gdcmjpeg/filelist.doc | 239 +++ src/gdcmjpeg/install.doc | 1063 +++++++++++ src/gdcmjpeg/jaricom.c | 15 + src/gdcmjpeg/jcapimin.c | 280 +++ src/gdcmjpeg/jcapistd.c | 161 ++ src/gdcmjpeg/jcarith.c | 24 + src/gdcmjpeg/jccoefct.c | 455 +++++ src/gdcmjpeg/jccolor.c | 460 +++++ src/gdcmjpeg/jcdctmgr.c | 390 ++++ src/gdcmjpeg/jcdiffct.c | 410 ++++ src/gdcmjpeg/jchuff.c | 274 +++ src/gdcmjpeg/jchuff.h | 54 + src/gdcmjpeg/jcinit.c | 57 + src/gdcmjpeg/jclhuff.c | 602 ++++++ src/gdcmjpeg/jclossls.c | 78 + src/gdcmjpeg/jclossy.c | 76 + src/gdcmjpeg/jcmainct.c | 296 +++ src/gdcmjpeg/jcmarker.c | 678 +++++++ src/gdcmjpeg/jcmaster.c | 648 +++++++ src/gdcmjpeg/jcodec.c | 53 + src/gdcmjpeg/jcomapi.c | 106 ++ src/gdcmjpeg/jconfig.doc | 155 ++ src/gdcmjpeg/jconfig.h.in | 69 + src/gdcmjpeg/jcparam.c | 687 +++++++ src/gdcmjpeg/jcphuff.c | 848 +++++++++ src/gdcmjpeg/jcpred.c | 301 +++ src/gdcmjpeg/jcprepct.c | 354 ++++ src/gdcmjpeg/jcsample.c | 520 ++++++ src/gdcmjpeg/jcscale.c | 64 + src/gdcmjpeg/jcshuff.c | 662 +++++++ src/gdcmjpeg/jctrans.c | 421 +++++ src/gdcmjpeg/jdapimin.c | 401 ++++ src/gdcmjpeg/jdapistd.c | 275 +++ src/gdcmjpeg/jdarith.c | 24 + src/gdcmjpeg/jdatadst.c | 151 ++ src/gdcmjpeg/jdatasrc.c | 213 +++ src/gdcmjpeg/jdcoefct.c | 744 ++++++++ src/gdcmjpeg/jdcolor.c | 414 ++++ src/gdcmjpeg/jdct.h | 176 ++ src/gdcmjpeg/jddctmgr.c | 270 +++ src/gdcmjpeg/jddiffct.c | 400 ++++ src/gdcmjpeg/jdhuff.c | 321 ++++ src/gdcmjpeg/jdhuff.h | 229 +++ src/gdcmjpeg/jdinput.c | 347 ++++ src/gdcmjpeg/jdlhuff.c | 291 +++ src/gdcmjpeg/jdlossls.c | 94 + src/gdcmjpeg/jdlossy.c | 228 +++ src/gdcmjpeg/jdmainct.c | 512 +++++ src/gdcmjpeg/jdmarker.c | 1370 ++++++++++++++ src/gdcmjpeg/jdmaster.c | 460 +++++ src/gdcmjpeg/jdmerge.c | 402 ++++ src/gdcmjpeg/jdphuff.c | 675 +++++++ src/gdcmjpeg/jdpostct.c | 292 +++ src/gdcmjpeg/jdpred.c | 258 +++ src/gdcmjpeg/jdsample.c | 483 +++++ src/gdcmjpeg/jdscale.c | 120 ++ src/gdcmjpeg/jdshuff.c | 360 ++++ src/gdcmjpeg/jdtrans.c | 138 ++ src/gdcmjpeg/jerror.c | 252 +++ src/gdcmjpeg/jerror.h | 306 +++ src/gdcmjpeg/jfdctflt.c | 168 ++ src/gdcmjpeg/jfdctfst.c | 224 +++ src/gdcmjpeg/jfdctint.c | 283 +++ src/gdcmjpeg/jidctflt.c | 242 +++ src/gdcmjpeg/jidctfst.c | 368 ++++ src/gdcmjpeg/jidctint.c | 389 ++++ src/gdcmjpeg/jidctred.c | 398 ++++ src/gdcmjpeg/jinclude.h | 91 + src/gdcmjpeg/jlossls.h | 151 ++ src/gdcmjpeg/jlossy.h | 120 ++ src/gdcmjpeg/jmemmgr.c | 1174 ++++++++++++ src/gdcmjpeg/jmemnobs.c | 117 ++ src/gdcmjpeg/jmemsys.h | 198 ++ src/gdcmjpeg/jmorecfg.h.in | 435 +++++ src/gdcmjpeg/jpegint.h | 365 ++++ src/gdcmjpeg/jpeglib.h | 1131 +++++++++++ src/gdcmjpeg/jquant1.c | 860 +++++++++ src/gdcmjpeg/jquant2.c | 1312 +++++++++++++ src/gdcmjpeg/jutils.c | 179 ++ src/gdcmjpeg/jversion.h | 14 + src/gdcmjpeg/libjpeg.doc | 3011 ++++++++++++++++++++++++++++++ src/gdcmjpeg/mangle_jpeg12bits.h | 141 ++ src/gdcmjpeg/mangle_jpeg16bits.h | 141 ++ src/gdcmjpeg/mangle_jpeg8bits.h | 139 ++ src/gdcmjpeg/structure.doc | 1042 +++++++++++ src/jdatasrc.cxx | 2 + 99 files changed, 34532 insertions(+), 30 deletions(-) create mode 100644 src/gdcmjpeg/12/CMakeLists.txt create mode 100644 src/gdcmjpeg/16/CMakeLists.txt create mode 100644 src/gdcmjpeg/8/CMakeLists.txt create mode 100644 src/gdcmjpeg/CMakeLists.txt create mode 100644 src/gdcmjpeg/COPYRIGHT.dcmtk create mode 100644 src/gdcmjpeg/README create mode 100644 src/gdcmjpeg/README.GDCM.txt create mode 100644 src/gdcmjpeg/change.log create mode 100644 src/gdcmjpeg/filelist.doc create mode 100644 src/gdcmjpeg/install.doc create mode 100644 src/gdcmjpeg/jaricom.c create mode 100644 src/gdcmjpeg/jcapimin.c create mode 100644 src/gdcmjpeg/jcapistd.c create mode 100644 src/gdcmjpeg/jcarith.c create mode 100644 src/gdcmjpeg/jccoefct.c create mode 100644 src/gdcmjpeg/jccolor.c create mode 100644 src/gdcmjpeg/jcdctmgr.c create mode 100644 src/gdcmjpeg/jcdiffct.c create mode 100644 src/gdcmjpeg/jchuff.c create mode 100644 src/gdcmjpeg/jchuff.h create mode 100644 src/gdcmjpeg/jcinit.c create mode 100644 src/gdcmjpeg/jclhuff.c create mode 100644 src/gdcmjpeg/jclossls.c create mode 100644 src/gdcmjpeg/jclossy.c create mode 100644 src/gdcmjpeg/jcmainct.c create mode 100644 src/gdcmjpeg/jcmarker.c create mode 100644 src/gdcmjpeg/jcmaster.c create mode 100644 src/gdcmjpeg/jcodec.c create mode 100644 src/gdcmjpeg/jcomapi.c create mode 100644 src/gdcmjpeg/jconfig.doc create mode 100644 src/gdcmjpeg/jconfig.h.in create mode 100644 src/gdcmjpeg/jcparam.c create mode 100644 src/gdcmjpeg/jcphuff.c create mode 100644 src/gdcmjpeg/jcpred.c create mode 100644 src/gdcmjpeg/jcprepct.c create mode 100644 src/gdcmjpeg/jcsample.c create mode 100644 src/gdcmjpeg/jcscale.c create mode 100644 src/gdcmjpeg/jcshuff.c create mode 100644 src/gdcmjpeg/jctrans.c create mode 100644 src/gdcmjpeg/jdapimin.c create mode 100644 src/gdcmjpeg/jdapistd.c create mode 100644 src/gdcmjpeg/jdarith.c create mode 100644 src/gdcmjpeg/jdatadst.c create mode 100644 src/gdcmjpeg/jdatasrc.c create mode 100644 src/gdcmjpeg/jdcoefct.c create mode 100644 src/gdcmjpeg/jdcolor.c create mode 100644 src/gdcmjpeg/jdct.h create mode 100644 src/gdcmjpeg/jddctmgr.c create mode 100644 src/gdcmjpeg/jddiffct.c create mode 100644 src/gdcmjpeg/jdhuff.c create mode 100644 src/gdcmjpeg/jdhuff.h create mode 100644 src/gdcmjpeg/jdinput.c create mode 100644 src/gdcmjpeg/jdlhuff.c create mode 100644 src/gdcmjpeg/jdlossls.c create mode 100644 src/gdcmjpeg/jdlossy.c create mode 100644 src/gdcmjpeg/jdmainct.c create mode 100644 src/gdcmjpeg/jdmarker.c create mode 100644 src/gdcmjpeg/jdmaster.c create mode 100644 src/gdcmjpeg/jdmerge.c create mode 100644 src/gdcmjpeg/jdphuff.c create mode 100644 src/gdcmjpeg/jdpostct.c create mode 100644 src/gdcmjpeg/jdpred.c create mode 100644 src/gdcmjpeg/jdsample.c create mode 100644 src/gdcmjpeg/jdscale.c create mode 100644 src/gdcmjpeg/jdshuff.c create mode 100644 src/gdcmjpeg/jdtrans.c create mode 100644 src/gdcmjpeg/jerror.c create mode 100644 src/gdcmjpeg/jerror.h create mode 100644 src/gdcmjpeg/jfdctflt.c create mode 100644 src/gdcmjpeg/jfdctfst.c create mode 100644 src/gdcmjpeg/jfdctint.c create mode 100644 src/gdcmjpeg/jidctflt.c create mode 100644 src/gdcmjpeg/jidctfst.c create mode 100644 src/gdcmjpeg/jidctint.c create mode 100644 src/gdcmjpeg/jidctred.c create mode 100644 src/gdcmjpeg/jinclude.h create mode 100644 src/gdcmjpeg/jlossls.h create mode 100644 src/gdcmjpeg/jlossy.h create mode 100644 src/gdcmjpeg/jmemmgr.c create mode 100644 src/gdcmjpeg/jmemnobs.c create mode 100644 src/gdcmjpeg/jmemsys.h create mode 100644 src/gdcmjpeg/jmorecfg.h.in create mode 100644 src/gdcmjpeg/jpegint.h create mode 100644 src/gdcmjpeg/jpeglib.h create mode 100644 src/gdcmjpeg/jquant1.c create mode 100644 src/gdcmjpeg/jquant2.c create mode 100644 src/gdcmjpeg/jutils.c create mode 100644 src/gdcmjpeg/jversion.h create mode 100644 src/gdcmjpeg/libjpeg.doc create mode 100644 src/gdcmjpeg/mangle_jpeg12bits.h create mode 100644 src/gdcmjpeg/mangle_jpeg16bits.h create mode 100644 src/gdcmjpeg/mangle_jpeg8bits.h create mode 100644 src/gdcmjpeg/structure.doc diff --git a/gdcmPython/gdcm.i b/gdcmPython/gdcm.i index f56077fb..169eff54 100644 --- a/gdcmPython/gdcm.i +++ b/gdcmPython/gdcm.i @@ -291,8 +291,7 @@ typedef unsigned int guint32; // { // $1 = new std::string( PyString_AsString( $input ) ); // } -// -add a note on the rename that works ! +// add a note on the rename that works ! // void Junk(); // void Junk(std::string const & bozo); // diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt index 5cfd632f..5be4a21a 100644 --- a/src/CMakeLists.txt +++ b/src/CMakeLists.txt @@ -1,11 +1,12 @@ #----------------------------------------------------------------------------- # Build jpeg lib first: -SUBDIRS(jpeg) +SUBDIRS(gdcmjpeg) # "jpeglib.h" is defined here: INCLUDE_DIRECTORIES( ${GDCM_SOURCE_DIR}/src ${GDCM_BINARY_DIR}/ #for gdcmConfigure.h + ${GDCM_BINARY_DIR}/src #for gdcmjpeg 8, 12 and 16 ) SET(libgdcm_la_SOURCES @@ -53,15 +54,15 @@ SET(libgdcm_la_SOURCES ADD_LIBRARY(gdcm ${libgdcm_la_SOURCES} ) IF(UNIX) TARGET_LINK_LIBRARIES(gdcm - gdcmijpeg8 - gdcmijpeg12 - gdcmijpeg16 + gdcmjpeg8 + gdcmjpeg12 + gdcmjpeg16 ) ELSE(UNIX) TARGET_LINK_LIBRARIES(gdcm - gdcmijpeg8 - gdcmijpeg12 - gdcmijpeg16 + gdcmjpeg8 + gdcmjpeg12 + gdcmjpeg16 Wsock32.lib #doesn't exist on cygwin ) ENDIF(UNIX) diff --git a/src/gdcmJpeg12.cxx b/src/gdcmJpeg12.cxx index 7cb84bf2..c43f1fcc 100644 --- a/src/gdcmJpeg12.cxx +++ b/src/gdcmJpeg12.cxx @@ -3,8 +3,8 @@ Program: gdcm Module: $RCSfile: gdcmJpeg12.cxx,v $ Language: C++ - Date: $Date: 2004/10/22 03:05:42 $ - Version: $Revision: 1.23 $ + Date: $Date: 2004/11/07 14:28:55 $ + Version: $Revision: 1.24 $ Copyright (c) CREATIS (Centre de Recherche et d'Applications en Traitement de l'Image). All rights reserved. See Doc/License.txt or @@ -18,13 +18,10 @@ #include "gdcmFile.h" extern "C" { -#include "src/jpeg/libijg12/jconfig.h" -#include "src/jpeg/libijg12/jpeglib.h" -#include "src/jpeg/libijg12/jinclude.h" -#include "src/jpeg/libijg12/jerror.h" +#include "gdcmjpeg/12/jinclude.h" +#include "gdcmjpeg/12/jpeglib.h" } - #define gdcm_write_JPEG_file gdcm_write_JPEG_file12 #define gdcm_read_JPEG_file gdcm_read_JPEG_file12 diff --git a/src/gdcmJpeg16.cxx b/src/gdcmJpeg16.cxx index cff5c6d7..fa9368dd 100644 --- a/src/gdcmJpeg16.cxx +++ b/src/gdcmJpeg16.cxx @@ -3,8 +3,8 @@ Program: gdcm Module: $RCSfile: gdcmJpeg16.cxx,v $ Language: C++ - Date: $Date: 2004/10/22 03:05:42 $ - Version: $Revision: 1.2 $ + Date: $Date: 2004/11/07 14:28:55 $ + Version: $Revision: 1.3 $ Copyright (c) CREATIS (Centre de Recherche et d'Applications en Traitement de l'Image). All rights reserved. See Doc/License.txt or @@ -15,17 +15,13 @@ PURPOSE. See the above copyright notices for more information. =========================================================================*/ - #include "gdcmFile.h" extern "C" { -#include "src/jpeg/libijg16/jconfig.h" -#include "src/jpeg/libijg16/jpeglib.h" -#include "src/jpeg/libijg16/jinclude.h" -#include "src/jpeg/libijg16/jerror.h" +#include "gdcmjpeg/16/jinclude.h" +#include "gdcmjpeg/16/jpeglib.h" } - #define gdcm_write_JPEG_file gdcm_write_JPEG_file16 #define gdcm_read_JPEG_file gdcm_read_JPEG_file16 diff --git a/src/gdcmJpeg8.cxx b/src/gdcmJpeg8.cxx index b747f492..f0402549 100644 --- a/src/gdcmJpeg8.cxx +++ b/src/gdcmJpeg8.cxx @@ -3,8 +3,8 @@ Program: gdcm Module: $RCSfile: gdcmJpeg8.cxx,v $ Language: C++ - Date: $Date: 2004/10/22 03:05:42 $ - Version: $Revision: 1.9 $ + Date: $Date: 2004/11/07 14:28:55 $ + Version: $Revision: 1.10 $ Copyright (c) CREATIS (Centre de Recherche et d'Applications en Traitement de l'Image). All rights reserved. See Doc/License.txt or @@ -18,10 +18,8 @@ #include "gdcmFile.h" extern "C" { -#include "src/jpeg/libijg8/jconfig.h" -#include "src/jpeg/libijg8/jpeglib.h" -#include "src/jpeg/libijg8/jinclude.h" -#include "src/jpeg/libijg8/jerror.h" +#include "gdcmjpeg/8/jconfig.h" +#include "gdcmjpeg/8/jpeglib.h" } #define gdcm_write_JPEG_file gdcm_write_JPEG_file8 diff --git a/src/gdcmjpeg/12/CMakeLists.txt b/src/gdcmjpeg/12/CMakeLists.txt new file mode 100644 index 00000000..1cd516df --- /dev/null +++ b/src/gdcmjpeg/12/CMakeLists.txt @@ -0,0 +1,9 @@ +# JPEG 12 bits project + +INCLUDE_DIRECTORIES( + "${CMAKE_CURRENT_BINARY_DIR}" + "${GDCMJPEG_SOURCE_DIR}") +ADD_LIBRARY(gdcmjpeg12 ${JPEG_SOURCES}) +INSTALL_TARGETS(/lib/ gdcmjpeg12) + + diff --git a/src/gdcmjpeg/16/CMakeLists.txt b/src/gdcmjpeg/16/CMakeLists.txt new file mode 100644 index 00000000..70a45c42 --- /dev/null +++ b/src/gdcmjpeg/16/CMakeLists.txt @@ -0,0 +1,9 @@ +# JPEG 16 bits project + +INCLUDE_DIRECTORIES( + "${CMAKE_CURRENT_BINARY_DIR}" + "${GDCMJPEG_SOURCE_DIR}") +ADD_LIBRARY(gdcmjpeg16 ${JPEG_SOURCES}) +INSTALL_TARGETS(/lib/ gdcmjpeg16) + + diff --git a/src/gdcmjpeg/8/CMakeLists.txt b/src/gdcmjpeg/8/CMakeLists.txt new file mode 100644 index 00000000..fc99aa5a --- /dev/null +++ b/src/gdcmjpeg/8/CMakeLists.txt @@ -0,0 +1,8 @@ +# JPEG 8 bits project + +INCLUDE_DIRECTORIES( + "${CMAKE_CURRENT_BINARY_DIR}" + "${GDCMJPEG_SOURCE_DIR}") +ADD_LIBRARY(gdcmjpeg8 ${JPEG_SOURCES}) +INSTALL_TARGETS(/lib/ gdcmjpeg8) + diff --git a/src/gdcmjpeg/CMakeLists.txt b/src/gdcmjpeg/CMakeLists.txt new file mode 100644 index 00000000..7a905f3b --- /dev/null +++ b/src/gdcmjpeg/CMakeLists.txt @@ -0,0 +1,119 @@ +PROJECT(GDCMJPEG) + +INCLUDE_REGULAR_EXPRESSION("^(jchuff|jconfig|jdct|jdhuff|jerror|jinclude|jmemsys|jmorecfg|jpegint|jpeglib|jversion|jpeg).*$") + +# memmgr back ends: compile only one of these into a working library +# (For now, let's use the mode that requires the image fit into memory. +# This is the recommended mode for Win32 anyway.) +SET(systemdependent_SRCS jmemnobs.c) + +# library object files common to compression and decompression +SET(common_SRCS +jcomapi.c jutils.c jerror.c jmemmgr.c +) + +# compression library object files +SET(compression_SRCS +jcapimin.c jcapistd.c jctrans.c jcparam.c jcinit.c +jcmaster.c jcmarker.c jcmainct.c jcprepct.c jccoefct.c jccolor.c +jcsample.c jchuff.c jcphuff.c jcdctmgr.c jfdctfst.c jfdctflt.c +jdatadst.c +) + +# Lossy (DCT) codec: +SET(comp_lossy_SRCS +jfdctint.c +jclossy.c + +# lossless +jclossls.c + +jdarith.c +jcodec.c +jcscale.c +jcshuff.c +jclhuff.c +jcpred.c +jcdiffct.c +) + +# decompression library object files +SET(decompression_SRCS +jdapimin.c jdapistd.c jdtrans.c jdmaster.c +jdinput.c jdmarker.c jdhuff.c jdphuff.c jdmainct.c jdcoefct.c +jdpostct.c jddctmgr.c jidctfst.c jidctflt.c jidctint.c jidctred.c +jdsample.c jdcolor.c jquant1.c jquant2.c jdmerge.c +jdatasrc.c +) + +SET(decomp_lossy_SRCS + jdlossls.c jdlossy.c +jcarith.c +jdlhuff.c +jddiffct.c +jdpred.c +jdscale.c +jdshuff.c +) + +SET(JPEG_HEADER_FILES + jchuff.h + jdct.h + jdhuff.h + jerror.h + jinclude.h + jmemsys.h +# jmorecfg.h #this one need to be configured + jpegint.h + jpeglib.h + jversion.h + jlossy.h + jlossls.h + ) + +SET(JPEG_SOURCES) +FOREACH(src + ${systemdependent_SRCS} + ${common_SRCS} + ${compression_SRCS} + ${decompression_SRCS} + ${comp_lossy_SRCS} + ${decomp_lossy_SRCS} + ) + SET(JPEG_SOURCES ${JPEG_SOURCES} + "${GDCMJPEG_SOURCE_DIR}/${src}") +ENDFOREACH(src) + +IF (WIN32) + IF (BUILD_SHARED_LIBS) + ADD_DEFINITIONS(-DJPEGDLL) + ELSE (BUILD_SHARED_LIBS) + ADD_DEFINITIONS(-DJPEGSTATIC) + ENDIF (BUILD_SHARED_LIBS) +ENDIF (WIN32) + +CONFIGURE_FILE(${GDCMJPEG_SOURCE_DIR}/.NoDartCoverage + ${GDCMJPEG_BINARY_DIR}/.NoDartCoverage) + +# Generate three libraries: jpeg 8bits, 12bits and 16bits +# using only one source directory + +# Particular case jmorecfg.h needs to be specified either 8, 12 or 16 bits: +FOREACH(bits 8 12 16) + SET(CMAKE_BITS_IN_JSAMPLE ${bits}) + CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/jmorecfg.h.in + ${CMAKE_CURRENT_BINARY_DIR}/${bits}/jmorecfg.h @ONLY IMMEDIATE) + SET(BITS_TYPE_JPEG_MANGLE_NAME "gdcmjpeg/mangle_jpeg${bits}bits.h") + CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/jconfig.h.in + ${CMAKE_CURRENT_BINARY_DIR}/${bits}/jconfig.h @ONLY IMMEDIATE) + # Dummy copy for GDCM to include with no conflict + CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/jpeglib.h + ${CMAKE_CURRENT_BINARY_DIR}/${bits}/jpeglib.h COPYONLY IMMEDIATE) + CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/jerror.h + ${CMAKE_CURRENT_BINARY_DIR}/${bits}/jerror.h COPYONLY IMMEDIATE) + CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/jinclude.h + ${CMAKE_CURRENT_BINARY_DIR}/${bits}/jinclude.h COPYONLY IMMEDIATE) +ENDFOREACH(bits) + +SUBDIRS(8 12 16) + diff --git a/src/gdcmjpeg/COPYRIGHT.dcmtk b/src/gdcmjpeg/COPYRIGHT.dcmtk new file mode 100644 index 00000000..4c0359f2 --- /dev/null +++ b/src/gdcmjpeg/COPYRIGHT.dcmtk @@ -0,0 +1,258 @@ + +COPYRIGHT + +Unless otherwise specified, the DCMTK software package has the +following copyright: + +/* + * Copyright (C) 1994-2004, OFFIS + * + * This software and supporting documentation were developed by + * + * Kuratorium OFFIS e.V. + * Healthcare Information and Communication Systems + * Escherweg 2 + * D-26121 Oldenburg, Germany + * + * THIS SOFTWARE IS MADE AVAILABLE, AS IS, AND OFFIS MAKES NO WARRANTY + * REGARDING THE SOFTWARE, ITS PERFORMANCE, ITS MERCHANTABILITY OR + * FITNESS FOR ANY PARTICULAR USE, FREEDOM FROM ANY COMPUTER DISEASES OR + * ITS CONFORMITY TO ANY SPECIFICATION. THE ENTIRE RISK AS TO QUALITY AND + * PERFORMANCE OF THE SOFTWARE IS WITH THE USER. + * + * Copyright of the software and supporting documentation is, unless + * otherwise stated, owned by OFFIS, and free access is hereby granted as + * a license to use this software, copy this software and prepare + * derivative works based upon this software. However, any distribution + * of this software source code or supporting documentation or derivative + * works (source code and supporting documentation) must include the + * three paragraphs of this copyright notice. + * + */ + +Some portions of the DCMTK software package are derived from earlier +versions of this software with the following copyright, and can be +identifed by the following copyright notice located in each source file: + +/* + * Copyright (C) 1993/1994, OFFIS, Oldenburg University and CERIUM + * + * This software and supporting documentation were + * developed by + * + * Institut OFFIS + * Bereich Kommunikationssysteme + * Westerstr. 10-12 + * 26121 Oldenburg, Germany + * + * Fachbereich Informatik + * Abteilung Prozessinformatik + * Carl von Ossietzky Universitaet Oldenburg + * Ammerlaender Heerstr. 114-118 + * 26111 Oldenburg, Germany + * + * CERIUM + * Laboratoire SIM + * Faculte de Medecine + * 2 Avenue du Pr. Leon Bernard + * 35043 Rennes Cedex, France + * + * for CEN/TC251/WG4 as a contribution to the Radiological + * Society of North America (RSNA) 1993 Digital Imaging and + * Communications in Medicine (DICOM) Demonstration. + * + * THIS SOFTWARE IS MADE AVAILABLE, AS IS, AND NEITHER OFFIS, + * OLDENBURG UNIVERSITY NOR CERIUM MAKE ANY WARRANTY REGARDING + * THE SOFTWARE, ITS PERFORMANCE, ITS MERCHANTABILITY OR + * FITNESS FOR ANY PARTICULAR USE, FREEDOM FROM ANY COMPUTER + * DISEASES OR ITS CONFORMITY TO ANY SPECIFICATION. THE + * ENTIRE RISK AS TO QUALITY AND PERFORMANCE OF THE SOFTWARE + * IS WITH THE USER. + * + * Copyright of the software and supporting documentation + * is, unless otherwise stated, jointly owned by OFFIS, + * Oldenburg University and CERIUM and free access is hereby + * granted as a license to use this software, copy this + * software and prepare derivative works based upon this + * software. However, any distribution of this software + * source code or supporting documentation or derivative + * works (source code and supporting documentation) must + * include the three paragraphs of this copyright notice. + * + */ + +Some other parts of this software within the dcmtk/dcmnet +sub-package related to the DICOM Upper Layer Protocol are +derived from software developed for the RSNA'93 DICOM +demonstration and kindly made available to us by the Mallinckrodt +Institute of Radiology. Such software can be identifed by the +following copyright notice located in each affected source file: + +/* + * Copyright (C) 1993, RSNA and Washington University + * + * The software and supporting documentation for the Radiological + * Society of North America (RSNA) 1993 Digital Imaging and + * Communications in Medicine (DICOM) Demonstration were developed + * at the + * Electronic Radiology Laboratory + * Mallinckrodt Institute of Radiology + * Washington University School of Medicine + * 510 S. Kingshighway Blvd. + * St. Louis, MO 63110 + * as part of the 1993 DICOM Central Test Node project for, and + * under contract with, the Radiological Society of North America. + * + * THIS SOFTWARE IS MADE AVAILABLE, AS IS, AND NEITHER RSNA NOR + * WASHINGTON UNIVERSITY MAKE ANY WARRANTY ABOUT THE SOFTWARE, ITS + * PERFORMANCE, ITS MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR + * USE, FREEDOM FROM ANY COMPUTER DISEASES OR ITS CONFORMITY TO ANY + * SPECIFICATION. THE ENTIRE RISK AS TO QUALITY AND PERFORMANCE OF + * THE SOFTWARE IS WITH THE USER. + * + * Copyright of the software and supporting documentation is + * jointly owned by RSNA and Washington University, and free access + * is hereby granted as a license to use this software, copy this + * software and prepare derivative works based upon this software. + * However, any distribution of this software source code or + * supporting documentation or derivative works (source code and + * supporting documentation) must include the three paragraphs of + * the copyright notice. + */ + +The dcmjpeg sub-package includes an adapted version of the Independent JPEG +Group Toolkit Version 6b, which is contained in dcmjpeg/libijg8, +dcmjpeg/libijg12 and dcmjpeg/libijg16. This toolkit is covered by the +following copyright. The original README file for the Independent JPEG +Group Toolkit is located in dcmjpeg/docs/ijg_readme.txt. + +/* + * The authors make NO WARRANTY or representation, either express or implied, + * with respect to this software, its quality, accuracy, merchantability, or + * fitness for a particular purpose. This software is provided "AS IS", and you, + * its user, assume the entire risk as to its quality and accuracy. + * + * This software is copyright (C) 1991-1998, Thomas G. Lane. + * All Rights Reserved except as specified below. + * + * Permission is hereby granted to use, copy, modify, and distribute this + * software (or portions thereof) for any purpose, without fee, subject to these + * conditions: + * (1) If any part of the source code for this software is distributed, then this + * README file must be included, with this copyright and no-warranty notice + * unaltered; and any additions, deletions, or changes to the original files + * must be clearly indicated in accompanying documentation. + * (2) If only executable code is distributed, then the accompanying + * documentation must state that "this software is based in part on the work of + * the Independent JPEG Group". + * (3) Permission for use of this software is granted only if the user accepts + * full responsibility for any undesirable consequences; the authors accept + * NO LIABILITY for damages of any kind. + * + * These conditions apply to any software derived from or based on the IJG code, + * not just to the unmodified library. If you use our work, you ought to + * acknowledge us. + * + * Permission is NOT granted for the use of any IJG author's name or company name + * in advertising or publicity relating to this software or products derived from + * it. This software may be referred to only as "the Independent JPEG Group's + * software". + * + * We specifically permit and encourage the use of this software as the basis of + * commercial products, provided that all warranty or liability claims are + * assumed by the product vendor. + */ + + +The color quantization code in module dcmimage (dcmquant and the related +classes) is derived from code written by Jef Poskanzer for the NetPBM +toolkit which has the following copyright: + +/* + * Copyright (C) 1989, 1991 by Jef Poskanzer. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose and without fee is hereby granted, provided + * that the above copyright notice appear in all copies and that both that + * copyright notice and this permission notice appear in supporting + * documentation. This software is provided "as is" without express or + * implied warranty. + */ + + +The code for the OFStandard::strlcpy and OFStandard::strlcat helper +functions in ofstd/libsrc/ofstd.cc has been derived from the BSD +implementation of strlcpy() and strlcat() and which carries the +following copyright notice: + +/* + * Copyright (c) 1998 Todd C. Miller + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL + * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + + +The code for the OFStandard::atof helper function in +ofstd/libsrc/ofstd.cc has been derived from an implementation which +carries the following copyright notice: + +/* + * Copyright 1988 Regents of the University of California + * Permission to use, copy, modify, and distribute this software and + * its documentation for any purpose and without fee is hereby granted, + * provided that the above copyright notice appear in all copies. The + * University of California makes no representations about the + * suitability of this software for any purpose. It is provided "as + * is" without express or implied warranty. + * + * + * The code for OFStandard::ftoa has been derived + * from an implementation which carries the following copyright notice: + * + * Copyright (c) 1988 Regents of the University of California. + * All rights reserved. + * + * Redistribution and use in source and binary forms are permitted + * provided that the above copyright notice and this paragraph are + * duplicated in all such forms and that any documentation, + * advertising materials, and other materials related to such + * distribution and use acknowledge that the software was developed + * by the University of California, Berkeley. The name of the + * University may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +The "Base64" encoder/decoder in ofstd/libsrc/ofstd.cc has been derived +from an implementation which carries the following copyright notice: + +/* + * Copyright (c) 1999, Bob Withers - bwit(at)pobox.com + * + * This code may be freely used for any purpose, either personal or commercial, + * provided the authors copyright notice remains intact. + */ + diff --git a/src/gdcmjpeg/README b/src/gdcmjpeg/README new file mode 100644 index 00000000..24235947 --- /dev/null +++ b/src/gdcmjpeg/README @@ -0,0 +1,385 @@ +The Independent JPEG Group's JPEG software +========================================== + +README for release 6b of 27-Mar-1998 +==================================== + +This distribution contains the sixth public release of the Independent JPEG +Group's free JPEG software. You are welcome to redistribute this software and +to use it for any purpose, subject to the conditions under LEGAL ISSUES, below. + +Serious users of this software (particularly those incorporating it into +larger programs) should contact IJG at jpeg-info@uunet.uu.net to be added to +our electronic mailing list. Mailing list members are notified of updates +and have a chance to participate in technical discussions, etc. + +This software is the work of Tom Lane, Philip Gladstone, Jim Boucher, +Lee Crocker, Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi, +Guido Vollbeding, Ge' Weijers, and other members of the Independent JPEG +Group. + +IJG is not affiliated with the official ISO JPEG standards committee. + + +DOCUMENTATION ROADMAP +===================== + +This file contains the following sections: + +OVERVIEW General description of JPEG and the IJG software. +LEGAL ISSUES Copyright, lack of warranty, terms of distribution. +REFERENCES Where to learn more about JPEG. +ARCHIVE LOCATIONS Where to find newer versions of this software. +RELATED SOFTWARE Other stuff you should get. +FILE FORMAT WARS Software *not* to get. +TO DO Plans for future IJG releases. + +Other documentation files in the distribution are: + +User documentation: + install.doc How to configure and install the IJG software. + usage.doc Usage instructions for cjpeg, djpeg, jpegtran, + rdjpgcom, and wrjpgcom. + *.1 Unix-style man pages for programs (same info as usage.doc). + wizard.doc Advanced usage instructions for JPEG wizards only. + change.log Version-to-version change highlights. +Programmer and internal documentation: + libjpeg.doc How to use the JPEG library in your own programs. + example.c Sample code for calling the JPEG library. + structure.doc Overview of the JPEG library's internal structure. + filelist.doc Road map of IJG files. + coderules.doc Coding style rules --- please read if you contribute code. + +Please read at least the files install.doc and usage.doc. Useful information +can also be found in the JPEG FAQ (Frequently Asked Questions) article. See +ARCHIVE LOCATIONS below to find out where to obtain the FAQ article. + +If you want to understand how the JPEG code works, we suggest reading one or +more of the REFERENCES, then looking at the documentation files (in roughly +the order listed) before diving into the code. + + +OVERVIEW +======== + +This package contains C software to implement JPEG image compression and +decompression. JPEG (pronounced "jay-peg") is a standardized compression +method for full-color and gray-scale images. JPEG is intended for compressing +"real-world" scenes; line drawings, cartoons and other non-realistic images +are not its strong suit. JPEG is lossy, meaning that the output image is not +exactly identical to the input image. Hence you must not use JPEG if you +have to have identical output bits. However, on typical photographic images, +very good compression levels can be obtained with no visible change, and +remarkably high compression levels are possible if you can tolerate a +low-quality image. For more details, see the references, or just experiment +with various compression settings. + +This software implements JPEG baseline, extended-sequential, progressive +and lossless compression processes. Provision is made for supporting all +variants of these processes, although some uncommon parameter settings aren't +implemented yet. For legal reasons, we are not distributing code for the +arithmetic-coding variants of JPEG; see LEGAL ISSUES. We have made no +provision for supporting the hierarchical processes defined in the standard. + +We provide a set of library routines for reading and writing JPEG image files, +plus two sample applications "cjpeg" and "djpeg", which use the library to +perform conversion between JPEG and some other popular image file formats. +The library is intended to be reused in other applications. + +In order to support file conversion and viewing software, we have included +considerable functionality beyond the bare JPEG coding/decoding capability; +for example, the color quantization modules are not strictly part of JPEG +decoding, but they are essential for output to colormapped file formats or +colormapped displays. These extra functions can be compiled out of the +library if not required for a particular application. We have also included +"jpegtran", a utility for lossless transcoding between different JPEG +processes, and "rdjpgcom" and "wrjpgcom", two simple applications for +inserting and extracting textual comments in JFIF files. + +The emphasis in designing this software has been on achieving portability and +flexibility, while also making it fast enough to be useful. In particular, +the software is not intended to be read as a tutorial on JPEG. (See the +REFERENCES section for introductory material.) Rather, it is intended to +be reliable, portable, industrial-strength code. We do not claim to have +achieved that goal in every aspect of the software, but we strive for it. + +We welcome the use of this software as a component of commercial products. +No royalty is required, but we do ask for an acknowledgement in product +documentation, as described under LEGAL ISSUES. + + +LEGAL ISSUES +============ + +In plain English: + +1. We don't promise that this software works. (But if you find any bugs, + please let us know!) +2. You can use this software for whatever you want. You don't have to pay us. +3. You may not pretend that you wrote this software. If you use it in a + program, you must acknowledge somewhere in your documentation that + you've used the IJG code. + +In legalese: + +The authors make NO WARRANTY or representation, either express or implied, +with respect to this software, its quality, accuracy, merchantability, or +fitness for a particular purpose. This software is provided "AS IS", and you, +its user, assume the entire risk as to its quality and accuracy. + +This software is copyright (C) 1991-1998, Thomas G. Lane. +All Rights Reserved except as specified below. + +Permission is hereby granted to use, copy, modify, and distribute this +software (or portions thereof) for any purpose, without fee, subject to these +conditions: +(1) If any part of the source code for this software is distributed, then this +README file must be included, with this copyright and no-warranty notice +unaltered; and any additions, deletions, or changes to the original files +must be clearly indicated in accompanying documentation. +(2) If only executable code is distributed, then the accompanying +documentation must state that "this software is based in part on the work of +the Independent JPEG Group". +(3) Permission for use of this software is granted only if the user accepts +full responsibility for any undesirable consequences; the authors accept +NO LIABILITY for damages of any kind. + +These conditions apply to any software derived from or based on the IJG code, +not just to the unmodified library. If you use our work, you ought to +acknowledge us. + +Permission is NOT granted for the use of any IJG author's name or company name +in advertising or publicity relating to this software or products derived from +it. This software may be referred to only as "the Independent JPEG Group's +software". + +We specifically permit and encourage the use of this software as the basis of +commercial products, provided that all warranty or liability claims are +assumed by the product vendor. + + +ansi2knr.c is included in this distribution by permission of L. Peter Deutsch, +sole proprietor of its copyright holder, Aladdin Enterprises of Menlo Park, CA. +ansi2knr.c is NOT covered by the above copyright and conditions, but instead +by the usual distribution terms of the Free Software Foundation; principally, +that you must include source code if you redistribute it. (See the file +ansi2knr.c for full details.) However, since ansi2knr.c is not needed as part +of any program generated from the IJG code, this does not limit you more than +the foregoing paragraphs do. + +The Unix configuration script "configure" was produced with GNU Autoconf. +It is copyright by the Free Software Foundation but is freely distributable. +The same holds for its supporting scripts (config.guess, config.sub, +ltconfig, ltmain.sh). Another support script, install-sh, is copyright +by M.I.T. but is also freely distributable. + +It appears that the arithmetic coding option of the JPEG spec is covered by +patents owned by IBM, AT&T, and Mitsubishi. Hence arithmetic coding cannot +legally be used without obtaining one or more licenses. For this reason, +support for arithmetic coding has been removed from the free JPEG software. +(Since arithmetic coding provides only a marginal gain over the unpatented +Huffman mode, it is unlikely that very many implementations will support it.) +So far as we are aware, there are no patent restrictions on the remaining +code. + +The IJG distribution formerly included code to read and write GIF files. +To avoid entanglement with the Unisys LZW patent, GIF reading support has +been removed altogether, and the GIF writer has been simplified to produce +"uncompressed GIFs". This technique does not use the LZW algorithm; the +resulting GIF files are larger than usual, but are readable by all standard +GIF decoders. + +We are required to state that + "The Graphics Interchange Format(c) is the Copyright property of + CompuServe Incorporated. GIF(sm) is a Service Mark property of + CompuServe Incorporated." + + +REFERENCES +========== + +We highly recommend reading one or more of these references before trying to +understand the innards of the JPEG software. + +The best short technical introduction to the JPEG compression algorithm is + Wallace, Gregory K. "The JPEG Still Picture Compression Standard", + Communications of the ACM, April 1991 (vol. 34 no. 4), pp. 30-44. +(Adjacent articles in that issue discuss MPEG motion picture compression, +applications of JPEG, and related topics.) If you don't have the CACM issue +handy, a PostScript file containing a revised version of Wallace's article is +available at ftp://ftp.uu.net/graphics/jpeg/wallace.ps.gz. The file (actually +a preprint for an article that appeared in IEEE Trans. Consumer Electronics) +omits the sample images that appeared in CACM, but it includes corrections +and some added material. Note: the Wallace article is copyright ACM and IEEE, +and it may not be used for commercial purposes. + +A somewhat less technical, more leisurely introduction to JPEG can be found in +"The Data Compression Book" by Mark Nelson and Jean-loup Gailly, published by +M&T Books (New York), 2nd ed. 1996, ISBN 1-55851-434-1. This book provides +good explanations and example C code for a multitude of compression methods +including JPEG. It is an excellent source if you are comfortable reading C +code but don't know much about data compression in general. The book's JPEG +sample code is far from industrial-strength, but when you are ready to look +at a full implementation, you've got one here... + +The best full description of JPEG is the textbook "JPEG Still Image Data +Compression Standard" by William B. Pennebaker and Joan L. Mitchell, published +by Van Nostrand Reinhold, 1993, ISBN 0-442-01272-1. Price US$59.95, 638 pp. +The book includes the complete text of the ISO JPEG standards (DIS 10918-1 +and draft DIS 10918-2). This is by far the most complete exposition of JPEG +in existence, and we highly recommend it. + +The JPEG standard itself is not available electronically; you must order a +paper copy through ISO or ITU. (Unless you feel a need to own a certified +official copy, we recommend buying the Pennebaker and Mitchell book instead; +it's much cheaper and includes a great deal of useful explanatory material.) +In the USA, copies of the standard may be ordered from ANSI Sales at (212) +642-4900, or from Global Engineering Documents at (800) 854-7179. (ANSI +doesn't take credit card orders, but Global does.) It's not cheap: as of +1992, ANSI was charging $95 for Part 1 and $47 for Part 2, plus 7% +shipping/handling. The standard is divided into two parts, Part 1 being the +actual specification, while Part 2 covers compliance testing methods. Part 1 +is titled "Digital Compression and Coding of Continuous-tone Still Images, +Part 1: Requirements and guidelines" and has document numbers ISO/IEC IS +10918-1, ITU-T T.81. Part 2 is titled "Digital Compression and Coding of +Continuous-tone Still Images, Part 2: Compliance testing" and has document +numbers ISO/IEC IS 10918-2, ITU-T T.83. + +Some extensions to the original JPEG standard are defined in JPEG Part 3, +a newer ISO standard numbered ISO/IEC IS 10918-3 and ITU-T T.84. IJG +currently does not support any Part 3 extensions. + +The JPEG standard does not specify all details of an interchangeable file +format. For the omitted details we follow the "JFIF" conventions, revision +1.02. A copy of the JFIF spec is available from: + Literature Department + C-Cube Microsystems, Inc. + 1778 McCarthy Blvd. + Milpitas, CA 95035 + phone (408) 944-6300, fax (408) 944-6314 +A PostScript version of this document is available by FTP at +ftp://ftp.uu.net/graphics/jpeg/jfif.ps.gz. There is also a plain text +version at ftp://ftp.uu.net/graphics/jpeg/jfif.txt.gz, but it is missing +the figures. + +The TIFF 6.0 file format specification can be obtained by FTP from +ftp://ftp.sgi.com/graphics/tiff/TIFF6.ps.gz. The JPEG incorporation scheme +found in the TIFF 6.0 spec of 3-June-92 has a number of serious problems. +IJG does not recommend use of the TIFF 6.0 design (TIFF Compression tag 6). +Instead, we recommend the JPEG design proposed by TIFF Technical Note #2 +(Compression tag 7). Copies of this Note can be obtained from ftp.sgi.com or +from ftp://ftp.uu.net/graphics/jpeg/. It is expected that the next revision +of the TIFF spec will replace the 6.0 JPEG design with the Note's design. +Although IJG's own code does not support TIFF/JPEG, the free libtiff library +uses our library to implement TIFF/JPEG per the Note. libtiff is available +from ftp://ftp.sgi.com/graphics/tiff/. + + +ARCHIVE LOCATIONS +================= + +The "official" archive site for this software is ftp.uu.net (Internet +address 192.48.96.9). The most recent released version can always be found +there in directory graphics/jpeg. This particular version will be archived +as ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz. If you don't have +direct Internet access, UUNET's archives are also available via UUCP; contact +help@uunet.uu.net for information on retrieving files that way. + +Numerous Internet sites maintain copies of the UUNET files. However, only +ftp.uu.net is guaranteed to have the latest official version. + +You can also obtain this software in DOS-compatible "zip" archive format from +the SimTel archives (ftp://ftp.simtel.net/pub/simtelnet/msdos/graphics/), or +on CompuServe in the Graphics Support forum (GO CIS:GRAPHSUP), library 12 +"JPEG Tools". Again, these versions may sometimes lag behind the ftp.uu.net +release. + +The JPEG FAQ (Frequently Asked Questions) article is a useful source of +general information about JPEG. It is updated constantly and therefore is +not included in this distribution. The FAQ is posted every two weeks to +Usenet newsgroups comp.graphics.misc, news.answers, and other groups. +It is available on the World Wide Web at http://www.faqs.org/faqs/jpeg-faq/ +and other news.answers archive sites, including the official news.answers +archive at rtfm.mit.edu: ftp://rtfm.mit.edu/pub/usenet/news.answers/jpeg-faq/. +If you don't have Web or FTP access, send e-mail to mail-server@rtfm.mit.edu +with body + send usenet/news.answers/jpeg-faq/part1 + send usenet/news.answers/jpeg-faq/part2 + + +RELATED SOFTWARE +================ + +Numerous viewing and image manipulation programs now support JPEG. (Quite a +few of them use this library to do so.) The JPEG FAQ described above lists +some of the more popular free and shareware viewers, and tells where to +obtain them on Internet. + +If you are on a Unix machine, we highly recommend Jef Poskanzer's free +PBMPLUS software, which provides many useful operations on PPM-format image +files. In particular, it can convert PPM images to and from a wide range of +other formats, thus making cjpeg/djpeg considerably more useful. The latest +version is distributed by the NetPBM group, and is available from numerous +sites, notably ftp://wuarchive.wustl.edu/graphics/graphics/packages/NetPBM/. +Unfortunately PBMPLUS/NETPBM is not nearly as portable as the IJG software is; +you are likely to have difficulty making it work on any non-Unix machine. + +A different free JPEG implementation, written by the PVRG group at Stanford, +is available from ftp://havefun.stanford.edu/pub/jpeg/. This program +is designed for research and experimentation rather than production use; +it is slower, harder to use, and less portable than the IJG code, but it +is easier to read and modify. Also, the PVRG code supports lossless JPEG, +which we do not. (On the other hand, it doesn't do progressive JPEG.) + + +FILE FORMAT WARS +================ + +Some JPEG programs produce files that are not compatible with our library. +The root of the problem is that the ISO JPEG committee failed to specify a +concrete file format. Some vendors "filled in the blanks" on their own, +creating proprietary formats that no one else could read. (For example, none +of the early commercial JPEG implementations for the Macintosh were able to +exchange compressed files.) + +The file format we have adopted is called JFIF (see REFERENCES). This format +has been agreed to by a number of major commercial JPEG vendors, and it has +become the de facto standard. JFIF is a minimal or "low end" representation. +We recommend the use of TIFF/JPEG (TIFF revision 6.0 as modified by TIFF +Technical Note #2) for "high end" applications that need to record a lot of +additional data about an image. TIFF/JPEG is fairly new and not yet widely +supported, unfortunately. + +The upcoming JPEG Part 3 standard defines a file format called SPIFF. +SPIFF is interoperable with JFIF, in the sense that most JFIF decoders should +be able to read the most common variant of SPIFF. SPIFF has some technical +advantages over JFIF, but its major claim to fame is simply that it is an +official standard rather than an informal one. At this point it is unclear +whether SPIFF will supersede JFIF or whether JFIF will remain the de-facto +standard. IJG intends to support SPIFF once the standard is frozen, but we +have not decided whether it should become our default output format or not. +(In any case, our decoder will remain capable of reading JFIF indefinitely.) + +Various proprietary file formats incorporating JPEG compression also exist. +We have little or no sympathy for the existence of these formats. Indeed, +one of the original reasons for developing this free software was to help +force convergence on common, open format standards for JPEG files. Don't +use a proprietary file format! + + +TO DO +===== + +The major thrust for v7 will probably be improvement of visual quality. +The current method for scaling the quantization tables is known not to be +very good at low Q values. We also intend to investigate block boundary +smoothing, "poor man's variable quantization", and other means of improving +quality-vs-file-size performance without sacrificing compatibility. + +In future versions, we are considering supporting some of the upcoming JPEG +Part 3 extensions --- principally, variable quantization and the SPIFF file +format. + +As always, speeding things up is of great interest. + +Please send bug reports, offers of help, etc. to jpeg-info@uunet.uu.net. diff --git a/src/gdcmjpeg/README.GDCM.txt b/src/gdcmjpeg/README.GDCM.txt new file mode 100644 index 00000000..e88393ae --- /dev/null +++ b/src/gdcmjpeg/README.GDCM.txt @@ -0,0 +1,105 @@ +This directory contains a subset of the Independent JPEG Group's (IJG) +libjpeg version 6b. We only include enough of distribution to build +libjpeg. We do not include the standard executables that come with +libjpeg (cjpeg, djpeg, etc.). Furthermore, the standard libjpeg build +process is replaced with a CMake build process. + +We'd like to thank the IJG for distributing a public JPEG IO library. + +We'd like to also thank the dcmtk crew for releasing their toolkit under such a nice license that allow us to patch ijg properly to handle all sort of jpeg compression found in the DICOM implementation. The copyright can be found in COPYRIGHT.dcmtk. + +Modifications +------------- + +1. +jconfig.h is usually generated by the build process. For this distribution, +we ship a version of jconfig.h.in to be used across several platforms. It's +purpose is also to allow generation of both 8bits and 12bits lib. + + + +2. +jdhuff.c was modified to support special Philips MRI image: + +Index: jdhuff.c +=================================================================== +RCS file: /cvs/public/gdcm/src/jpeg/libijg8/jdhuff.c,v +retrieving revision 1.1 +diff -u -3 -p -r1.1 jdhuff.c +--- jdhuff.c 24 Jun 2003 10:09:48 -0000 1.1 ++++ jdhuff.c 7 Oct 2004 02:29:43 -0000 +@@ -259,8 +259,11 @@ jpeg_make_d_derived_tbl (j_decompress_pt + if (isDC) { + for (i = 0; i < numsymbols; i++) { + int sym = htbl->huffval[i]; +- if (sym < 0 || sym > 15) +- ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); ++ if (sym < 0 || sym > 15) { ++ // Now, we can read Philips MRI Images ++ htbl->huffval[i]=15; ++// ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); ++ } + } + } + } + + +3. +jmorecfg.h was modified so that we can modify it automatically at build time to +either generate a 8bits jpeg lib or 12bits jpeg library: + +Index: jmorecfg.h +=================================================================== +RCS file: /cvs/public/gdcm/src/jpeg/libijg8/jmorecfg.h,v +retrieving revision 1.4 +diff -u -3 -p -r1.4 jmorecfg.h +--- jmorecfg.h 31 Oct 2003 14:59:50 -0000 1.4 ++++ jmorecfg.h 7 Oct 2004 02:30:40 -0000 +@@ -19,7 +19,8 @@ + * We do not support run-time selection of data precision, sorry. + */ + +-#define BITS_IN_JSAMPLE 8 /* use 8 or 12 */ ++//#define BITS_IN_JSAMPLE 8 /* use 8 or 12 */ ++#define BITS_IN_JSAMPLE @GDCM_BITS_IN_JSAMPLE@ + + /* + * Maximum number of components (color channels) allowed in JPEG image. + + + + +4. +To further allow us to have to different copy of the 8, 12 and 16 bits jpeg +library we had to mangle the name. Fur this purpose two new file were added to +the library: gdcm_mangle_8bits.h, gdcm_mangle_12bits.h and gdcm_mangle_16bits.h. +Those file were generated using: + + nm libgdcmijpeg8.a | grep " [R|T] " | colrm 1 11 | sort + + +5. +In order to read lossless images, we had to apply the ls-patch to jpeg-6b. So I started from scratch: + +tar xvfz /tmp/jpegsrc.v6b.tar.gz (1) +patch < /tmp/ljpeg-6b.patch (2) +patch -p0 < arithmetic-without-arith-option-full.patch (3) +patch -p0 < warnings10-14.patch (4) +patch -p0 < previous-gdcm.patch (5) +----------------------------------------------------------- += The subdir src/jpeg/libijg + +(now I also need to apply the redhat patch for cplusplus lib) + +(1) http://www.ijg.org/files/jpegsrc.v6b.tar.gz +(2) http://www.oceana.com/ftp/ljpeg/ljpeg-patch.v6b.tar.gz +(3), (4) and (5) http://www.creatis.insa-lyon.fr/~malaterre/jpeg/ + +(3) Was made with a carefull inspection of dcmtk code (see convert.sh at the same spot as the patch) +(4) Is basically just compilation of the lib with -W -Wall -Werror +(5) This contains some configuration copy/paste from VTK, and the 'well known' 12 bits Philips MRI DICOM patch + + + +NOTE for later: +(shoud we disable getenv just as dcmtk ? there is a ijg flag for that NO_ENV or something similar diff --git a/src/gdcmjpeg/change.log b/src/gdcmjpeg/change.log new file mode 100644 index 00000000..74102c0d --- /dev/null +++ b/src/gdcmjpeg/change.log @@ -0,0 +1,217 @@ +CHANGE LOG for Independent JPEG Group's JPEG software + + +Version 6b 27-Mar-1998 +----------------------- + +jpegtran has new features for lossless image transformations (rotation +and flipping) as well as "lossless" reduction to grayscale. + +jpegtran now copies comments by default; it has a -copy switch to enable +copying all APPn blocks as well, or to suppress comments. (Formerly it +always suppressed comments and APPn blocks.) jpegtran now also preserves +JFIF version and resolution information. + +New decompressor library feature: COM and APPn markers found in the input +file can be saved in memory for later use by the application. (Before, +you had to code this up yourself with a custom marker processor.) + +There is an unused field "void * client_data" now in compress and decompress +parameter structs; this may be useful in some applications. + +JFIF version number information is now saved by the decoder and accepted by +the encoder. jpegtran uses this to copy the source file's version number, +to ensure "jpegtran -copy all" won't create bogus files that contain JFXX +extensions but claim to be version 1.01. Applications that generate their +own JFXX extension markers also (finally) have a supported way to cause the +encoder to emit JFIF version number 1.02. + +djpeg's trace mode reports JFIF 1.02 thumbnail images as such, rather +than as unknown APP0 markers. + +In -verbose mode, djpeg and rdjpgcom will try to print the contents of +APP12 markers as text. Some digital cameras store useful text information +in APP12 markers. + +Handling of truncated data streams is more robust: blocks beyond the one in +which the error occurs will be output as uniform gray, or left unchanged +if decoding a progressive JPEG. The appearance no longer depends on the +Huffman tables being used. + +Huffman tables are checked for validity much more carefully than before. + +To avoid the Unisys LZW patent, djpeg's GIF output capability has been +changed to produce "uncompressed GIFs", and cjpeg's GIF input capability +has been removed altogether. We're not happy about it either, but there +seems to be no good alternative. + +The configure script now supports building libjpeg as a shared library +on many flavors of Unix (all the ones that GNU libtool knows how to +build shared libraries for). Use "./configure --enable-shared" to +try this out. + +New jconfig file and makefiles for Microsoft Visual C++ and Developer Studio. +Also, a jconfig file and a build script for Metrowerks CodeWarrior +on Apple Macintosh. makefile.dj has been updated for DJGPP v2, and there +are miscellaneous other minor improvements in the makefiles. + +jmemmac.c now knows how to create temporary files following Mac System 7 +conventions. + +djpeg's -map switch is now able to read raw-format PPM files reliably. + +cjpeg -progressive -restart no longer generates any unnecessary DRI markers. + +Multiple calls to jpeg_simple_progression for a single JPEG object +no longer leak memory. + + +Version 6a 7-Feb-96 +-------------------- + +Library initialization sequence modified to detect version mismatches +and struct field packing mismatches between library and calling application. +This change requires applications to be recompiled, but does not require +any application source code change. + +All routine declarations changed to the style "GLOBAL(type) name ...", +that is, GLOBAL, LOCAL, METHODDEF, EXTERN are now macros taking the +routine's return type as an argument. This makes it possible to add +Microsoft-style linkage keywords to all the routines by changing just +these macros. Note that any application code that was using these macros +will have to be changed. + +DCT coefficient quantization tables are now stored in normal array order +rather than zigzag order. Application code that calls jpeg_add_quant_table, +or otherwise manipulates quantization tables directly, will need to be +changed. If you need to make such code work with either older or newer +versions of the library, a test like "#if JPEG_LIB_VERSION >= 61" is +recommended. + +djpeg's trace capability now dumps DQT tables in natural order, not zigzag +order. This allows the trace output to be made into a "-qtables" file +more easily. + +New system-dependent memory manager module for use on Apple Macintosh. + +Fix bug in cjpeg's -smooth option: last one or two scanlines would be +duplicates of the prior line unless the image height mod 16 was 1 or 2. + +Repair minor problems in VMS, BCC, MC6 makefiles. + +New configure script based on latest GNU Autoconf. + +Correct the list of include files needed by MetroWerks C for ccommand(). + +Numerous small documentation updates. + + +Version 6 2-Aug-95 +------------------- + +Progressive JPEG support: library can read and write full progressive JPEG +files. A "buffered image" mode supports incremental decoding for on-the-fly +display of progressive images. Simply recompiling an existing IJG-v5-based +decoder with v6 should allow it to read progressive files, though of course +without any special progressive display. + +New "jpegtran" application performs lossless transcoding between different +JPEG formats; primarily, it can be used to convert baseline to progressive +JPEG and vice versa. In support of jpegtran, the library now allows lossless +reading and writing of JPEG files as DCT coefficient arrays. This ability +may be of use in other applications. + +Notes for programmers: +* We changed jpeg_start_decompress() to be able to suspend; this makes all +decoding modes available to suspending-input applications. However, +existing applications that use suspending input will need to be changed +to check the return value from jpeg_start_decompress(). You don't need to +do anything if you don't use a suspending data source. +* We changed the interface to the virtual array routines: access_virt_array +routines now take a count of the number of rows to access this time. The +last parameter to request_virt_array routines is now interpreted as the +maximum number of rows that may be accessed at once, but not necessarily +the height of every access. + + +Version 5b 15-Mar-95 +--------------------- + +Correct bugs with grayscale images having v_samp_factor > 1. + +jpeg_write_raw_data() now supports output suspension. + +Correct bugs in "configure" script for case of compiling in +a directory other than the one containing the source files. + +Repair bug in jquant1.c: sometimes didn't use as many colors as it could. + +Borland C makefile and jconfig file work under either MS-DOS or OS/2. + +Miscellaneous improvements to documentation. + + +Version 5a 7-Dec-94 +-------------------- + +Changed color conversion roundoff behavior so that grayscale values are +represented exactly. (This causes test image files to change.) + +Make ordered dither use 16x16 instead of 4x4 pattern for a small quality +improvement. + +New configure script based on latest GNU Autoconf. +Fix configure script to handle CFLAGS correctly. +Rename *.auto files to *.cfg, so that configure script still works if +file names have been truncated for DOS. + +Fix bug in rdbmp.c: didn't allow for extra data between header and image. + +Modify rdppm.c/wrppm.c to handle 2-byte raw PPM/PGM formats for 12-bit data. + +Fix several bugs in rdrle.c. + +NEED_SHORT_EXTERNAL_NAMES option was broken. + +Revise jerror.h/jerror.c for more flexibility in message table. + +Repair oversight in jmemname.c NO_MKTEMP case: file could be there +but unreadable. + + +Version 5 24-Sep-94 +-------------------- + +Version 5 represents a nearly complete redesign and rewrite of the IJG +software. Major user-visible changes include: + * Automatic configuration simplifies installation for most Unix systems. + * A range of speed vs. image quality tradeoffs are supported. + This includes resizing of an image during decompression: scaling down + by a factor of 1/2, 1/4, or 1/8 is handled very efficiently. + * New programs rdjpgcom and wrjpgcom allow insertion and extraction + of text comments in a JPEG file. + +The application programmer's interface to the library has changed completely. +Notable improvements include: + * We have eliminated the use of callback routines for handling the + uncompressed image data. The application now sees the library as a + set of routines that it calls to read or write image data on a + scanline-by-scanline basis. + * The application image data is represented in a conventional interleaved- + pixel format, rather than as a separate array for each color channel. + This can save a copying step in many programs. + * The handling of compressed data has been cleaned up: the application can + supply routines to source or sink the compressed data. It is possible to + suspend processing on source/sink buffer overrun, although this is not + supported in all operating modes. + * All static state has been eliminated from the library, so that multiple + instances of compression or decompression can be active concurrently. + * JPEG abbreviated datastream formats are supported, ie, quantization and + Huffman tables can be stored separately from the image data. + * And not only that, but the documentation of the library has improved + considerably! + + +The last widely used release before the version 5 rewrite was version 4A of +18-Feb-93. Change logs before that point have been discarded, since they +are not of much interest after the rewrite. diff --git a/src/gdcmjpeg/filelist.doc b/src/gdcmjpeg/filelist.doc new file mode 100644 index 00000000..9ba88e00 --- /dev/null +++ b/src/gdcmjpeg/filelist.doc @@ -0,0 +1,239 @@ +IJG JPEG LIBRARY: FILE LIST + +Copyright (C) 1994-1997, Thomas G. Lane. +This file is part of the Independent JPEG Group's software. +For conditions of distribution and use, see the accompanying README file. + + +Here is a road map to the files in the IJG JPEG distribution. The +distribution includes the JPEG library proper, plus two application +programs ("cjpeg" and "djpeg") which use the library to convert JPEG +files to and from some other popular image formats. A third application +"jpegtran" uses the library to do lossless conversion between different +variants of JPEG. There are also two stand-alone applications, +"rdjpgcom" and "wrjpgcom". + + +THE JPEG LIBRARY +================ + +Include files: + +jpeglib.h JPEG library's exported data and function declarations. +jconfig.h Configuration declarations. Note: this file is not present + in the distribution; it is generated during installation. +jmorecfg.h Additional configuration declarations; need not be changed + for a standard installation. +jerror.h Declares JPEG library's error and trace message codes. +jinclude.h Central include file used by all IJG .c files to reference + system include files. +jpegint.h JPEG library's internal data structures. +jlossls.h JPEG library's lossless codec data structures. +jlossy.h JPEG library's lossy codec structures. +jchuff.h Private declarations for Huffman encoder modules. +jdhuff.h Private declarations for Huffman decoder modules. +jdct.h Private declarations for forward & reverse DCT subsystems. +jmemsys.h Private declarations for memory management subsystem. +jversion.h Version information. + +Applications using the library should include jpeglib.h (which in turn +includes jconfig.h and jmorecfg.h). Optionally, jerror.h may be included +if the application needs to reference individual JPEG error codes. The +other include files are intended for internal use and would not normally +be included by an application program. (cjpeg/djpeg/etc do use jinclude.h, +since its function is to improve portability of the whole IJG distribution. +Most other applications will directly include the system include files they +want, and hence won't need jinclude.h.) + + +C source code files: + +These files contain most of the functions intended to be called directly by +an application program: + +jcapimin.c Application program interface: core routines for compression. +jcapistd.c Application program interface: standard compression. +jdapimin.c Application program interface: core routines for decompression. +jdapistd.c Application program interface: standard decompression. +jcomapi.c Application program interface routines common to compression + and decompression. +jcparam.c Compression parameter setting helper routines. +jctrans.c API and library routines for transcoding compression. +jdtrans.c API and library routines for transcoding decompression. + +Compression side of the library: + +jcinit.c Initialization: determines which other modules to use. +jcmaster.c Master control: setup and inter-pass sequencing logic. +jcmainct.c Main buffer controller (preprocessor => JPEG compressor). +jchuff.c Codec-independent Huffman entropy encoding routines. +jcprepct.c Preprocessor buffer controller. +jccolor.c Color space conversion. +jcsample.c Downsampling. +jcmarker.c JPEG marker writing. +jdatadst.c Data destination manager for stdio output. + +Lossy (DCT) codec: + +jlossy.c Lossy compressor proper. +jccoefct.c Buffer controller for DCT coefficient buffer. +jcdctmgr.c DCT manager (DCT implementation selection & control). +jfdctint.c Forward DCT using slow-but-accurate integer method. +jfdctfst.c Forward DCT using faster, less accurate integer method. +jfdctflt.c Forward DCT using floating-point arithmetic. +jcshuff.c Huffman entropy coding for sequential JPEG. +jcphuff.c Huffman entropy coding for progressive JPEG. + +Lossless (spatial) codec: + +jclossls.c Lossless compressor proper. +jcdiffct.c Buffer controller for difference buffer. +jcscale.c Point transformation. +jcpred.c Sample predictor and differencer. +jclhuff.c Huffman entropy encoding for lossless JPEG. + +Decompression side of the library: + +jdmaster.c Master control: determines which other modules to use. +jdinput.c Input controller: controls input processing modules. +jdmainct.c Main buffer controller (JPEG decompressor => postprocessor). +jdhuff.c Codec-independent Huffman entropy decoding routines. +jdpostct.c Postprocessor buffer controller. +jdmarker.c JPEG marker reading. +jdsample.c Upsampling. +jdcolor.c Color space conversion. +jdmerge.c Merged upsampling/color conversion (faster, lower quality). +jquant1.c One-pass color quantization using a fixed-spacing colormap. +jquant2.c Two-pass color quantization using a custom-generated colormap. + Also handles one-pass quantization to an externally given map. +jdatasrc.c Data source manager for stdio input. + +Lossy (DCT) codec: + +jdlossy.c Lossy decompressor proper. +jdcoefct.c Buffer controller for DCT coefficient buffer. +jdshuff.c Huffman entropy decoding for sequential JPEG. +jdphuff.c Huffman entropy decoding for progressive JPEG. +jddctmgr.c IDCT manager (IDCT implementation selection & control). +jidctint.c Inverse DCT using slow-but-accurate integer method. +jidctfst.c Inverse DCT using faster, less accurate integer method. +jidctflt.c Inverse DCT using floating-point arithmetic. +jidctred.c Inverse DCTs with reduced-size outputs. + +Lossless (spatial) codec: + +jdlossls.c Lossless decompressor proper. +jddiffct.c Buffer controller for difference buffers. +jdlhuff.c Huffman entropy decoding for lossless JPEG. +jdpred.c Sample predictor and undifferencer. +jdscale.c Point transformation, sample size scaling. + +Support files for both compression and decompression: + +jerror.c Standard error handling routines (application replaceable). +jmemmgr.c System-independent (more or less) memory management code. +jcodec.c Codec-independent utility routines. +jutils.c Miscellaneous utility routines. + +jmemmgr.c relies on a system-dependent memory management module. The IJG +distribution includes the following implementations of the system-dependent +module: + +jmemnobs.c "No backing store": assumes adequate virtual memory exists. +jmemansi.c Makes temporary files with ANSI-standard routine tmpfile(). +jmemname.c Makes temporary files with program-generated file names. +jmemdos.c Custom implementation for MS-DOS (16-bit environment only): + can use extended and expanded memory as well as temp files. +jmemmac.c Custom implementation for Apple Macintosh. + +Exactly one of the system-dependent modules should be configured into an +installed JPEG library (see install.doc for hints about which one to use). +On unusual systems you may find it worthwhile to make a special +system-dependent memory manager. + + +Non-C source code files: + +jmemdosa.asm 80x86 assembly code support for jmemdos.c; used only in + MS-DOS-specific configurations of the JPEG library. + + +CJPEG/DJPEG/JPEGTRAN +==================== + +Include files: + +cdjpeg.h Declarations shared by cjpeg/djpeg/jpegtran modules. +cderror.h Additional error and trace message codes for cjpeg et al. +transupp.h Declarations for jpegtran support routines in transupp.c. + +C source code files: + +cjpeg.c Main program for cjpeg. +djpeg.c Main program for djpeg. +jpegtran.c Main program for jpegtran. +cdjpeg.c Utility routines used by all three programs. +rdcolmap.c Code to read a colormap file for djpeg's "-map" switch. +rdswitch.c Code to process some of cjpeg's more complex switches. + Also used by jpegtran. +transupp.c Support code for jpegtran: lossless image manipulations. + +Image file reader modules for cjpeg: + +rdbmp.c BMP file input. +rdgif.c GIF file input (now just a stub). +rdppm.c PPM/PGM file input. +rdrle.c Utah RLE file input. +rdtarga.c Targa file input. + +Image file writer modules for djpeg: + +wrbmp.c BMP file output. +wrgif.c GIF file output (a mere shadow of its former self). +wrppm.c PPM/PGM file output. +wrrle.c Utah RLE file output. +wrtarga.c Targa file output. + + +RDJPGCOM/WRJPGCOM +================= + +C source code files: + +rdjpgcom.c Stand-alone rdjpgcom application. +wrjpgcom.c Stand-alone wrjpgcom application. + +These programs do not depend on the IJG library. They do use +jconfig.h and jinclude.h, only to improve portability. + + +ADDITIONAL FILES +================ + +Documentation (see README for a guide to the documentation files): + +README Master documentation file. +*.doc Other documentation files. +*.1 Documentation in Unix man page format. +change.log Version-to-version change highlights. +example.c Sample code for calling JPEG library. + +Configuration/installation files and programs (see install.doc for more info): + +configure Unix shell script to perform automatic configuration. +ltconfig Support scripts for configure (from GNU libtool). +ltmain.sh +config.guess +config.sub +install-sh Install shell script for those Unix systems lacking one. +ckconfig.c Program to generate jconfig.h on non-Unix systems. +jconfig.doc Template for making jconfig.h by hand. +makefile.* Sample makefiles for particular systems. +jconfig.* Sample jconfig.h for particular systems. +ansi2knr.c De-ANSIfier for pre-ANSI C compilers (courtesy of + L. Peter Deutsch and Aladdin Enterprises). + +Test files (see install.doc for test procedure): + +test*.* Source and comparison files for confidence test. + These are binary image files, NOT text files. diff --git a/src/gdcmjpeg/install.doc b/src/gdcmjpeg/install.doc new file mode 100644 index 00000000..3702b986 --- /dev/null +++ b/src/gdcmjpeg/install.doc @@ -0,0 +1,1063 @@ +INSTALLATION INSTRUCTIONS for the Independent JPEG Group's JPEG software + +Copyright (C) 1991-1998, Thomas G. Lane. +This file is part of the Independent JPEG Group's software. +For conditions of distribution and use, see the accompanying README file. + + +This file explains how to configure and install the IJG software. We have +tried to make this software extremely portable and flexible, so that it can be +adapted to almost any environment. The downside of this decision is that the +installation process is complicated. We have provided shortcuts to simplify +the task on common systems. But in any case, you will need at least a little +familiarity with C programming and program build procedures for your system. + +If you are only using this software as part of a larger program, the larger +program's installation procedure may take care of configuring the IJG code. +For example, Ghostscript's installation script will configure the IJG code. +You don't need to read this file if you just want to compile Ghostscript. + +If you are on a Unix machine, you may not need to read this file at all. +Try doing + ./configure + make + make test +If that doesn't complain, do + make install +(better do "make -n install" first to see if the makefile will put the files +where you want them). Read further if you run into snags or want to customize +the code for your system. + + +TABLE OF CONTENTS +----------------- + +Before you start +Configuring the software: + using the automatic "configure" script + using one of the supplied jconfig and makefile files + by hand +Building the software +Testing the software +Installing the software +Optional stuff +Optimization +Hints for specific systems + + +BEFORE YOU START +================ + +Before installing the software you must unpack the distributed source code. +Since you are reading this file, you have probably already succeeded in this +task. However, there is a potential for error if you needed to convert the +files to the local standard text file format (for example, if you are on +MS-DOS you may have converted LF end-of-line to CR/LF). You must apply +such conversion to all the files EXCEPT those whose names begin with "test". +The test files contain binary data; if you change them in any way then the +self-test will give bad results. + +Please check the last section of this file to see if there are hints for the +specific machine or compiler you are using. + + +CONFIGURING THE SOFTWARE +======================== + +To configure the IJG code for your system, you need to create two files: + * jconfig.h: contains values for system-dependent #define symbols. + * Makefile: controls the compilation process. +(On a non-Unix machine, you may create "project files" or some other +substitute for a Makefile. jconfig.h is needed in any environment.) + +We provide three different ways to generate these files: + * On a Unix system, you can just run the "configure" script. + * We provide sample jconfig files and makefiles for popular machines; + if your machine matches one of the samples, just copy the right sample + files to jconfig.h and Makefile. + * If all else fails, read the instructions below and make your own files. + + +Configuring the software using the automatic "configure" script +--------------------------------------------------------------- + +If you are on a Unix machine, you can just type + ./configure +and let the configure script construct appropriate configuration files. +If you're using "csh" on an old version of System V, you might need to type + sh configure +instead to prevent csh from trying to execute configure itself. +Expect configure to run for a few minutes, particularly on slower machines; +it works by compiling a series of test programs. + +Configure was created with GNU Autoconf and it follows the usual conventions +for GNU configure scripts. It makes a few assumptions that you may want to +override. You can do this by providing optional switches to configure: + +* If you want to build libjpeg as a shared library, say + ./configure --enable-shared +To get both shared and static libraries, say + ./configure --enable-shared --enable-static +Note that these switches invoke GNU libtool to take care of system-dependent +shared library building methods. If things don't work this way, please try +running configure without either switch; that should build a static library +without using libtool. If that works, your problem is probably with libtool +not with the IJG code. libtool is fairly new and doesn't support all flavors +of Unix yet. (You might be able to find a newer version of libtool than the +one included with libjpeg; see ftp.gnu.org. Report libtool problems to +bug-libtool@gnu.org.) + +* Configure will use gcc (GNU C compiler) if it's available, otherwise cc. +To force a particular compiler to be selected, use the CC option, for example + ./configure CC='cc' +The same method can be used to include any unusual compiler switches. +For example, on HP-UX you probably want to say + ./configure CC='cc -Aa' +to get HP's compiler to run in ANSI mode. + +* The default CFLAGS setting is "-O" for non-gcc compilers, "-O2" for gcc. +You can override this by saying, for example, + ./configure CFLAGS='-g' +if you want to compile with debugging support. + +* Configure will set up the makefile so that "make install" will install files +into /usr/local/bin, /usr/local/man, etc. You can specify an installation +prefix other than "/usr/local" by giving configure the option "--prefix=PATH". + +* If you don't have a lot of swap space, you may need to enable the IJG +software's internal virtual memory mechanism. To do this, give the option +"--enable-maxmem=N" where N is the default maxmemory limit in megabytes. +This is discussed in more detail under "Selecting a memory manager", below. +You probably don't need to worry about this on reasonably-sized Unix machines, +unless you plan to process very large images. + +Configure has some other features that are useful if you are cross-compiling +or working in a network of multiple machine types; but if you need those +features, you probably already know how to use them. + + +Configuring the software using one of the supplied jconfig and makefile files +----------------------------------------------------------------------------- + +If you have one of these systems, you can just use the provided configuration +files: + +Makefile jconfig file System and/or compiler + +makefile.manx jconfig.manx Amiga, Manx Aztec C +makefile.sas jconfig.sas Amiga, SAS C +makeproj.mac jconfig.mac Apple Macintosh, Metrowerks CodeWarrior +mak*jpeg.st jconfig.st Atari ST/STE/TT, Pure C or Turbo C +makefile.bcc jconfig.bcc MS-DOS or OS/2, Borland C +makefile.dj jconfig.dj MS-DOS, DJGPP (Delorie's port of GNU C) +makefile.mc6 jconfig.mc6 MS-DOS, Microsoft C (16-bit only) +makefile.wat jconfig.wat MS-DOS, OS/2, or Windows NT, Watcom C +makefile.vc jconfig.vc Windows NT/95, MS Visual C++ +make*.ds jconfig.vc Windows NT/95, MS Developer Studio +makefile.mms jconfig.vms Digital VMS, with MMS software +makefile.vms jconfig.vms Digital VMS, without MMS software + +Copy the proper jconfig file to jconfig.h and the makefile to Makefile (or +whatever your system uses as the standard makefile name). For more info see +the appropriate system-specific hints section near the end of this file. + + +Configuring the software by hand +-------------------------------- + +First, generate a jconfig.h file. If you are moderately familiar with C, +the comments in jconfig.doc should be enough information to do this; just +copy jconfig.doc to jconfig.h and edit it appropriately. Otherwise, you may +prefer to use the ckconfig.c program. You will need to compile and execute +ckconfig.c by hand --- we hope you know at least enough to do that. +ckconfig.c may not compile the first try (in fact, the whole idea is for it +to fail if anything is going to). If you get compile errors, fix them by +editing ckconfig.c according to the directions given in ckconfig.c. Once +you get it to run, it will write a suitable jconfig.h file, and will also +print out some advice about which makefile to use. + +You may also want to look at the canned jconfig files, if there is one for a +system similar to yours. + +Second, select a makefile and copy it to Makefile (or whatever your system +uses as the standard makefile name). The most generic makefiles we provide +are + makefile.ansi: if your C compiler supports function prototypes + makefile.unix: if not. +(You have function prototypes if ckconfig.c put "#define HAVE_PROTOTYPES" +in jconfig.h.) You may want to start from one of the other makefiles if +there is one for a system similar to yours. + +Look over the selected Makefile and adjust options as needed. In particular +you may want to change the CC and CFLAGS definitions. For instance, if you +are using GCC, set CC=gcc. If you had to use any compiler switches to get +ckconfig.c to work, make sure the same switches are in CFLAGS. + +If you are on a system that doesn't use makefiles, you'll need to set up +project files (or whatever you do use) to compile all the source files and +link them into executable files cjpeg, djpeg, jpegtran, rdjpgcom, and wrjpgcom. +See the file lists in any of the makefiles to find out which files go into +each program. Note that the provided makefiles all make a "library" file +libjpeg first, but you don't have to do that if you don't want to; the file +lists identify which source files are actually needed for compression, +decompression, or both. As a last resort, you can make a batch script that +just compiles everything and links it all together; makefile.vms is an example +of this (it's for VMS systems that have no make-like utility). + +Here are comments about some specific configuration decisions you'll +need to make: + +Command line style +------------------ + +These programs can use a Unix-like command line style which supports +redirection and piping, like this: + cjpeg inputfile >outputfile + cjpeg outputfile + source program | cjpeg >outputfile +The simpler "two file" command line style is just + cjpeg inputfile outputfile +You may prefer the two-file style, particularly if you don't have pipes. + +You MUST use two-file style on any system that doesn't cope well with binary +data fed through stdin/stdout; this is true for some MS-DOS compilers, for +example. If you're not on a Unix system, it's safest to assume you need +two-file style. (But if your compiler provides either the Posix-standard +fdopen() library routine or a Microsoft-compatible setmode() routine, you +can safely use the Unix command line style, by defining USE_FDOPEN or +USE_SETMODE respectively.) + +To use the two-file style, make jconfig.h say "#define TWO_FILE_COMMANDLINE". + +Selecting a memory manager +-------------------------- + +The IJG code is capable of working on images that are too big to fit in main +memory; data is swapped out to temporary files as necessary. However, the +code to do this is rather system-dependent. We provide five different +memory managers: + +* jmemansi.c This version uses the ANSI-standard library routine tmpfile(), + which not all non-ANSI systems have. On some systems + tmpfile() may put the temporary file in a non-optimal + location; if you don't like what it does, use jmemname.c. + +* jmemname.c This version creates named temporary files. For anything + except a Unix machine, you'll need to configure the + select_file_name() routine appropriately; see the comments + near the head of jmemname.c. If you use this version, define + NEED_SIGNAL_CATCHER in jconfig.h to make sure the temp files + are removed if the program is aborted. + +* jmemnobs.c (That stands for No Backing Store :-).) This will compile on + almost any system, but it assumes you have enough main memory + or virtual memory to hold the biggest images you work with. + +* jmemdos.c This should be used with most 16-bit MS-DOS compilers. + See the system-specific notes about MS-DOS for more info. + IMPORTANT: if you use this, define USE_MSDOS_MEMMGR in + jconfig.h, and include the assembly file jmemdosa.asm in the + programs. The supplied makefiles and jconfig files for + 16-bit MS-DOS compilers already do both. + +* jmemmac.c Custom version for Apple Macintosh; see the system-specific + notes for Macintosh for more info. + +To use a particular memory manager, change the SYSDEPMEM variable in your +makefile to equal the corresponding object file name (for example, jmemansi.o +or jmemansi.obj for jmemansi.c). + +If you have plenty of (real or virtual) main memory, just use jmemnobs.c. +"Plenty" means about ten bytes for every pixel in the largest images +you plan to process, so a lot of systems don't meet this criterion. +If yours doesn't, try jmemansi.c first. If that doesn't compile, you'll have +to use jmemname.c; be sure to adjust select_file_name() for local conditions. +You may also need to change unlink() to remove() in close_backing_store(). + +Except with jmemnobs.c or jmemmac.c, you need to adjust the DEFAULT_MAX_MEM +setting to a reasonable value for your system (either by adding a #define for +DEFAULT_MAX_MEM to jconfig.h, or by adding a -D switch to the Makefile). +This value limits the amount of data space the program will attempt to +allocate. Code and static data space isn't counted, so the actual memory +needs for cjpeg or djpeg are typically 100 to 150Kb more than the max-memory +setting. Larger max-memory settings reduce the amount of I/O needed to +process a large image, but too large a value can result in "insufficient +memory" failures. On most Unix machines (and other systems with virtual +memory), just set DEFAULT_MAX_MEM to several million and forget it. At the +other end of the spectrum, for MS-DOS machines you probably can't go much +above 300K to 400K. (On MS-DOS the value refers to conventional memory only. +Extended/expanded memory is handled separately by jmemdos.c.) + + +BUILDING THE SOFTWARE +===================== + +Now you should be able to compile the software. Just say "make" (or +whatever's necessary to start the compilation). Have a cup of coffee. + +Here are some things that could go wrong: + +If your compiler complains about undefined structures, you should be able to +shut it up by putting "#define INCOMPLETE_TYPES_BROKEN" in jconfig.h. + +If you have trouble with missing system include files or inclusion of the +wrong ones, read jinclude.h. This shouldn't happen if you used configure +or ckconfig.c to set up jconfig.h. + +There are a fair number of routines that do not use all of their parameters; +some compilers will issue warnings about this, which you can ignore. There +are also a few configuration checks that may give "unreachable code" warnings. +Any other warning deserves investigation. + +If you don't have a getenv() library routine, define NO_GETENV. + +Also see the system-specific hints, below. + + +TESTING THE SOFTWARE +==================== + +As a quick test of functionality we've included a small sample image in +several forms: + testorig.jpg Starting point for the djpeg tests. + testimg.ppm The output of djpeg testorig.jpg + testimg.bmp The output of djpeg -bmp -colors 256 testorig.jpg + testimg.jpg The output of cjpeg testimg.ppm + testprog.jpg Progressive-mode equivalent of testorig.jpg. + testimgp.jpg The output of cjpeg -progressive -optimize testimg.ppm +(The first- and second-generation .jpg files aren't identical since JPEG is +lossy.) If you can generate duplicates of the testimg* files then you +probably have working programs. + +With most of the makefiles, "make test" will perform the necessary +comparisons. + +If you're using a makefile that doesn't provide the test option, run djpeg +and cjpeg by hand and compare the output files to testimg* with whatever +binary file comparison tool you have. The files should be bit-for-bit +identical. + +If the programs complain "MAX_ALLOC_CHUNK is wrong, please fix", then you +need to reduce MAX_ALLOC_CHUNK to a value that fits in type size_t. +Try adding "#define MAX_ALLOC_CHUNK 65520L" to jconfig.h. A less likely +configuration error is "ALIGN_TYPE is wrong, please fix": defining ALIGN_TYPE +as long should take care of that one. + +If the cjpeg test run fails with "Missing Huffman code table entry", it's a +good bet that you needed to define RIGHT_SHIFT_IS_UNSIGNED. Go back to the +configuration step and run ckconfig.c. (This is a good plan for any other +test failure, too.) + +If you are using Unix (one-file) command line style on a non-Unix system, +it's a good idea to check that binary I/O through stdin/stdout actually +works. You should get the same results from "djpeg out.ppm" +as from "djpeg -outfile out.ppm testorig.jpg". Note that the makefiles all +use the latter style and therefore do not exercise stdin/stdout! If this +check fails, try recompiling with USE_SETMODE or USE_FDOPEN defined. +If it still doesn't work, better use two-file style. + +If you chose a memory manager other than jmemnobs.c, you should test that +temporary-file usage works. Try "djpeg -bmp -colors 256 -max 0 testorig.jpg" +and make sure its output matches testimg.bmp. If you have any really large +images handy, try compressing them with -optimize and/or decompressing with +-colors 256 to make sure your DEFAULT_MAX_MEM setting is not too large. + +NOTE: this is far from an exhaustive test of the JPEG software; some modules, +such as 1-pass color quantization, are not exercised at all. It's just a +quick test to give you some confidence that you haven't missed something +major. + + +INSTALLING THE SOFTWARE +======================= + +Once you're done with the above steps, you can install the software by +copying the executable files (cjpeg, djpeg, jpegtran, rdjpgcom, and wrjpgcom) +to wherever you normally install programs. On Unix systems, you'll also want +to put the man pages (cjpeg.1, djpeg.1, jpegtran.1, rdjpgcom.1, wrjpgcom.1) +in the man-page directory. The pre-fab makefiles don't support this step +since there's such a wide variety of installation procedures on different +systems. + +If you generated a Makefile with the "configure" script, you can just say + make install +to install the programs and their man pages into the standard places. +(You'll probably need to be root to do this.) We recommend first saying + make -n install +to see where configure thought the files should go. You may need to edit +the Makefile, particularly if your system's conventions for man page +filenames don't match what configure expects. + +If you want to install the IJG library itself, for use in compiling other +programs besides ours, then you need to put the four include files + jpeglib.h jerror.h jconfig.h jmorecfg.h +into your include-file directory, and put the library file libjpeg.a +(extension may vary depending on system) wherever library files go. +If you generated a Makefile with "configure", it will do what it thinks +is the right thing if you say + make install-lib + + +OPTIONAL STUFF +============== + +Progress monitor: + +If you like, you can #define PROGRESS_REPORT (in jconfig.h) to enable display +of percent-done progress reports. The routine provided in cdjpeg.c merely +prints percentages to stderr, but you can customize it to do something +fancier. + +Utah RLE file format support: + +We distribute the software with support for RLE image files (Utah Raster +Toolkit format) disabled, because the RLE support won't compile without the +Utah library. If you have URT version 3.1 or later, you can enable RLE +support as follows: + 1. #define RLE_SUPPORTED in jconfig.h. + 2. Add a -I option to CFLAGS in the Makefile for the directory + containing the URT .h files (typically the "include" + subdirectory of the URT distribution). + 3. Add -L... -lrle to LDLIBS in the Makefile, where ... specifies + the directory containing the URT "librle.a" file (typically the + "lib" subdirectory of the URT distribution). + +Support for 12-bit-deep pixel data: + +The JPEG standard allows either 8-bit or 12-bit data precision. (For color, +this means 8 or 12 bits per channel, of course.) If you need to work with +deeper than 8-bit data, you can compile the IJG code for 12-bit operation. +To do so: + 1. In jmorecfg.h, define BITS_IN_JSAMPLE as 12 rather than 8. + 2. In jconfig.h, undefine BMP_SUPPORTED, RLE_SUPPORTED, and TARGA_SUPPORTED, + because the code for those formats doesn't handle 12-bit data and won't + even compile. (The PPM code does work, as explained below. The GIF + code works too; it scales 8-bit GIF data to and from 12-bit depth + automatically.) + 3. Compile. Don't expect "make test" to pass, since the supplied test + files are for 8-bit data. + +Currently, 12-bit support does not work on 16-bit-int machines. + +Note that a 12-bit version will not read 8-bit JPEG files, nor vice versa; +so you'll want to keep around a regular 8-bit compilation as well. +(Run-time selection of data depth, to allow a single copy that does both, +is possible but would probably slow things down considerably; it's very low +on our to-do list.) + +The PPM reader (rdppm.c) can read 12-bit data from either text-format or +binary-format PPM and PGM files. Binary-format PPM/PGM files which have a +maxval greater than 255 are assumed to use 2 bytes per sample, LSB first +(little-endian order). As of early 1995, 2-byte binary format is not +officially supported by the PBMPLUS library, but it is expected that a +future release of PBMPLUS will support it. Note that the PPM reader will +read files of any maxval regardless of the BITS_IN_JSAMPLE setting; incoming +data is automatically rescaled to either maxval=255 or maxval=4095 as +appropriate for the cjpeg bit depth. + +The PPM writer (wrppm.c) will normally write 2-byte binary PPM or PGM +format, maxval 4095, when compiled with BITS_IN_JSAMPLE=12. Since this +format is not yet widely supported, you can disable it by compiling wrppm.c +with PPM_NORAWWORD defined; then the data is scaled down to 8 bits to make a +standard 1-byte/sample PPM or PGM file. (Yes, this means still another copy +of djpeg to keep around. But hopefully you won't need it for very long. +Poskanzer's supposed to get that new PBMPLUS release out Real Soon Now.) + +Of course, if you are working with 12-bit data, you probably have it stored +in some other, nonstandard format. In that case you'll probably want to +write your own I/O modules to read and write your format. + +Note that a 12-bit version of cjpeg always runs in "-optimize" mode, in +order to generate valid Huffman tables. This is necessary because our +default Huffman tables only cover 8-bit data. + +Removing code: + +If you need to make a smaller version of the JPEG software, some optional +functions can be removed at compile time. See the xxx_SUPPORTED #defines in +jconfig.h and jmorecfg.h. If at all possible, we recommend that you leave in +decoder support for all valid JPEG files, to ensure that you can read anyone's +output. Taking out support for image file formats that you don't use is the +most painless way to make the programs smaller. Another possibility is to +remove some of the DCT methods: in particular, the "IFAST" method may not be +enough faster than the others to be worth keeping on your machine. (If you +do remove ISLOW or IFAST, be sure to redefine JDCT_DEFAULT or JDCT_FASTEST +to a supported method, by adding a #define in jconfig.h.) + + +OPTIMIZATION +============ + +Unless you own a Cray, you'll probably be interested in making the JPEG +software go as fast as possible. This section covers some machine-dependent +optimizations you may want to try. We suggest that before trying any of +this, you first get the basic installation to pass the self-test step. +Repeat the self-test after any optimization to make sure that you haven't +broken anything. + +The integer DCT routines perform a lot of multiplications. These +multiplications must yield 32-bit results, but none of their input values +are more than 16 bits wide. On many machines, notably the 680x0 and 80x86 +CPUs, a 16x16=>32 bit multiply instruction is faster than a full 32x32=>32 +bit multiply. Unfortunately there is no portable way to specify such a +multiplication in C, but some compilers can generate one when you use the +right combination of casts. See the MULTIPLYxxx macro definitions in +jdct.h. If your compiler makes "int" be 32 bits and "short" be 16 bits, +defining SHORTxSHORT_32 is fairly likely to work. When experimenting with +alternate definitions, be sure to test not only whether the code still works +(use the self-test), but also whether it is actually faster --- on some +compilers, alternate definitions may compute the right answer, yet be slower +than the default. Timing cjpeg on a large PGM (grayscale) input file is the +best way to check this, as the DCT will be the largest fraction of the runtime +in that mode. (Note: some of the distributed compiler-specific jconfig files +already contain #define switches to select appropriate MULTIPLYxxx +definitions.) + +If your machine has sufficiently fast floating point hardware, you may find +that the float DCT method is faster than the integer DCT methods, even +after tweaking the integer multiply macros. In that case you may want to +make the float DCT be the default method. (The only objection to this is +that float DCT results may vary slightly across machines.) To do that, add +"#define JDCT_DEFAULT JDCT_FLOAT" to jconfig.h. Even if you don't change +the default, you should redefine JDCT_FASTEST, which is the method selected +by djpeg's -fast switch. Don't forget to update the documentation files +(usage.doc and/or cjpeg.1, djpeg.1) to agree with what you've done. + +If access to "short" arrays is slow on your machine, it may be a win to +define type JCOEF as int rather than short. This will cost a good deal of +memory though, particularly in some multi-pass modes, so don't do it unless +you have memory to burn and short is REALLY slow. + +If your compiler can compile function calls in-line, make sure the INLINE +macro in jmorecfg.h is defined as the keyword that marks a function +inline-able. Some compilers have a switch that tells the compiler to inline +any function it thinks is profitable (e.g., -finline-functions for gcc). +Enabling such a switch is likely to make the compiled code bigger but faster. + +In general, it's worth trying the maximum optimization level of your compiler, +and experimenting with any optional optimizations such as loop unrolling. +(Unfortunately, far too many compilers have optimizer bugs ... be prepared to +back off if the code fails self-test.) If you do any experimentation along +these lines, please report the optimal settings to jpeg-info@uunet.uu.net so +we can mention them in future releases. Be sure to specify your machine and +compiler version. + + +HINTS FOR SPECIFIC SYSTEMS +========================== + +We welcome reports on changes needed for systems not mentioned here. Submit +'em to jpeg-info@uunet.uu.net. Also, if configure or ckconfig.c is wrong +about how to configure the JPEG software for your system, please let us know. + + +Acorn RISC OS: + +(Thanks to Simon Middleton for these hints on compiling with Desktop C.) +After renaming the files according to Acorn conventions, take a copy of +makefile.ansi, change all occurrences of 'libjpeg.a' to 'libjpeg.o' and +change these definitions as indicated: + +CFLAGS= -throwback -IC: -Wn +LDLIBS=C:o.Stubs +SYSDEPMEM=jmemansi.o +LN=Link +AR=LibFile -c -o + +Also add a new line '.c.o:; $(cc) $< $(cflags) -c -o $@'. Remove the +lines '$(RM) libjpeg.o' and '$(AR2) libjpeg.o' and the 'jconfig.h' +dependency section. + +Copy jconfig.doc to jconfig.h. Edit jconfig.h to define TWO_FILE_COMMANDLINE +and CHAR_IS_UNSIGNED. + +Run the makefile using !AMU not !Make. If you want to use the 'clean' and +'test' makefile entries then you will have to fiddle with the syntax a bit +and rename the test files. + + +Amiga: + +SAS C 6.50 reportedly is too buggy to compile the IJG code properly. +A patch to update to 6.51 is available from SAS or AmiNet FTP sites. + +The supplied config files are set up to use jmemname.c as the memory +manager, with temporary files being created on the device named by +"JPEGTMP:". + + +Atari ST/STE/TT: + +Copy the project files makcjpeg.st, makdjpeg.st, maktjpeg.st, and makljpeg.st +to cjpeg.prj, djpeg.prj, jpegtran.prj, and libjpeg.prj respectively. The +project files should work as-is with Pure C. For Turbo C, change library +filenames "pc..." to "tc..." in each project file. Note that libjpeg.prj +selects jmemansi.c as the recommended memory manager. You'll probably want to +adjust the DEFAULT_MAX_MEM setting --- you want it to be a couple hundred K +less than your normal free memory. Put "#define DEFAULT_MAX_MEM nnnn" into +jconfig.h to do this. + +To use the 68881/68882 coprocessor for the floating point DCT, add the +compiler option "-8" to the project files and replace pcfltlib.lib with +pc881lib.lib in cjpeg.prj and djpeg.prj. Or if you don't have a +coprocessor, you may prefer to remove the float DCT code by undefining +DCT_FLOAT_SUPPORTED in jmorecfg.h (since without a coprocessor, the float +code will be too slow to be useful). In that case, you can delete +pcfltlib.lib from the project files. + +Note that you must make libjpeg.lib before making cjpeg.ttp, djpeg.ttp, +or jpegtran.ttp. You'll have to perform the self-test by hand. + +We haven't bothered to include project files for rdjpgcom and wrjpgcom. +Those source files should just be compiled by themselves; they don't +depend on the JPEG library. + +There is a bug in some older versions of the Turbo C library which causes the +space used by temporary files created with "tmpfile()" not to be freed after +an abnormal program exit. If you check your disk afterwards, you will find +cluster chains that are allocated but not used by a file. This should not +happen in cjpeg/djpeg/jpegtran, since we enable a signal catcher to explicitly +close temp files before exiting. But if you use the JPEG library with your +own code, be sure to supply a signal catcher, or else use a different +system-dependent memory manager. + + +Cray: + +Should you be so fortunate as to be running JPEG on a Cray YMP, there is a +compiler bug in old versions of Cray's Standard C (prior to 3.1). If you +still have an old compiler, you'll need to insert a line reading +"#pragma novector" just before the loop + for (i = 1; i <= (int) htbl->bits[l]; i++) + huffsize[p++] = (char) l; +in fix_huff_tbl (in V5beta1, line 204 of jchuff.c and line 176 of jdhuff.c). +[This bug may or may not still occur with the current IJG code, but it's +probably a dead issue anyway...] + + +HP-UX: + +If you have HP-UX 7.05 or later with the "software development" C compiler, +you should run the compiler in ANSI mode. If using the configure script, +say + ./configure CC='cc -Aa' +(or -Ae if you prefer). If configuring by hand, use makefile.ansi and add +"-Aa" to the CFLAGS line in the makefile. + +If you have a pre-7.05 system, or if you are using the non-ANSI C compiler +delivered with a minimum HP-UX system, then you must use makefile.unix +(and do NOT add -Aa); or just run configure without the CC option. + +On HP 9000 series 800 machines, the HP C compiler is buggy in revisions prior +to A.08.07. If you get complaints about "not a typedef name", you'll have to +use makefile.unix, or run configure without the CC option. + + +Macintosh, generic comments: + +The supplied user-interface files (cjpeg.c, djpeg.c, etc) are set up to +provide a Unix-style command line interface. You can use this interface on +the Mac by means of the ccommand() library routine provided by Metrowerks +CodeWarrior or Think C. This is only appropriate for testing the library, +however; to make a user-friendly equivalent of cjpeg/djpeg you'd really want +to develop a Mac-style user interface. There isn't a complete example +available at the moment, but there are some helpful starting points: +1. Sam Bushell's free "To JPEG" applet provides drag-and-drop conversion to +JPEG under System 7 and later. This only illustrates how to use the +compression half of the library, but it does a very nice job of that part. +The CodeWarrior source code is available from http://www.pobox.com/~jsam. +2. Jim Brunner prepared a Mac-style user interface for both compression and +decompression. Unfortunately, it hasn't been updated since IJG v4, and +the library's API has changed considerably since then. Still it may be of +some help, particularly as a guide to compiling the IJG code under Think C. +Jim's code is available from the Info-Mac archives, at sumex-aim.stanford.edu +or mirrors thereof; see file /info-mac/dev/src/jpeg-convert-c.hqx. + +jmemmac.c is the recommended memory manager back end for Macintosh. It uses +NewPtr/DisposePtr instead of malloc/free, and has a Mac-specific +implementation of jpeg_mem_available(). It also creates temporary files that +follow Mac conventions. (That part of the code relies on System-7-or-later OS +functions. See the comments in jmemmac.c if you need to run it on System 6.) +NOTE that USE_MAC_MEMMGR must be defined in jconfig.h to use jmemmac.c. + +You can also use jmemnobs.c, if you don't care about handling images larger +than available memory. If you use any memory manager back end other than +jmemmac.c, we recommend replacing "malloc" and "free" by "NewPtr" and +"DisposePtr", because Mac C libraries often have peculiar implementations of +malloc/free. (For instance, free() may not return the freed space to the +Mac Memory Manager. This is undesirable for the IJG code because jmemmgr.c +already clumps space requests.) + + +Macintosh, Metrowerks CodeWarrior: + +The Unix-command-line-style interface can be used by defining USE_CCOMMAND. +You'll also need to define TWO_FILE_COMMANDLINE to avoid stdin/stdout. +This means that when using the cjpeg/djpeg programs, you'll have to type the +input and output file names in the "Arguments" text-edit box, rather than +using the file radio buttons. (Perhaps USE_FDOPEN or USE_SETMODE would +eliminate the problem, but I haven't heard from anyone who's tried it.) + +On 680x0 Macs, Metrowerks defines type "double" as a 10-byte IEEE extended +float. jmemmgr.c won't like this: it wants sizeof(ALIGN_TYPE) to be a power +of 2. Add "#define ALIGN_TYPE long" to jconfig.h to eliminate the complaint. + +The supplied configuration file jconfig.mac can be used for your jconfig.h; +it includes all the recommended symbol definitions. If you have AppleScript +installed, you can run the supplied script makeproj.mac to create CodeWarrior +project files for the library and the testbed applications, then build the +library and applications. (Thanks to Dan Sears and Don Agro for this nifty +hack, which saves us from trying to maintain CodeWarrior project files as part +of the IJG distribution...) + + +Macintosh, Think C: + +The documentation in Jim Brunner's "JPEG Convert" source code (see above) +includes detailed build instructions for Think C; it's probably somewhat +out of date for the current release, but may be helpful. + +If you want to build the minimal command line version, proceed as follows. +You'll have to prepare project files for the programs; we don't include any +in the distribution since they are not text files. Use the file lists in +any of the supplied makefiles as a guide. Also add the ANSI and Unix C +libraries in a separate segment. You may need to divide the JPEG files into +more than one segment; we recommend dividing compression and decompression +modules. Define USE_CCOMMAND in jconfig.h so that the ccommand() routine is +called. You must also define TWO_FILE_COMMANDLINE because stdin/stdout +don't handle binary data correctly. + +On 680x0 Macs, Think C defines type "double" as a 12-byte IEEE extended float. +jmemmgr.c won't like this: it wants sizeof(ALIGN_TYPE) to be a power of 2. +Add "#define ALIGN_TYPE long" to jconfig.h to eliminate the complaint. + +jconfig.mac should work as a jconfig.h configuration file for Think C, +but the makeproj.mac AppleScript script is specific to CodeWarrior. Sorry. + + +MIPS R3000: + +MIPS's cc version 1.31 has a rather nasty optimization bug. Don't use -O +if you have that compiler version. (Use "cc -V" to check the version.) +Note that the R3000 chip is found in workstations from DEC and others. + + +MS-DOS, generic comments for 16-bit compilers: + +The IJG code is designed to work well in 80x86 "small" or "medium" memory +models (i.e., data pointers are 16 bits unless explicitly declared "far"; +code pointers can be either size). You may be able to use small model to +compile cjpeg or djpeg by itself, but you will probably have to use medium +model for any larger application. This won't make much difference in +performance. You *will* take a noticeable performance hit if you use a +large-data memory model, and you should avoid "huge" model if at all +possible. Be sure that NEED_FAR_POINTERS is defined in jconfig.h if you use +a small-data memory model; be sure it is NOT defined if you use a large-data +model. (The supplied makefiles and jconfig files for Borland and Microsoft C +compile in medium model and define NEED_FAR_POINTERS.) + +The DOS-specific memory manager, jmemdos.c, should be used if possible. +It needs some assembly-code routines which are in jmemdosa.asm; make sure +your makefile assembles that file and includes it in the library. If you +don't have a suitable assembler, you can get pre-assembled object files for +jmemdosa by FTP from ftp.uu.net:/graphics/jpeg/jdosaobj.zip. (DOS-oriented +distributions of the IJG source code often include these object files.) + +When using jmemdos.c, jconfig.h must define USE_MSDOS_MEMMGR and must set +MAX_ALLOC_CHUNK to less than 64K (65520L is a typical value). If your +C library's far-heap malloc() can't allocate blocks that large, reduce +MAX_ALLOC_CHUNK to whatever it can handle. + +If you can't use jmemdos.c for some reason --- for example, because you +don't have an assembler to assemble jmemdosa.asm --- you'll have to fall +back to jmemansi.c or jmemname.c. You'll probably still need to set +MAX_ALLOC_CHUNK in jconfig.h, because most DOS C libraries won't malloc() +more than 64K at a time. IMPORTANT: if you use jmemansi.c or jmemname.c, +you will have to compile in a large-data memory model in order to get the +right stdio library. Too bad. + +wrjpgcom needs to be compiled in large model, because it malloc()s a 64KB +work area to hold the comment text. If your C library's malloc can't +handle that, reduce MAX_COM_LENGTH as necessary in wrjpgcom.c. + +Most MS-DOS compilers treat stdin/stdout as text files, so you must use +two-file command line style. But if your compiler has either fdopen() or +setmode(), you can use one-file style if you like. To do this, define +USE_SETMODE or USE_FDOPEN so that stdin/stdout will be set to binary mode. +(USE_SETMODE seems to work with more DOS compilers than USE_FDOPEN.) You +should test that I/O through stdin/stdout produces the same results as I/O +to explicitly named files... the "make test" procedures in the supplied +makefiles do NOT use stdin/stdout. + + +MS-DOS, generic comments for 32-bit compilers: + +None of the above comments about memory models apply if you are using a +32-bit flat-memory-space environment, such as DJGPP or Watcom C. (And you +should use one if you have it, as performance will be much better than +8086-compatible code!) For flat-memory-space compilers, do NOT define +NEED_FAR_POINTERS, and do NOT use jmemdos.c. Use jmemnobs.c if the +environment supplies adequate virtual memory, otherwise use jmemansi.c or +jmemname.c. + +You'll still need to be careful about binary I/O through stdin/stdout. +See the last paragraph of the previous section. + + +MS-DOS, Borland C: + +Be sure to convert all the source files to DOS text format (CR/LF newlines). +Although Borland C will often work OK with unmodified Unix (LF newlines) +source files, sometimes it will give bogus compile errors. +"Illegal character '#'" is the most common such error. (This is true with +Borland C 3.1, but perhaps is fixed in newer releases.) + +If you want one-file command line style, just undefine TWO_FILE_COMMANDLINE. +jconfig.bcc already includes #define USE_SETMODE to make this work. +(fdopen does not work correctly.) + + +MS-DOS, Microsoft C: + +makefile.mc6 works with Microsoft C, DOS Visual C++, etc. It should only +be used if you want to build a 16-bit (small or medium memory model) program. + +If you want one-file command line style, just undefine TWO_FILE_COMMANDLINE. +jconfig.mc6 already includes #define USE_SETMODE to make this work. +(fdopen does not work correctly.) + +Note that this makefile assumes that the working copy of itself is called +"makefile". If you want to call it something else, say "makefile.mak", +be sure to adjust the dependency line that reads "$(RFILE) : makefile". +Otherwise the make will fail because it doesn't know how to create "makefile". +Worse, some releases of Microsoft's make utilities give an incorrect error +message in this situation. + +Old versions of MS C fail with an "out of macro expansion space" error +because they can't cope with the macro TRACEMS8 (defined in jerror.h). +If this happens to you, the easiest solution is to change TRACEMS8 to +expand to nothing. You'll lose the ability to dump out JPEG coefficient +tables with djpeg -debug -debug, but at least you can compile. + +Original MS C 6.0 is very buggy; it compiles incorrect code unless you turn +off optimization entirely (remove -O from CFLAGS). 6.00A is better, but it +still generates bad code if you enable loop optimizations (-Ol or -Ox). + +MS C 8.0 crashes when compiling jquant1.c with optimization switch /Oo ... +which is on by default. To work around this bug, compile that one file +with /Oo-. + + +Microsoft Windows (all versions), generic comments: + +Some Windows system include files define typedef boolean as "unsigned char". +The IJG code also defines typedef boolean, but we make it "int" by default. +This doesn't affect the IJG programs because we don't import those Windows +include files. But if you use the JPEG library in your own program, and some +of your program's files import one definition of boolean while some import the +other, you can get all sorts of mysterious problems. A good preventive step +is to make the IJG library use "unsigned char" for boolean. To do that, +add something like this to your jconfig.h file: + /* Define "boolean" as unsigned char, not int, per Windows custom */ + #ifndef __RPCNDR_H__ /* don't conflict if rpcndr.h already read */ + typedef unsigned char boolean; + #endif + #define HAVE_BOOLEAN /* prevent jmorecfg.h from redefining it */ +(This is already in jconfig.vc, by the way.) + +windef.h contains the declarations + #define far + #define FAR far +Since jmorecfg.h tries to define FAR as empty, you may get a compiler +warning if you include both jpeglib.h and windef.h (which windows.h +includes). To suppress the warning, you can put "#ifndef FAR"/"#endif" +around the line "#define FAR" in jmorecfg.h. + +When using the library in a Windows application, you will almost certainly +want to modify or replace the error handler module jerror.c, since our +default error handler does a couple of inappropriate things: + 1. it tries to write error and warning messages on stderr; + 2. in event of a fatal error, it exits by calling exit(). + +A simple stopgap solution for problem 1 is to replace the line + fprintf(stderr, "%s\n", buffer); +(in output_message in jerror.c) with + MessageBox(GetActiveWindow(),buffer,"JPEG Error",MB_OK|MB_ICONERROR); +It's highly recommended that you at least do that much, since otherwise +error messages will disappear into nowhere. (Beginning with IJG v6b, this +code is already present in jerror.c; just define USE_WINDOWS_MESSAGEBOX in +jconfig.h to enable it.) + +The proper solution for problem 2 is to return control to your calling +application after a library error. This can be done with the setjmp/longjmp +technique discussed in libjpeg.doc and illustrated in example.c. (NOTE: +some older Windows C compilers provide versions of setjmp/longjmp that +don't actually work under Windows. You may need to use the Windows system +functions Catch and Throw instead.) + +The recommended memory manager under Windows is jmemnobs.c; in other words, +let Windows do any virtual memory management needed. You should NOT use +jmemdos.c nor jmemdosa.asm under Windows. + +For Windows 3.1, we recommend compiling in medium or large memory model; +for newer Windows versions, use a 32-bit flat memory model. (See the MS-DOS +sections above for more info about memory models.) In the 16-bit memory +models only, you'll need to put + #define MAX_ALLOC_CHUNK 65520L /* Maximum request to malloc() */ +into jconfig.h to limit allocation chunks to 64Kb. (Without that, you'd +have to use huge memory model, which slows things down unnecessarily.) +jmemnobs.c works without modification in large or flat memory models, but to +use medium model, you need to modify its jpeg_get_large and jpeg_free_large +routines to allocate far memory. In any case, you might like to replace +its calls to malloc and free with direct calls on Windows memory allocation +functions. + +You may also want to modify jdatasrc.c and jdatadst.c to use Windows file +operations rather than fread/fwrite. This is only necessary if your C +compiler doesn't provide a competent implementation of C stdio functions. + +You might want to tweak the RGB_xxx macros in jmorecfg.h so that the library +will accept or deliver color pixels in BGR sample order, not RGB; BGR order +is usually more convenient under Windows. Note that this change will break +the sample applications cjpeg/djpeg, but the library itself works fine. + + +Many people want to convert the IJG library into a DLL. This is reasonably +straightforward, but watch out for the following: + + 1. Don't try to compile as a DLL in small or medium memory model; use +large model, or even better, 32-bit flat model. Many places in the IJG code +assume the address of a local variable is an ordinary (not FAR) pointer; +that isn't true in a medium-model DLL. + + 2. Microsoft C cannot pass file pointers between applications and DLLs. +(See Microsoft Knowledge Base, PSS ID Number Q50336.) So jdatasrc.c and +jdatadst.c don't work if you open a file in your application and then pass +the pointer to the DLL. One workaround is to make jdatasrc.c/jdatadst.c +part of your main application rather than part of the DLL. + + 3. You'll probably need to modify the macros GLOBAL() and EXTERN() to +attach suitable linkage keywords to the exported routine names. Similarly, +you'll want to modify METHODDEF() and JMETHOD() to ensure function pointers +are declared in a way that lets application routines be called back through +the function pointers. These macros are in jmorecfg.h. Typical definitions +for a 16-bit DLL are: + #define GLOBAL(type) type _far _pascal _loadds _export + #define EXTERN(type) extern type _far _pascal _loadds + #define METHODDEF(type) static type _far _pascal + #define JMETHOD(type,methodname,arglist) \ + type (_far _pascal *methodname) arglist +For a 32-bit DLL you may want something like + #define GLOBAL(type) __declspec(dllexport) type + #define EXTERN(type) extern __declspec(dllexport) type +Although not all the GLOBAL routines are actually intended to be called by +the application, the performance cost of making them all DLL entry points is +negligible. + +The unmodified IJG library presents a very C-specific application interface, +so the resulting DLL is only usable from C or C++ applications. There has +been some talk of writing wrapper code that would present a simpler interface +usable from other languages, such as Visual Basic. This is on our to-do list +but hasn't been very high priority --- any volunteers out there? + + +Microsoft Windows, Borland C: + +The provided jconfig.bcc should work OK in a 32-bit Windows environment, +but you'll need to tweak it in a 16-bit environment (you'd need to define +NEED_FAR_POINTERS and MAX_ALLOC_CHUNK). Beware that makefile.bcc will need +alteration if you want to use it for Windows --- in particular, you should +use jmemnobs.c not jmemdos.c under Windows. + +Borland C++ 4.5 fails with an internal compiler error when trying to compile +jdmerge.c in 32-bit mode. If enough people complain, perhaps Borland will fix +it. In the meantime, the simplest known workaround is to add a redundant +definition of the variable range_limit in h2v1_merged_upsample(), at the head +of the block that handles odd image width (about line 268 in v6 jdmerge.c): + /* If image width is odd, do the last output column separately */ + if (cinfo->output_width & 1) { + register JSAMPLE * range_limit = cinfo->sample_range_limit; /* ADD THIS */ + cb = GETJSAMPLE(*inptr1); +Pretty bizarre, especially since the very similar routine h2v2_merged_upsample +doesn't trigger the bug. +Recent reports suggest that this bug does not occur with "bcc32a" (the +Pentium-optimized version of the compiler). + +Another report from a user of Borland C 4.5 was that incorrect code (leading +to a color shift in processed images) was produced if any of the following +optimization switch combinations were used: + -Ot -Og + -Ot -Op + -Ot -Om +So try backing off on optimization if you see such a problem. (Are there +several different releases all numbered "4.5"??) + + +Microsoft Windows, Microsoft Visual C++: + +jconfig.vc should work OK with any Microsoft compiler for a 32-bit memory +model. makefile.vc is intended for command-line use. (If you are using +the Developer Studio environment, you may prefer the DevStudio project +files; see below.) + +Some users feel that it's easier to call the library from C++ code if you +force VC++ to treat the library as C++ code, which you can do by renaming +all the *.c files to *.cpp (and adjusting the makefile to match). This +avoids the need to put extern "C" { ... } around #include "jpeglib.h" in +your C++ application. + + +Microsoft Windows, Microsoft Developer Studio: + +We include makefiles that should work as project files in DevStudio 4.2 or +later. There is a library makefile that builds the IJG library as a static +Win32 library, and an application makefile that builds the sample applications +as Win32 console applications. (Even if you only want the library, we +recommend building the applications so that you can run the self-test.) + +To use: +1. Copy jconfig.vc to jconfig.h, makelib.ds to jpeg.mak, and + makeapps.ds to apps.mak. (Note that the renaming is critical!) +2. Click on the .mak files to construct project workspaces. + (If you are using DevStudio more recent than 4.2, you'll probably + get a message saying that the makefiles are being updated.) +3. Build the library project, then the applications project. +4. Move the application .exe files from `app`\Release to an + appropriate location on your path. +5. To perform the self-test, execute the command line + NMAKE /f makefile.vc test + + +OS/2, Borland C++: + +Watch out for optimization bugs in older Borland compilers; you may need +to back off the optimization switch settings. See the comments in +makefile.bcc. + + +SGI: + +On some SGI systems, you may need to set "AR2= ar -ts" in the Makefile. +If you are using configure, you can do this by saying + ./configure RANLIB='ar -ts' +This change is not needed on all SGIs. Use it only if the make fails at the +stage of linking the completed programs. + +On the MIPS R4000 architecture (Indy, etc.), the compiler option "-mips2" +reportedly speeds up the float DCT method substantially, enough to make it +faster than the default int method (but still slower than the fast int +method). If you use -mips2, you may want to alter the default DCT method to +be float. To do this, put "#define JDCT_DEFAULT JDCT_FLOAT" in jconfig.h. + + +VMS: + +On an Alpha/VMS system with MMS, be sure to use the "/Marco=Alpha=1" +qualifier with MMS when building the JPEG package. + +VAX/VMS v5.5-1 may have problems with the test step of the build procedure +reporting differences when it compares the original and test images. If the +error points to the last block of the files, it is most likely bogus and may +be safely ignored. It seems to be because the files are Stream_LF and +Backup/Compare has difficulty with the (presumably) null padded files. +This problem was not observed on VAX/VMS v6.1 or AXP/VMS v6.1. diff --git a/src/gdcmjpeg/jaricom.c b/src/gdcmjpeg/jaricom.c new file mode 100644 index 00000000..fac05180 --- /dev/null +++ b/src/gdcmjpeg/jaricom.c @@ -0,0 +1,15 @@ +/* + * jaricom.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file holds place for arithmetic entropy codec tables. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + +INT32 jaritab[1]; /* dummy table */ diff --git a/src/gdcmjpeg/jcapimin.c b/src/gdcmjpeg/jcapimin.c new file mode 100644 index 00000000..7bb6e7b4 --- /dev/null +++ b/src/gdcmjpeg/jcapimin.c @@ -0,0 +1,280 @@ +/* + * jcapimin.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains application interface code for the compression half + * of the JPEG library. These are the "minimum" API routines that may be + * needed in either the normal full-compression case or the transcoding-only + * case. + * + * Most of the routines intended to be called directly by an application + * are in this file or in jcapistd.c. But also see jcparam.c for + * parameter-setup helper routines, jcomapi.c for routines shared by + * compression and decompression, and jctrans.c for the transcoding case. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Initialization of a JPEG compression object. + * The error manager must already be set up (in case memory manager fails). + */ + +GLOBAL(void) +jpeg_CreateCompress (j_compress_ptr cinfo, int version, size_t structsize) +{ + int i; + + /* Guard against version mismatches between library and caller. */ + cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */ + if (version != JPEG_LIB_VERSION) + ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version); + if (structsize != SIZEOF(struct jpeg_compress_struct)) + ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, + (int) SIZEOF(struct jpeg_compress_struct), (int) structsize); + + /* For debugging purposes, we zero the whole master structure. + * But the application has already set the err pointer, and may have set + * client_data, so we have to save and restore those fields. + * Note: if application hasn't set client_data, tools like Purify may + * complain here. + */ + { + struct jpeg_error_mgr * err = cinfo->err; + void * client_data = cinfo->client_data; /* ignore Purify complaint here */ + MEMZERO(cinfo, SIZEOF(struct jpeg_compress_struct)); + cinfo->err = err; + cinfo->client_data = client_data; + } + cinfo->is_decompressor = FALSE; + + /* Initialize a memory manager instance for this object */ + jinit_memory_mgr((j_common_ptr) cinfo); + + /* Zero out pointers to permanent structures. */ + cinfo->progress = NULL; + cinfo->dest = NULL; + + cinfo->comp_info = NULL; + + for (i = 0; i < NUM_QUANT_TBLS; i++) + cinfo->quant_tbl_ptrs[i] = NULL; + + for (i = 0; i < NUM_HUFF_TBLS; i++) { + cinfo->dc_huff_tbl_ptrs[i] = NULL; + cinfo->ac_huff_tbl_ptrs[i] = NULL; + } + + cinfo->script_space = NULL; + + cinfo->input_gamma = 1.0; /* in case application forgets */ + + /* OK, I'm ready */ + cinfo->global_state = CSTATE_START; +} + + +/* + * Destruction of a JPEG compression object + */ + +GLOBAL(void) +jpeg_destroy_compress (j_compress_ptr cinfo) +{ + jpeg_destroy((j_common_ptr) cinfo); /* use common routine */ +} + + +/* + * Abort processing of a JPEG compression operation, + * but don't destroy the object itself. + */ + +GLOBAL(void) +jpeg_abort_compress (j_compress_ptr cinfo) +{ + jpeg_abort((j_common_ptr) cinfo); /* use common routine */ +} + + +/* + * Forcibly suppress or un-suppress all quantization and Huffman tables. + * Marks all currently defined tables as already written (if suppress) + * or not written (if !suppress). This will control whether they get emitted + * by a subsequent jpeg_start_compress call. + * + * This routine is exported for use by applications that want to produce + * abbreviated JPEG datastreams. It logically belongs in jcparam.c, but + * since it is called by jpeg_start_compress, we put it here --- otherwise + * jcparam.o would be linked whether the application used it or not. + */ + +GLOBAL(void) +jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress) +{ + int i; + JQUANT_TBL * qtbl; + JHUFF_TBL * htbl; + + for (i = 0; i < NUM_QUANT_TBLS; i++) { + if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL) + qtbl->sent_table = suppress; + } + + for (i = 0; i < NUM_HUFF_TBLS; i++) { + if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL) + htbl->sent_table = suppress; + if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL) + htbl->sent_table = suppress; + } +} + + +/* + * Finish JPEG compression. + * + * If a multipass operating mode was selected, this may do a great deal of + * work including most of the actual output. + */ + +GLOBAL(void) +jpeg_finish_compress (j_compress_ptr cinfo) +{ + JDIMENSION iMCU_row; + + if (cinfo->global_state == CSTATE_SCANNING || + cinfo->global_state == CSTATE_RAW_OK) { + /* Terminate first pass */ + if (cinfo->next_scanline < cinfo->image_height) + ERREXIT(cinfo, JERR_TOO_LITTLE_DATA); + (*cinfo->master->finish_pass) (cinfo); + } else if (cinfo->global_state != CSTATE_WRCOEFS) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + /* Perform any remaining passes */ + while (! cinfo->master->is_last_pass) { + (*cinfo->master->prepare_for_pass) (cinfo); + for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) { + if (cinfo->progress != NULL) { + cinfo->progress->pass_counter = (long) iMCU_row; + cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows; + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + } + /* We bypass the main controller and invoke coef controller directly; + * all work is being done from the coefficient buffer. + */ + if (! (*cinfo->codec->compress_data) (cinfo, (JSAMPIMAGE) NULL)) + ERREXIT(cinfo, JERR_CANT_SUSPEND); + } + (*cinfo->master->finish_pass) (cinfo); + } + /* Write EOI, do final cleanup */ + (*cinfo->marker->write_file_trailer) (cinfo); + (*cinfo->dest->term_destination) (cinfo); + /* We can use jpeg_abort to release memory and reset global_state */ + jpeg_abort((j_common_ptr) cinfo); +} + + +/* + * Write a special marker. + * This is only recommended for writing COM or APPn markers. + * Must be called after jpeg_start_compress() and before + * first call to jpeg_write_scanlines() or jpeg_write_raw_data(). + */ + +GLOBAL(void) +jpeg_write_marker (j_compress_ptr cinfo, int marker, + const JOCTET *dataptr, unsigned int datalen) +{ + JMETHOD(void, write_marker_byte, (j_compress_ptr info, int val)); + + if (cinfo->next_scanline != 0 || + (cinfo->global_state != CSTATE_SCANNING && + cinfo->global_state != CSTATE_RAW_OK && + cinfo->global_state != CSTATE_WRCOEFS)) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + (*cinfo->marker->write_marker_header) (cinfo, marker, datalen); + write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */ + while (datalen--) { + (*write_marker_byte) (cinfo, *dataptr); + dataptr++; + } +} + +/* Same, but piecemeal. */ + +GLOBAL(void) +jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen) +{ + if (cinfo->next_scanline != 0 || + (cinfo->global_state != CSTATE_SCANNING && + cinfo->global_state != CSTATE_RAW_OK && + cinfo->global_state != CSTATE_WRCOEFS)) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + (*cinfo->marker->write_marker_header) (cinfo, marker, datalen); +} + +GLOBAL(void) +jpeg_write_m_byte (j_compress_ptr cinfo, int val) +{ + (*cinfo->marker->write_marker_byte) (cinfo, val); +} + + +/* + * Alternate compression function: just write an abbreviated table file. + * Before calling this, all parameters and a data destination must be set up. + * + * To produce a pair of files containing abbreviated tables and abbreviated + * image data, one would proceed as follows: + * + * initialize JPEG object + * set JPEG parameters + * set destination to table file + * jpeg_write_tables(cinfo); + * set destination to image file + * jpeg_start_compress(cinfo, FALSE); + * write data... + * jpeg_finish_compress(cinfo); + * + * jpeg_write_tables has the side effect of marking all tables written + * (same as jpeg_suppress_tables(..., TRUE)). Thus a subsequent start_compress + * will not re-emit the tables unless it is passed write_all_tables=TRUE. + */ + +GLOBAL(void) +jpeg_write_tables (j_compress_ptr cinfo) +{ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + /* (Re)initialize error mgr and destination modules */ + (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); + (*cinfo->dest->init_destination) (cinfo); + /* Initialize the marker writer ... bit of a crock to do it here. */ + jinit_marker_writer(cinfo); + /* Write them tables! */ + (*cinfo->marker->write_tables_only) (cinfo); + /* And clean up. */ + (*cinfo->dest->term_destination) (cinfo); + /* + * In library releases up through v6a, we called jpeg_abort() here to free + * any working memory allocated by the destination manager and marker + * writer. Some applications had a problem with that: they allocated space + * of their own from the library memory manager, and didn't want it to go + * away during write_tables. So now we do nothing. This will cause a + * memory leak if an app calls write_tables repeatedly without doing a full + * compression cycle or otherwise resetting the JPEG object. However, that + * seems less bad than unexpectedly freeing memory in the normal case. + * An app that prefers the old behavior can call jpeg_abort for itself after + * each call to jpeg_write_tables(). + */ +} diff --git a/src/gdcmjpeg/jcapistd.c b/src/gdcmjpeg/jcapistd.c new file mode 100644 index 00000000..ee2a8496 --- /dev/null +++ b/src/gdcmjpeg/jcapistd.c @@ -0,0 +1,161 @@ +/* + * jcapistd.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains application interface code for the compression half + * of the JPEG library. These are the "standard" API routines that are + * used in the normal full-compression case. They are not used by a + * transcoding-only application. Note that if an application links in + * jpeg_start_compress, it will end up linking in the entire compressor. + * We thus must separate this file from jcapimin.c to avoid linking the + * whole compression library into a transcoder. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Compression initialization. + * Before calling this, all parameters and a data destination must be set up. + * + * We require a write_all_tables parameter as a failsafe check when writing + * multiple datastreams from the same compression object. Since prior runs + * will have left all the tables marked sent_table=TRUE, a subsequent run + * would emit an abbreviated stream (no tables) by default. This may be what + * is wanted, but for safety's sake it should not be the default behavior: + * programmers should have to make a deliberate choice to emit abbreviated + * images. Therefore the documentation and examples should encourage people + * to pass write_all_tables=TRUE; then it will take active thought to do the + * wrong thing. + */ + +GLOBAL(void) +jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables) +{ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + if (write_all_tables) + jpeg_suppress_tables(cinfo, FALSE); /* mark all tables to be written */ + + /* (Re)initialize error mgr and destination modules */ + (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); + (*cinfo->dest->init_destination) (cinfo); + /* Perform master selection of active modules */ + jinit_compress_master(cinfo); + /* Set up for the first pass */ + (*cinfo->master->prepare_for_pass) (cinfo); + /* Ready for application to drive first pass through jpeg_write_scanlines + * or jpeg_write_raw_data. + */ + cinfo->next_scanline = 0; + cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING); +} + + +/* + * Write some scanlines of data to the JPEG compressor. + * + * The return value will be the number of lines actually written. + * This should be less than the supplied num_lines only in case that + * the data destination module has requested suspension of the compressor, + * or if more than image_height scanlines are passed in. + * + * Note: we warn about excess calls to jpeg_write_scanlines() since + * this likely signals an application programmer error. However, + * excess scanlines passed in the last valid call are *silently* ignored, + * so that the application need not adjust num_lines for end-of-image + * when using a multiple-scanline buffer. + */ + +GLOBAL(JDIMENSION) +jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines, + JDIMENSION num_lines) +{ + JDIMENSION row_ctr, rows_left; + + if (cinfo->global_state != CSTATE_SCANNING) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + if (cinfo->next_scanline >= cinfo->image_height) + WARNMS(cinfo, JWRN_TOO_MUCH_DATA); + + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) { + cinfo->progress->pass_counter = (long) cinfo->next_scanline; + cinfo->progress->pass_limit = (long) cinfo->image_height; + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + } + + /* Give master control module another chance if this is first call to + * jpeg_write_scanlines. This lets output of the frame/scan headers be + * delayed so that application can write COM, etc, markers between + * jpeg_start_compress and jpeg_write_scanlines. + */ + if (cinfo->master->call_pass_startup) + (*cinfo->master->pass_startup) (cinfo); + + /* Ignore any extra scanlines at bottom of image. */ + rows_left = cinfo->image_height - cinfo->next_scanline; + if (num_lines > rows_left) + num_lines = rows_left; + + row_ctr = 0; + (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines); + cinfo->next_scanline += row_ctr; + return row_ctr; +} + + +/* + * Alternate entry point to write raw data. + * Processes exactly one iMCU row per call, unless suspended. + */ + +GLOBAL(JDIMENSION) +jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data, + JDIMENSION num_lines) +{ + JDIMENSION lines_per_iMCU_row; + + if (cinfo->global_state != CSTATE_RAW_OK) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + if (cinfo->next_scanline >= cinfo->image_height) { + WARNMS(cinfo, JWRN_TOO_MUCH_DATA); + return 0; + } + + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) { + cinfo->progress->pass_counter = (long) cinfo->next_scanline; + cinfo->progress->pass_limit = (long) cinfo->image_height; + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + } + + /* Give master control module another chance if this is first call to + * jpeg_write_raw_data. This lets output of the frame/scan headers be + * delayed so that application can write COM, etc, markers between + * jpeg_start_compress and jpeg_write_raw_data. + */ + if (cinfo->master->call_pass_startup) + (*cinfo->master->pass_startup) (cinfo); + + /* Verify that at least one iMCU row has been passed. */ + lines_per_iMCU_row = cinfo->max_v_samp_factor * cinfo->data_unit; + if (num_lines < lines_per_iMCU_row) + ERREXIT(cinfo, JERR_BUFFER_SIZE); + + /* Directly compress the row. */ + if (! (*cinfo->codec->compress_data) (cinfo, data)) { + /* If compressor did not consume the whole row, suspend processing. */ + return 0; + } + + /* OK, we processed one iMCU row. */ + cinfo->next_scanline += lines_per_iMCU_row; + return lines_per_iMCU_row; +} diff --git a/src/gdcmjpeg/jcarith.c b/src/gdcmjpeg/jcarith.c new file mode 100644 index 00000000..7a179361 --- /dev/null +++ b/src/gdcmjpeg/jcarith.c @@ -0,0 +1,24 @@ +/* + * jcarith.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file holds place for arithmetic entropy encoding routines. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Module initialization routine for arithmetic entropy encoding. + */ + +GLOBAL(void) +jinit_arith_encoder (j_compress_ptr cinfo) +{ + ERREXIT(cinfo, JERR_ARITH_NOTIMPL); +} diff --git a/src/gdcmjpeg/jccoefct.c b/src/gdcmjpeg/jccoefct.c new file mode 100644 index 00000000..cad73c87 --- /dev/null +++ b/src/gdcmjpeg/jccoefct.c @@ -0,0 +1,455 @@ +/* + * jccoefct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the coefficient buffer controller for compression. + * This controller is the top level of the JPEG compressor proper. + * The coefficient buffer lies between forward-DCT and entropy encoding steps. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ + + +/* We use a full-image coefficient buffer when doing Huffman optimization, + * and also for writing multiple-scan JPEG files. In all cases, the DCT + * step is run during the first pass, and subsequent passes need only read + * the buffered coefficients. + */ +#ifdef ENTROPY_OPT_SUPPORTED +#define FULL_COEF_BUFFER_SUPPORTED +#else +#ifdef C_MULTISCAN_FILES_SUPPORTED +#define FULL_COEF_BUFFER_SUPPORTED +#endif +#endif + + +/* Private buffer controller object */ + +typedef struct { + JDIMENSION iMCU_row_num; /* iMCU row # within image */ + JDIMENSION mcu_ctr; /* counts MCUs processed in current row */ + int MCU_vert_offset; /* counts MCU rows within iMCU row */ + int MCU_rows_per_iMCU_row; /* number of such rows needed */ + + /* For single-pass compression, it's sufficient to buffer just one MCU + * (although this may prove a bit slow in practice). We allocate a + * workspace of C_MAX_DATA_UNITS_IN_MCU coefficient blocks, and reuse it for + * each MCU constructed and sent. (On 80x86, the workspace is FAR even + * though it's not really very big; this is to keep the module interfaces + * unchanged when a large coefficient buffer is necessary.) + * In multi-pass modes, this array points to the current MCU's blocks + * within the virtual arrays. + */ + JBLOCKROW MCU_buffer[C_MAX_DATA_UNITS_IN_MCU]; + + /* In multi-pass modes, we need a virtual block array for each component. */ + jvirt_barray_ptr whole_image[MAX_COMPONENTS]; +} c_coef_controller; + +typedef c_coef_controller * c_coef_ptr; + + +/* Forward declarations */ +METHODDEF(boolean) compress_data + JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); +#ifdef FULL_COEF_BUFFER_SUPPORTED +METHODDEF(boolean) compress_first_pass + JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); +METHODDEF(boolean) compress_output + JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); +#endif + + +LOCAL(void) +start_iMCU_row (j_compress_ptr cinfo) +/* Reset within-iMCU-row counters for a new row */ +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + + /* In an interleaved scan, an MCU row is the same as an iMCU row. + * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows. + * But at the bottom of the image, process only what's left. + */ + if (cinfo->comps_in_scan > 1) { + coef->MCU_rows_per_iMCU_row = 1; + } else { + if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1)) + coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor; + else + coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height; + } + + coef->mcu_ctr = 0; + coef->MCU_vert_offset = 0; +} + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + + coef->iMCU_row_num = 0; + start_iMCU_row(cinfo); + + switch (pass_mode) { + case JBUF_PASS_THRU: + if (coef->whole_image[0] != NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + lossyc->pub.compress_data = compress_data; + break; +#ifdef FULL_COEF_BUFFER_SUPPORTED + case JBUF_SAVE_AND_PASS: + if (coef->whole_image[0] == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + lossyc->pub.compress_data = compress_first_pass; + break; + case JBUF_CRANK_DEST: + if (coef->whole_image[0] == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + lossyc->pub.compress_data = compress_output; + break; +#endif + default: + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + break; + } +} + + +/* + * Process some data in the single-pass case. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor block rows for each component in the image. + * Returns TRUE if the iMCU row is completed, FALSE if suspended. + * + * NB: input_buf contains a plane for each component in image, + * which we index according to the component's SOF position. + */ + +METHODDEF(boolean) +compress_data (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + int blkn, bi, ci, yindex, yoffset, blockcnt; + JDIMENSION ypos, xpos; + jpeg_component_info *compptr; + + /* Loop to write as much as one whole iMCU row */ + for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; + yoffset++) { + for (MCU_col_num = coef->mcu_ctr; MCU_col_num <= last_MCU_col; + MCU_col_num++) { + /* Determine where data comes from in input_buf and do the DCT thing. + * Each call on forward_DCT processes a horizontal row of DCT blocks + * as wide as an MCU; we rely on having allocated the MCU_buffer[] blocks + * sequentially. Dummy blocks at the right or bottom edge are filled in + * specially. The data in them does not matter for image reconstruction, + * so we fill them with values that will encode to the smallest amount of + * data, viz: all zeroes in the AC entries, DC entries equal to previous + * block's DC value. (Thanks to Thomas Kinsman for this idea.) + */ + blkn = 0; + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width + : compptr->last_col_width; + xpos = MCU_col_num * compptr->MCU_sample_width; + ypos = yoffset * DCTSIZE; /* ypos == (yoffset+yindex) * DCTSIZE */ + for (yindex = 0; yindex < compptr->MCU_height; yindex++) { + if (coef->iMCU_row_num < last_iMCU_row || + yoffset+yindex < compptr->last_row_height) { + (*lossyc->fdct_forward_DCT) (cinfo, compptr, + input_buf[compptr->component_index], + coef->MCU_buffer[blkn], + ypos, xpos, (JDIMENSION) blockcnt); + if (blockcnt < compptr->MCU_width) { + /* Create some dummy blocks at the right edge of the image. */ + jzero_far((void FAR *) coef->MCU_buffer[blkn + blockcnt], + (compptr->MCU_width - blockcnt) * SIZEOF(JBLOCK)); + for (bi = blockcnt; bi < compptr->MCU_width; bi++) { + coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn+bi-1][0][0]; + } + } + } else { + /* Create a row of dummy blocks at the bottom of the image. */ + jzero_far((void FAR *) coef->MCU_buffer[blkn], + compptr->MCU_width * SIZEOF(JBLOCK)); + for (bi = 0; bi < compptr->MCU_width; bi++) { + coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn-1][0][0]; + } + } + blkn += compptr->MCU_width; + ypos += DCTSIZE; + } + } + /* Try to write the MCU. In event of a suspension failure, we will + * re-DCT the MCU on restart (a bit inefficient, could be fixed...) + */ + if (! (*lossyc->entropy_encode_mcu) (cinfo, coef->MCU_buffer)) { + /* Suspension forced; update state counters and exit */ + coef->MCU_vert_offset = yoffset; + coef->mcu_ctr = MCU_col_num; + return FALSE; + } + } + /* Completed an MCU row, but perhaps not an iMCU row */ + coef->mcu_ctr = 0; + } + /* Completed the iMCU row, advance counters for next one */ + coef->iMCU_row_num++; + start_iMCU_row(cinfo); + return TRUE; +} + + +#ifdef FULL_COEF_BUFFER_SUPPORTED + +/* + * Process some data in the first pass of a multi-pass case. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor block rows for each component in the image. + * This amount of data is read from the source buffer, DCT'd and quantized, + * and saved into the virtual arrays. We also generate suitable dummy blocks + * as needed at the right and lower edges. (The dummy blocks are constructed + * in the virtual arrays, which have been padded appropriately.) This makes + * it possible for subsequent passes not to worry about real vs. dummy blocks. + * + * We must also emit the data to the entropy encoder. This is conveniently + * done by calling compress_output() after we've loaded the current strip + * of the virtual arrays. + * + * NB: input_buf contains a plane for each component in image. All + * components are DCT'd and loaded into the virtual arrays in this pass. + * However, it may be that only a subset of the components are emitted to + * the entropy encoder during this first pass; be careful about looking + * at the scan-dependent variables (MCU dimensions, etc). + */ + +METHODDEF(boolean) +compress_first_pass (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + JDIMENSION blocks_across, MCUs_across, MCUindex; + int bi, ci, h_samp_factor, block_row, block_rows, ndummy; + JCOEF lastDC; + jpeg_component_info *compptr; + JBLOCKARRAY buffer; + JBLOCKROW thisblockrow, lastblockrow; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Align the virtual buffer for this component. */ + buffer = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[ci], + coef->iMCU_row_num * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, TRUE); + /* Count non-dummy DCT block rows in this iMCU row. */ + if (coef->iMCU_row_num < last_iMCU_row) + block_rows = compptr->v_samp_factor; + else { + /* NB: can't use last_row_height here, since may not be set! */ + block_rows = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (block_rows == 0) block_rows = compptr->v_samp_factor; + } + blocks_across = compptr->width_in_data_units; + h_samp_factor = compptr->h_samp_factor; + /* Count number of dummy blocks to be added at the right margin. */ + ndummy = (int) (blocks_across % h_samp_factor); + if (ndummy > 0) + ndummy = h_samp_factor - ndummy; + /* Perform DCT for all non-dummy blocks in this iMCU row. Each call + * on forward_DCT processes a complete horizontal row of DCT blocks. + */ + for (block_row = 0; block_row < block_rows; block_row++) { + thisblockrow = buffer[block_row]; + (*lossyc->fdct_forward_DCT) (cinfo, compptr, + input_buf[ci], thisblockrow, + (JDIMENSION) (block_row * DCTSIZE), + (JDIMENSION) 0, blocks_across); + if (ndummy > 0) { + /* Create dummy blocks at the right edge of the image. */ + thisblockrow += blocks_across; /* => first dummy block */ + jzero_far((void FAR *) thisblockrow, ndummy * SIZEOF(JBLOCK)); + lastDC = thisblockrow[-1][0]; + for (bi = 0; bi < ndummy; bi++) { + thisblockrow[bi][0] = lastDC; + } + } + } + /* If at end of image, create dummy block rows as needed. + * The tricky part here is that within each MCU, we want the DC values + * of the dummy blocks to match the last real block's DC value. + * This squeezes a few more bytes out of the resulting file... + */ + if (coef->iMCU_row_num == last_iMCU_row) { + blocks_across += ndummy; /* include lower right corner */ + MCUs_across = blocks_across / h_samp_factor; + for (block_row = block_rows; block_row < compptr->v_samp_factor; + block_row++) { + thisblockrow = buffer[block_row]; + lastblockrow = buffer[block_row-1]; + jzero_far((void FAR *) thisblockrow, + (size_t) (blocks_across * SIZEOF(JBLOCK))); + for (MCUindex = 0; MCUindex < MCUs_across; MCUindex++) { + lastDC = lastblockrow[h_samp_factor-1][0]; + for (bi = 0; bi < h_samp_factor; bi++) { + thisblockrow[bi][0] = lastDC; + } + thisblockrow += h_samp_factor; /* advance to next MCU in row */ + lastblockrow += h_samp_factor; + } + } + } + } + /* NB: compress_output will increment iMCU_row_num if successful. + * A suspension return will result in redoing all the work above next time. + */ + + /* Emit data to the entropy encoder, sharing code with subsequent passes */ + return compress_output(cinfo, input_buf); +} + + +/* + * Process some data in subsequent passes of a multi-pass case. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor block rows for each component in the scan. + * The data is obtained from the virtual arrays and fed to the entropy coder. + * Returns TRUE if the iMCU row is completed, FALSE if suspended. + * + * NB: input_buf is ignored; it is likely to be a NULL pointer. + */ + +METHODDEF(boolean) +compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + int blkn, ci, xindex, yindex, yoffset; + JDIMENSION start_col; + JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN]; + JBLOCKROW buffer_ptr; + jpeg_component_info *compptr; + (void)input_buf; + + /* Align the virtual buffers for the components used in this scan. + * NB: during first pass, this is safe only because the buffers will + * already be aligned properly, so jmemmgr.c won't need to do any I/O. + */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + buffer[ci] = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index], + coef->iMCU_row_num * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, FALSE); + } + + /* Loop to process one whole iMCU row */ + for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; + yoffset++) { + for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row; + MCU_col_num++) { + /* Construct list of pointers to DCT blocks belonging to this MCU */ + blkn = 0; /* index of current DCT block within MCU */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + start_col = MCU_col_num * compptr->MCU_width; + for (yindex = 0; yindex < compptr->MCU_height; yindex++) { + buffer_ptr = buffer[ci][yindex+yoffset] + start_col; + for (xindex = 0; xindex < compptr->MCU_width; xindex++) { + coef->MCU_buffer[blkn++] = buffer_ptr++; + } + } + } + /* Try to write the MCU. */ + if (! (*lossyc->entropy_encode_mcu) (cinfo, coef->MCU_buffer)) { + /* Suspension forced; update state counters and exit */ + coef->MCU_vert_offset = yoffset; + coef->mcu_ctr = MCU_col_num; + return FALSE; + } + } + /* Completed an MCU row, but perhaps not an iMCU row */ + coef->mcu_ctr = 0; + } + /* Completed the iMCU row, advance counters for next one */ + coef->iMCU_row_num++; + start_iMCU_row(cinfo); + return TRUE; +} + +#endif /* FULL_COEF_BUFFER_SUPPORTED */ + + +/* + * Initialize coefficient buffer controller. + */ + +GLOBAL(void) +jinit_c_coef_controller (j_compress_ptr cinfo, boolean need_full_buffer) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef; + + coef = (c_coef_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(c_coef_controller)); + lossyc->coef_private = (struct jpeg_c_coef_controller *) coef; + lossyc->coef_start_pass = start_pass_coef; + + /* Create the coefficient buffer. */ + if (need_full_buffer) { +#ifdef FULL_COEF_BUFFER_SUPPORTED + /* Allocate a full-image virtual array for each component, */ + /* padded to a multiple of samp_factor DCT blocks in each direction. */ + int ci; + jpeg_component_info *compptr; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + coef->whole_image[ci] = (*cinfo->mem->request_virt_barray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) jround_up((long) compptr->height_in_data_units, + (long) compptr->v_samp_factor), + (JDIMENSION) compptr->v_samp_factor); + } +#else + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); +#endif + } else { + /* We only need a single-MCU buffer. */ + JBLOCKROW buffer; + int i; + + buffer = (JBLOCKROW) + (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, + C_MAX_DATA_UNITS_IN_MCU * SIZEOF(JBLOCK)); + for (i = 0; i < C_MAX_DATA_UNITS_IN_MCU; i++) { + coef->MCU_buffer[i] = buffer + i; + } + coef->whole_image[0] = NULL; /* flag for no virtual arrays */ + } +} diff --git a/src/gdcmjpeg/jccolor.c b/src/gdcmjpeg/jccolor.c new file mode 100644 index 00000000..a0afd61b --- /dev/null +++ b/src/gdcmjpeg/jccolor.c @@ -0,0 +1,460 @@ +/* + * jccolor.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains input colorspace conversion routines. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Private subobject */ + +typedef struct { + struct jpeg_color_converter pub; /* public fields */ + + /* Private state for RGB->YCC conversion */ + INT32 * rgb_ycc_tab; /* => table for RGB to YCbCr conversion */ +} my_color_converter; + +typedef my_color_converter * my_cconvert_ptr; + + +/**************** RGB -> YCbCr conversion: most common case **************/ + +/* + * YCbCr is defined per CCIR 601-1, except that Cb and Cr are + * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. + * The conversion equations to be implemented are therefore + * Y = 0.29900 * R + 0.58700 * G + 0.11400 * B + * Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B + CENTERJSAMPLE + * Cr = 0.50000 * R - 0.41869 * G - 0.08131 * B + CENTERJSAMPLE + * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.) + * Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2, + * rather than CENTERJSAMPLE, for Cb and Cr. This gave equal positive and + * negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0) + * were not represented exactly. Now we sacrifice exact representation of + * maximum red and maximum blue in order to get exact grayscales. + * + * To avoid floating-point arithmetic, we represent the fractional constants + * as integers scaled up by 2^16 (about 4 digits precision); we have to divide + * the products by 2^16, with appropriate rounding, to get the correct answer. + * + * For even more speed, we avoid doing any multiplications in the inner loop + * by precalculating the constants times R,G,B for all possible values. + * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table); + * for 12-bit samples it is still acceptable. It's not very reasonable for + * 16-bit samples, but if you want lossless storage you shouldn't be changing + * colorspace anyway. + * The CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included + * in the tables to save adding them separately in the inner loop. + */ + +#define SCALEBITS 16 /* speediest right-shift on some machines */ +#define CBCR_OFFSET ((INT32) CENTERJSAMPLE << SCALEBITS) +#define ONE_HALF ((INT32) 1 << (SCALEBITS-1)) +#define FIX(x) ((INT32) ((x) * (1L< Y section */ +#define G_Y_OFF (1*(MAXJSAMPLE+1)) /* offset to G => Y section */ +#define B_Y_OFF (2*(MAXJSAMPLE+1)) /* etc. */ +#define R_CB_OFF (3*(MAXJSAMPLE+1)) +#define G_CB_OFF (4*(MAXJSAMPLE+1)) +#define B_CB_OFF (5*(MAXJSAMPLE+1)) +#define R_CR_OFF B_CB_OFF /* B=>Cb, R=>Cr are the same */ +#define G_CR_OFF (6*(MAXJSAMPLE+1)) +#define B_CR_OFF (7*(MAXJSAMPLE+1)) +#define TABLE_SIZE (8*(MAXJSAMPLE+1)) + + +/* + * Initialize for RGB->YCC colorspace conversion. + */ + +METHODDEF(void) +rgb_ycc_start (j_compress_ptr cinfo) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + INT32 * rgb_ycc_tab; + INT32 i; + + /* Allocate and fill in the conversion tables. */ + cconvert->rgb_ycc_tab = rgb_ycc_tab = (INT32 *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (TABLE_SIZE * SIZEOF(INT32))); + + for (i = 0; i <= MAXJSAMPLE; i++) { + rgb_ycc_tab[i+R_Y_OFF] = FIX(0.29900) * i; + rgb_ycc_tab[i+G_Y_OFF] = FIX(0.58700) * i; + rgb_ycc_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF; + rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.16874)) * i; + rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.33126)) * i; + /* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr. + * This ensures that the maximum output will round to MAXJSAMPLE + * not MAXJSAMPLE+1, and thus that we don't have to range-limit. + */ + rgb_ycc_tab[i+B_CB_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1; +/* B=>Cb and R=>Cr tables are the same + rgb_ycc_tab[i+R_CR_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1; +*/ + rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.41869)) * i; + rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.08131)) * i; + } +} + + +/* + * Convert some rows of samples to the JPEG colorspace. + * + * Note that we change from the application's interleaved-pixel format + * to our internal noninterleaved, one-plane-per-component format. + * The input buffer is therefore three times as wide as the output buffer. + * + * A starting row offset is provided only for the output buffer. The caller + * can easily adjust the passed input_buf value to accommodate any row + * offset required on that side. + */ + +METHODDEF(void) +rgb_ycc_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + register int r, g, b; + register INT32 * ctab = cconvert->rgb_ycc_tab; + register JSAMPROW inptr; + register JSAMPROW outptr0, outptr1, outptr2; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->image_width; + + while (--num_rows >= 0) { + inptr = *input_buf++; + outptr0 = output_buf[0][output_row]; + outptr1 = output_buf[1][output_row]; + outptr2 = output_buf[2][output_row]; + output_row++; + for (col = 0; col < num_cols; col++) { + r = GETJSAMPLE(inptr[RGB_RED]); + g = GETJSAMPLE(inptr[RGB_GREEN]); + b = GETJSAMPLE(inptr[RGB_BLUE]); + inptr += RGB_PIXELSIZE; + /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations + * must be too; we do not need an explicit range-limiting operation. + * Hence the value being shifted is never negative, and we don't + * need the general RIGHT_SHIFT macro. + */ + /* Y */ + outptr0[col] = (JSAMPLE) + ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) + >> SCALEBITS); + /* Cb */ + outptr1[col] = (JSAMPLE) + ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF]) + >> SCALEBITS); + /* Cr */ + outptr2[col] = (JSAMPLE) + ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) + >> SCALEBITS); + } + } +} + + +/**************** Cases other than RGB -> YCbCr **************/ + + +/* + * Convert some rows of samples to the JPEG colorspace. + * This version handles RGB->grayscale conversion, which is the same + * as the RGB->Y portion of RGB->YCbCr. + * We assume rgb_ycc_start has been called (we only use the Y tables). + */ + +METHODDEF(void) +rgb_gray_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + register int r, g, b; + register INT32 * ctab = cconvert->rgb_ycc_tab; + register JSAMPROW inptr; + register JSAMPROW outptr; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->image_width; + + while (--num_rows >= 0) { + inptr = *input_buf++; + outptr = output_buf[0][output_row]; + output_row++; + for (col = 0; col < num_cols; col++) { + r = GETJSAMPLE(inptr[RGB_RED]); + g = GETJSAMPLE(inptr[RGB_GREEN]); + b = GETJSAMPLE(inptr[RGB_BLUE]); + inptr += RGB_PIXELSIZE; + /* Y */ + outptr[col] = (JSAMPLE) + ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) + >> SCALEBITS); + } + } +} + + +/* + * Convert some rows of samples to the JPEG colorspace. + * This version handles Adobe-style CMYK->YCCK conversion, + * where we convert R=1-C, G=1-M, and B=1-Y to YCbCr using the same + * conversion as above, while passing K (black) unchanged. + * We assume rgb_ycc_start has been called. + */ + +METHODDEF(void) +cmyk_ycck_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + register int r, g, b; + register INT32 * ctab = cconvert->rgb_ycc_tab; + register JSAMPROW inptr; + register JSAMPROW outptr0, outptr1, outptr2, outptr3; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->image_width; + + while (--num_rows >= 0) { + inptr = *input_buf++; + outptr0 = output_buf[0][output_row]; + outptr1 = output_buf[1][output_row]; + outptr2 = output_buf[2][output_row]; + outptr3 = output_buf[3][output_row]; + output_row++; + for (col = 0; col < num_cols; col++) { + r = MAXJSAMPLE - GETJSAMPLE(inptr[0]); + g = MAXJSAMPLE - GETJSAMPLE(inptr[1]); + b = MAXJSAMPLE - GETJSAMPLE(inptr[2]); + /* K passes through as-is */ + outptr3[col] = inptr[3]; /* don't need GETJSAMPLE here */ + inptr += 4; + /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations + * must be too; we do not need an explicit range-limiting operation. + * Hence the value being shifted is never negative, and we don't + * need the general RIGHT_SHIFT macro. + */ + /* Y */ + outptr0[col] = (JSAMPLE) + ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) + >> SCALEBITS); + /* Cb */ + outptr1[col] = (JSAMPLE) + ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF]) + >> SCALEBITS); + /* Cr */ + outptr2[col] = (JSAMPLE) + ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) + >> SCALEBITS); + } + } +} + + +/* + * Convert some rows of samples to the JPEG colorspace. + * This version handles grayscale output with no conversion. + * The source can be either plain grayscale or YCbCr (since Y == gray). + */ + +METHODDEF(void) +grayscale_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + register JSAMPROW inptr; + register JSAMPROW outptr; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->image_width; + int instride = cinfo->input_components; + + while (--num_rows >= 0) { + inptr = *input_buf++; + outptr = output_buf[0][output_row]; + output_row++; + for (col = 0; col < num_cols; col++) { + outptr[col] = inptr[0]; /* don't need GETJSAMPLE() here */ + inptr += instride; + } + } +} + + +/* + * Convert some rows of samples to the JPEG colorspace. + * This version handles multi-component colorspaces without conversion. + * We assume input_components == num_components. + */ + +METHODDEF(void) +null_convert (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows) +{ + register JSAMPROW inptr; + register JSAMPROW outptr; + register JDIMENSION col; + register int ci; + int nc = cinfo->num_components; + JDIMENSION num_cols = cinfo->image_width; + + while (--num_rows >= 0) { + /* It seems fastest to make a separate pass for each component. */ + for (ci = 0; ci < nc; ci++) { + inptr = *input_buf; + outptr = output_buf[ci][output_row]; + for (col = 0; col < num_cols; col++) { + outptr[col] = inptr[ci]; /* don't need GETJSAMPLE() here */ + inptr += nc; + } + } + input_buf++; + output_row++; + } +} + + +/* + * Empty method for start_pass. + */ + +METHODDEF(void) +null_method (j_compress_ptr cinfo) +{ + (void)cinfo; + /* no work needed */ +} + + +/* + * Module initialization routine for input colorspace conversion. + */ + +GLOBAL(void) +jinit_color_converter (j_compress_ptr cinfo) +{ + my_cconvert_ptr cconvert; + + cconvert = (my_cconvert_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_color_converter)); + cinfo->cconvert = (struct jpeg_color_converter *) cconvert; + /* set start_pass to null method until we find out differently */ + cconvert->pub.start_pass = null_method; + + /* Make sure input_components agrees with in_color_space */ + switch (cinfo->in_color_space) { + case JCS_GRAYSCALE: + if (cinfo->input_components != 1) + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); + break; + + case JCS_RGB: +#if RGB_PIXELSIZE != 3 + if (cinfo->input_components != RGB_PIXELSIZE) + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); + break; +#endif /* else share code with YCbCr */ + + case JCS_YCbCr: + if (cinfo->input_components != 3) + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); + break; + + case JCS_CMYK: + case JCS_YCCK: + if (cinfo->input_components != 4) + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); + break; + + default: /* JCS_UNKNOWN can be anything */ + if (cinfo->input_components < 1) + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); + break; + } + + /* Check num_components, set conversion method based on requested space */ + switch (cinfo->jpeg_color_space) { + case JCS_GRAYSCALE: + if (cinfo->num_components != 1) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + if (cinfo->in_color_space == JCS_GRAYSCALE) + cconvert->pub.color_convert = grayscale_convert; + else if (cinfo->in_color_space == JCS_RGB) { + cconvert->pub.start_pass = rgb_ycc_start; + cconvert->pub.color_convert = rgb_gray_convert; + } else if (cinfo->in_color_space == JCS_YCbCr) + cconvert->pub.color_convert = grayscale_convert; + else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + case JCS_RGB: + if (cinfo->num_components != 3) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + if (cinfo->in_color_space == JCS_RGB && RGB_PIXELSIZE == 3) + cconvert->pub.color_convert = null_convert; + else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + case JCS_YCbCr: + if (cinfo->num_components != 3) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + if (cinfo->in_color_space == JCS_RGB) { + cconvert->pub.start_pass = rgb_ycc_start; + cconvert->pub.color_convert = rgb_ycc_convert; + } else if (cinfo->in_color_space == JCS_YCbCr) + cconvert->pub.color_convert = null_convert; + else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + case JCS_CMYK: + if (cinfo->num_components != 4) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + if (cinfo->in_color_space == JCS_CMYK) + cconvert->pub.color_convert = null_convert; + else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + case JCS_YCCK: + if (cinfo->num_components != 4) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + if (cinfo->in_color_space == JCS_CMYK) { + cconvert->pub.start_pass = rgb_ycc_start; + cconvert->pub.color_convert = cmyk_ycck_convert; + } else if (cinfo->in_color_space == JCS_YCCK) + cconvert->pub.color_convert = null_convert; + else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + default: /* allow null conversion of JCS_UNKNOWN */ + if (cinfo->jpeg_color_space != cinfo->in_color_space || + cinfo->num_components != cinfo->input_components) + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + cconvert->pub.color_convert = null_convert; + break; + } +} diff --git a/src/gdcmjpeg/jcdctmgr.c b/src/gdcmjpeg/jcdctmgr.c new file mode 100644 index 00000000..5b217990 --- /dev/null +++ b/src/gdcmjpeg/jcdctmgr.c @@ -0,0 +1,390 @@ +/* + * jcdctmgr.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the forward-DCT management logic. + * This code selects a particular DCT implementation to be used, + * and it performs related housekeeping chores including coefficient + * quantization. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ +#include "jdct.h" /* Private declarations for DCT subsystem */ + + +/* Private subobject for this module */ + +typedef struct { + /* Pointer to the DCT routine actually in use */ + forward_DCT_method_ptr do_dct; + + /* The actual post-DCT divisors --- not identical to the quant table + * entries, because of scaling (especially for an unnormalized DCT). + * Each table is given in normal array order. + */ + DCTELEM * divisors[NUM_QUANT_TBLS]; + +#ifdef DCT_FLOAT_SUPPORTED + /* Same as above for the floating-point case. */ + float_DCT_method_ptr do_float_dct; + FAST_FLOAT * float_divisors[NUM_QUANT_TBLS]; +#endif +} fdct_controller; + +typedef fdct_controller * fdct_ptr; + + +/* + * Initialize for a processing pass. + * Verify that all referenced Q-tables are present, and set up + * the divisor table for each one. + * In the current implementation, DCT of all components is done during + * the first pass, even if only some components will be output in the + * first scan. Hence all components should be examined here. + */ + +METHODDEF(void) +start_pass_fdctmgr (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + fdct_ptr fdct = (fdct_ptr) lossyc->fdct_private; + int ci, qtblno, i; + jpeg_component_info *compptr; + JQUANT_TBL * qtbl; + DCTELEM * dtbl; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + qtblno = compptr->quant_tbl_no; + /* Make sure specified quantization table is present */ + if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS || + cinfo->quant_tbl_ptrs[qtblno] == NULL) + ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno); + qtbl = cinfo->quant_tbl_ptrs[qtblno]; + /* Compute divisors for this quant table */ + /* We may do this more than once for same table, but it's not a big deal */ + switch (cinfo->dct_method) { +#ifdef DCT_ISLOW_SUPPORTED + case JDCT_ISLOW: + /* For LL&M IDCT method, divisors are equal to raw quantization + * coefficients multiplied by 8 (to counteract scaling). + */ + if (fdct->divisors[qtblno] == NULL) { + fdct->divisors[qtblno] = (DCTELEM *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + DCTSIZE2 * SIZEOF(DCTELEM)); + } + dtbl = fdct->divisors[qtblno]; + for (i = 0; i < DCTSIZE2; i++) { + dtbl[i] = ((DCTELEM) qtbl->quantval[i]) << 3; + } + break; +#endif +#ifdef DCT_IFAST_SUPPORTED + case JDCT_IFAST: + { + /* For AA&N IDCT method, divisors are equal to quantization + * coefficients scaled by scalefactor[row]*scalefactor[col], where + * scalefactor[0] = 1 + * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7 + * We apply a further scale factor of 8. + */ +#define CONST_BITS 14 + static const INT16 aanscales[DCTSIZE2] = { + /* precomputed values scaled up by 14 bits */ + 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520, + 22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270, + 21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906, + 19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315, + 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520, + 12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552, + 8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446, + 4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247 + }; + SHIFT_TEMPS + + if (fdct->divisors[qtblno] == NULL) { + fdct->divisors[qtblno] = (DCTELEM *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + DCTSIZE2 * SIZEOF(DCTELEM)); + } + dtbl = fdct->divisors[qtblno]; + for (i = 0; i < DCTSIZE2; i++) { + dtbl[i] = (DCTELEM) + DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i], + (INT32) aanscales[i]), + CONST_BITS-3); + } + } + break; +#endif +#ifdef DCT_FLOAT_SUPPORTED + case JDCT_FLOAT: + { + /* For float AA&N IDCT method, divisors are equal to quantization + * coefficients scaled by scalefactor[row]*scalefactor[col], where + * scalefactor[0] = 1 + * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7 + * We apply a further scale factor of 8. + * What's actually stored is 1/divisor so that the inner loop can + * use a multiplication rather than a division. + */ + FAST_FLOAT * fdtbl; + int row, col; + static const double aanscalefactor[DCTSIZE] = { + 1.0, 1.387039845, 1.306562965, 1.175875602, + 1.0, 0.785694958, 0.541196100, 0.275899379 + }; + + if (fdct->float_divisors[qtblno] == NULL) { + fdct->float_divisors[qtblno] = (FAST_FLOAT *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + DCTSIZE2 * SIZEOF(FAST_FLOAT)); + } + fdtbl = fdct->float_divisors[qtblno]; + i = 0; + for (row = 0; row < DCTSIZE; row++) { + for (col = 0; col < DCTSIZE; col++) { + fdtbl[i] = (FAST_FLOAT) + (1.0 / (((double) qtbl->quantval[i] * + aanscalefactor[row] * aanscalefactor[col] * 8.0))); + i++; + } + } + } + break; +#endif + default: + ERREXIT(cinfo, JERR_NOT_COMPILED); + break; + } + } +} + + +/* + * Perform forward DCT on one or more blocks of a component. + * + * The input samples are taken from the sample_data[] array starting at + * position start_row/start_col, and moving to the right for any additional + * blocks. The quantized coefficients are returned in coef_blocks[]. + */ + +METHODDEF(void) +forward_DCT (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY sample_data, JBLOCKROW coef_blocks, + JDIMENSION start_row, JDIMENSION start_col, + JDIMENSION num_blocks) +/* This version is used for integer DCT implementations. */ +{ + /* This routine is heavily used, so it's worth coding it tightly. */ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + fdct_ptr fdct = (fdct_ptr) lossyc->fdct_private; + forward_DCT_method_ptr do_dct = fdct->do_dct; + DCTELEM * divisors = fdct->divisors[compptr->quant_tbl_no]; + DCTELEM workspace[DCTSIZE2]; /* work area for FDCT subroutine */ + JDIMENSION bi; + + sample_data += start_row; /* fold in the vertical offset once */ + + for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) { + /* Load data into workspace, applying unsigned->signed conversion */ + { register DCTELEM *workspaceptr; + register JSAMPROW elemptr; + register int elemr; + + workspaceptr = workspace; + for (elemr = 0; elemr < DCTSIZE; elemr++) { + elemptr = sample_data[elemr] + start_col; +#if DCTSIZE == 8 /* unroll the inner loop */ + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; +#else + { register int elemc; + for (elemc = DCTSIZE; elemc > 0; elemc--) { + *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE; + } + } +#endif + } + } + + /* Perform the DCT */ + (*do_dct) (workspace); + + /* Quantize/descale the coefficients, and store into coef_blocks[] */ + { register DCTELEM temp, qval; + register int i; + register JCOEFPTR output_ptr = coef_blocks[bi]; + + for (i = 0; i < DCTSIZE2; i++) { + qval = divisors[i]; + temp = workspace[i]; + /* Divide the coefficient value by qval, ensuring proper rounding. + * Since C does not specify the direction of rounding for negative + * quotients, we have to force the dividend positive for portability. + * + * In most files, at least half of the output values will be zero + * (at default quantization settings, more like three-quarters...) + * so we should ensure that this case is fast. On many machines, + * a comparison is enough cheaper than a divide to make a special test + * a win. Since both inputs will be nonnegative, we need only test + * for a < b to discover whether a/b is 0. + * If your machine's division is fast enough, define FAST_DIVIDE. + */ +#ifdef FAST_DIVIDE +#define DIVIDE_BY(a,b) a /= b +#else +#define DIVIDE_BY(a,b) if (a >= b) a /= b; else a = 0 +#endif + if (temp < 0) { + temp = -temp; + temp += qval>>1; /* for rounding */ + DIVIDE_BY(temp, qval); + temp = -temp; + } else { + temp += qval>>1; /* for rounding */ + DIVIDE_BY(temp, qval); + } + output_ptr[i] = (JCOEF) temp; + } + } + } +} + + +#ifdef DCT_FLOAT_SUPPORTED + +METHODDEF(void) +forward_DCT_float (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY sample_data, JBLOCKROW coef_blocks, + JDIMENSION start_row, JDIMENSION start_col, + JDIMENSION num_blocks) +/* This version is used for floating-point DCT implementations. */ +{ + /* This routine is heavily used, so it's worth coding it tightly. */ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + fdct_ptr fdct = (fdct_ptr) lossyc->fdct_private; + float_DCT_method_ptr do_dct = fdct->do_float_dct; + FAST_FLOAT * divisors = fdct->float_divisors[compptr->quant_tbl_no]; + FAST_FLOAT workspace[DCTSIZE2]; /* work area for FDCT subroutine */ + JDIMENSION bi; + + sample_data += start_row; /* fold in the vertical offset once */ + + for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) { + /* Load data into workspace, applying unsigned->signed conversion */ + { register FAST_FLOAT *workspaceptr; + register JSAMPROW elemptr; + register int elemr; + + workspaceptr = workspace; + for (elemr = 0; elemr < DCTSIZE; elemr++) { + elemptr = sample_data[elemr] + start_col; +#if DCTSIZE == 8 /* unroll the inner loop */ + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + *workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); +#else + { register int elemc; + for (elemc = DCTSIZE; elemc > 0; elemc--) { + *workspaceptr++ = (FAST_FLOAT) + (GETJSAMPLE(*elemptr++) - CENTERJSAMPLE); + } + } +#endif + } + } + + /* Perform the DCT */ + (*do_dct) (workspace); + + /* Quantize/descale the coefficients, and store into coef_blocks[] */ + { register FAST_FLOAT temp; + register int i; + register JCOEFPTR output_ptr = coef_blocks[bi]; + + for (i = 0; i < DCTSIZE2; i++) { + /* Apply the quantization and scaling factor */ + temp = workspace[i] * divisors[i]; + /* Round to nearest integer. + * Since C does not specify the direction of rounding for negative + * quotients, we have to force the dividend positive for portability. + * The maximum coefficient size is +-16K (for 12-bit data), so this + * code should work for either 16-bit or 32-bit ints. + */ + output_ptr[i] = (JCOEF) ((int) (temp + (FAST_FLOAT) 16384.5) - 16384); + } + } + } +} + +#endif /* DCT_FLOAT_SUPPORTED */ + + +/* + * Initialize FDCT manager. + */ + +GLOBAL(void) +jinit_forward_dct (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + fdct_ptr fdct; + int i; + + fdct = (fdct_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(fdct_controller)); + lossyc->fdct_private = (struct jpeg_forward_dct *) fdct; + lossyc->fdct_start_pass = start_pass_fdctmgr; + + switch (cinfo->dct_method) { +#ifdef DCT_ISLOW_SUPPORTED + case JDCT_ISLOW: + lossyc->fdct_forward_DCT = forward_DCT; + fdct->do_dct = jpeg_fdct_islow; + break; +#endif +#ifdef DCT_IFAST_SUPPORTED + case JDCT_IFAST: + lossyc->fdct_forward_DCT = forward_DCT; + fdct->do_dct = jpeg_fdct_ifast; + break; +#endif +#ifdef DCT_FLOAT_SUPPORTED + case JDCT_FLOAT: + lossyc->fdct_forward_DCT = forward_DCT_float; + fdct->do_float_dct = jpeg_fdct_float; + break; +#endif + default: + ERREXIT(cinfo, JERR_NOT_COMPILED); + break; + } + + /* Mark divisor tables unallocated */ + for (i = 0; i < NUM_QUANT_TBLS; i++) { + fdct->divisors[i] = NULL; +#ifdef DCT_FLOAT_SUPPORTED + fdct->float_divisors[i] = NULL; +#endif + } +} diff --git a/src/gdcmjpeg/jcdiffct.c b/src/gdcmjpeg/jcdiffct.c new file mode 100644 index 00000000..d3953425 --- /dev/null +++ b/src/gdcmjpeg/jcdiffct.c @@ -0,0 +1,410 @@ +/* + * jcdiffct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the difference buffer controller for compression. + * This controller is the top level of the lossless JPEG compressor proper. + * The difference buffer lies between prediction/differencing and entropy + * encoding. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ + + +#ifdef C_LOSSLESS_SUPPORTED + +/* We use a full-image sample buffer when doing Huffman optimization, + * and also for writing multiple-scan JPEG files. In all cases, the + * full-image buffer is filled during the first pass, and the scaling, + * prediction and differencing steps are run during subsequent passes. + */ +#ifdef ENTROPY_OPT_SUPPORTED +#define FULL_SAMP_BUFFER_SUPPORTED +#else +#ifdef C_MULTISCAN_FILES_SUPPORTED +#define FULL_SAMP_BUFFER_SUPPORTED +#endif +#endif + + +/* Private buffer controller object */ + +typedef struct { + JDIMENSION iMCU_row_num; /* iMCU row # within image */ + JDIMENSION mcu_ctr; /* counts MCUs processed in current row */ + int MCU_vert_offset; /* counts MCU rows within iMCU row */ + int MCU_rows_per_iMCU_row; /* number of such rows needed */ + + JSAMPROW cur_row[MAX_COMPONENTS]; /* row of point transformed samples */ + JSAMPROW prev_row[MAX_COMPONENTS]; /* previous row of Pt'd samples */ + JDIFFARRAY diff_buf[MAX_COMPONENTS]; /* iMCU row of differences */ + + /* In multi-pass modes, we need a virtual sample array for each component. */ + jvirt_sarray_ptr whole_image[MAX_COMPONENTS]; +} c_diff_controller; + +typedef c_diff_controller * c_diff_ptr; + + +/* Forward declarations */ +METHODDEF(boolean) compress_data + JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); +#ifdef FULL_SAMP_BUFFER_SUPPORTED +METHODDEF(boolean) compress_first_pass + JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); +METHODDEF(boolean) compress_output + JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf)); +#endif + + +LOCAL(void) +start_iMCU_row (j_compress_ptr cinfo) +/* Reset within-iMCU-row counters for a new row */ +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_diff_ptr diff = (c_diff_ptr) losslsc->diff_private; + + /* In an interleaved scan, an MCU row is the same as an iMCU row. + * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows. + * But at the bottom of the image, process only what's left. + */ + if (cinfo->comps_in_scan > 1) { + diff->MCU_rows_per_iMCU_row = 1; + } else { + if (diff->iMCU_row_num < (cinfo->total_iMCU_rows-1)) + diff->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor; + else + diff->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height; + } + + diff->mcu_ctr = 0; + diff->MCU_vert_offset = 0; +} + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_diff (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_diff_ptr diff = (c_diff_ptr) losslsc->diff_private; + + diff->iMCU_row_num = 0; + start_iMCU_row(cinfo); + + switch (pass_mode) { + case JBUF_PASS_THRU: + if (diff->whole_image[0] != NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + losslsc->pub.compress_data = compress_data; + break; +#ifdef FULL_SAMP_BUFFER_SUPPORTED + case JBUF_SAVE_AND_PASS: + if (diff->whole_image[0] == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + losslsc->pub.compress_data = compress_first_pass; + break; + case JBUF_CRANK_DEST: + if (diff->whole_image[0] == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + losslsc->pub.compress_data = compress_output; + break; +#endif + default: + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + break; + } +} + + +#define SWAP_ROWS(rowa,rowb) {JSAMPROW temp; temp=rowa; rowa=rowb; rowb=temp;} + +/* + * Process some data in the single-pass case. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor rows for each component in the image. + * Returns TRUE if the iMCU row is completed, FALSE if suspended. + * + * NB: input_buf contains a plane for each component in image, + * which we index according to the component's SOF position. + */ + +METHODDEF(boolean) +compress_data (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_diff_ptr diff = (c_diff_ptr) losslsc->diff_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + JDIMENSION MCU_count; /* number of MCUs encoded */ + /* JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1; */ + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + int comp, ci, yoffset, samp_row, samp_rows, samps_across; + jpeg_component_info *compptr; + + /* Loop to write as much as one whole iMCU row */ + for (yoffset = diff->MCU_vert_offset; yoffset < diff->MCU_rows_per_iMCU_row; + yoffset++) { + + MCU_col_num = diff->mcu_ctr; + + /* Scale and predict each scanline of the MCU-row separately. + * + * Note: We only do this if we are at the start of a MCU-row, ie, + * we don't want to reprocess a row suspended by the output. + */ + if (MCU_col_num == 0) { + for (comp = 0; comp < cinfo->comps_in_scan; comp++) { + compptr = cinfo->cur_comp_info[comp]; + ci = compptr->component_index; + if (diff->iMCU_row_num < last_iMCU_row) + samp_rows = compptr->v_samp_factor; + else { + /* NB: can't use last_row_height here, since may not be set! */ + samp_rows = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (samp_rows == 0) samp_rows = compptr->v_samp_factor; + else { + /* Fill dummy difference rows at the bottom edge with zeros, which + * will encode to the smallest amount of data. + */ + for (samp_row = samp_rows; samp_row < compptr->v_samp_factor; + samp_row++) + MEMZERO(diff->diff_buf[ci][samp_row], + jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor) * SIZEOF(JDIFF)); + } + } + samps_across = compptr->width_in_data_units; + + for (samp_row = 0; samp_row < samp_rows; samp_row++) { + (*losslsc->scaler_scale) (cinfo, + input_buf[ci][samp_row], + diff->cur_row[ci], samps_across); + (*losslsc->predict_difference[ci]) (cinfo, ci, + diff->cur_row[ci], + diff->prev_row[ci], + diff->diff_buf[ci][samp_row], + samps_across); + SWAP_ROWS(diff->cur_row[ci], diff->prev_row[ci]); + } + } + } + + /* Try to write the MCU-row (or remaining portion of suspended MCU-row). */ + MCU_count = + (*losslsc->entropy_encode_mcus) (cinfo, + diff->diff_buf, yoffset, MCU_col_num, + cinfo->MCUs_per_row - MCU_col_num); + if (MCU_count != cinfo->MCUs_per_row - MCU_col_num) { + /* Suspension forced; update state counters and exit */ + diff->MCU_vert_offset = yoffset; + diff->mcu_ctr += MCU_col_num; + return FALSE; + } + + /* Completed an MCU row, but perhaps not an iMCU row */ + diff->mcu_ctr = 0; + } + + /* Completed the iMCU row, advance counters for next one */ + diff->iMCU_row_num++; + start_iMCU_row(cinfo); + return TRUE; +} + + +#ifdef FULL_SAMP_BUFFER_SUPPORTED + +/* + * Process some data in the first pass of a multi-pass case. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor rows for each component in the image. + * This amount of data is read from the source buffer and saved into the + * virtual arrays. + * + * We must also emit the data to the compressor. This is conveniently + * done by calling compress_output() after we've loaded the current strip + * of the virtual arrays. + * + * NB: input_buf contains a plane for each component in image. All components + * are loaded into the virtual arrays in this pass. However, it may be that + * only a subset of the components are emitted to the compressor during + * this first pass; be careful about looking at the scan-dependent variables + * (MCU dimensions, etc). + */ + +METHODDEF(boolean) +compress_first_pass (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_diff_ptr diff = (c_diff_ptr) losslsc->diff_private; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + JDIMENSION samps_across; + int ci, samp_row, samp_rows; + JSAMPARRAY buffer[MAX_COMPONENTS]; + jpeg_component_info *compptr; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Align the virtual buffers for this component. */ + buffer[ci] = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, diff->whole_image[ci], + diff->iMCU_row_num * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, TRUE); + + /* Count non-dummy sample rows in this iMCU row. */ + if (diff->iMCU_row_num < last_iMCU_row) + samp_rows = compptr->v_samp_factor; + else { + /* NB: can't use last_row_height here, since may not be set! */ + samp_rows = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (samp_rows == 0) samp_rows = compptr->v_samp_factor; + } + samps_across = compptr->width_in_data_units; + + /* Perform point transform scaling and prediction/differencing for all + * non-dummy rows in this iMCU row. Each call on these functions + * process a complete row of samples. + */ + for (samp_row = 0; samp_row < samp_rows; samp_row++) { + MEMCOPY(buffer[ci][samp_row], input_buf[ci][samp_row], + samps_across * SIZEOF(JSAMPLE)); + } + } + + /* NB: compress_output will increment iMCU_row_num if successful. + * A suspension return will result in redoing all the work above next time. + */ + + /* Emit data to the compressor, sharing code with subsequent passes */ + return compress_output(cinfo, input_buf); +} + + +/* + * Process some data in subsequent passes of a multi-pass case. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor rows for each component in the scan. + * The data is obtained from the virtual arrays and fed to the compressor. + * Returns TRUE if the iMCU row is completed, FALSE if suspended. + * + * NB: input_buf is ignored; it is likely to be a NULL pointer. + */ + +METHODDEF(boolean) +compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_diff_ptr diff = (c_diff_ptr) losslsc->diff_private; + /* JDIMENSION MCU_col_num; */ /* index of current MCU within row */ + /* JDIMENSION MCU_count; */ /* number of MCUs encoded */ + int comp, ci /* , yoffset */ ; + JSAMPARRAY buffer[MAX_COMPONENTS]; + jpeg_component_info *compptr; + (void)input_buf; + + /* Align the virtual buffers for the components used in this scan. + * NB: during first pass, this is safe only because the buffers will + * already be aligned properly, so jmemmgr.c won't need to do any I/O. + */ + for (comp = 0; comp < cinfo->comps_in_scan; comp++) { + compptr = cinfo->cur_comp_info[comp]; + ci = compptr->component_index; + buffer[ci] = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, diff->whole_image[ci], + diff->iMCU_row_num * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, FALSE); + } + + return compress_data(cinfo, buffer); +} + +#endif /* FULL_SAMP_BUFFER_SUPPORTED */ + + +/* + * Initialize difference buffer controller. + */ + +GLOBAL(void) +jinit_c_diff_controller (j_compress_ptr cinfo, boolean need_full_buffer) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_diff_ptr diff; + int ci, row; + jpeg_component_info *compptr; + + diff = (c_diff_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(c_diff_controller)); + losslsc->diff_private = (void *) diff; + losslsc->diff_start_pass = start_pass_diff; + + /* Create the prediction row buffers. */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + diff->cur_row[ci] = *(*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) 1); + diff->prev_row[ci] = *(*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) 1); + } + + /* Create the difference buffer. */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + diff->diff_buf[ci] = (*cinfo->mem->alloc_darray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) compptr->v_samp_factor); + /* Prefill difference rows with zeros. We do this because only actual + * data is placed in the buffers during prediction/differencing, leaving + * any dummy differences at the right edge as zeros, which will encode + * to the smallest amount of data. + */ + for (row = 0; row < compptr->v_samp_factor; row++) + MEMZERO(diff->diff_buf[ci][row], + jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor) * SIZEOF(JDIFF)); + } + + /* Create the sample buffer. */ + if (need_full_buffer) { +#ifdef FULL_SAMP_BUFFER_SUPPORTED + /* Allocate a full-image virtual array for each component, */ + /* padded to a multiple of samp_factor differences in each direction. */ + int ci; + jpeg_component_info *compptr; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + diff->whole_image[ci] = (*cinfo->mem->request_virt_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) jround_up((long) compptr->height_in_data_units, + (long) compptr->v_samp_factor), + (JDIMENSION) compptr->v_samp_factor); + } +#else + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); +#endif + } else + diff->whole_image[0] = NULL; /* flag for no virtual arrays */ +} + +#endif /* C_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jchuff.c b/src/gdcmjpeg/jchuff.c new file mode 100644 index 00000000..86683b14 --- /dev/null +++ b/src/gdcmjpeg/jchuff.c @@ -0,0 +1,274 @@ +/* + * jchuff.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy decoding routines which are shared + * by the sequential, progressive and lossless decoders. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jchuff.h" /* Declarations shared with jc*huff.c */ + + +/* + * Compute the derived values for a Huffman table. + * This routine also performs some validation checks on the table. + */ + +GLOBAL(void) +jpeg_make_c_derived_tbl (j_compress_ptr cinfo, boolean isDC, int tblno, + c_derived_tbl ** pdtbl) +{ + JHUFF_TBL *htbl; + c_derived_tbl *dtbl; + int p, i, l, lastp, si, maxsymbol; + char huffsize[257]; + unsigned int huffcode[257]; + unsigned int code; + + /* Note that huffsize[] and huffcode[] are filled in code-length order, + * paralleling the order of the symbols themselves in htbl->huffval[]. + */ + + /* Find the input Huffman table */ + if (tblno < 0 || tblno >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno); + htbl = + isDC ? cinfo->dc_huff_tbl_ptrs[tblno] : cinfo->ac_huff_tbl_ptrs[tblno]; + if (htbl == NULL) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno); + + /* Allocate a workspace if we haven't already done so. */ + if (*pdtbl == NULL) + *pdtbl = (c_derived_tbl *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(c_derived_tbl)); + dtbl = *pdtbl; + + /* Figure C.1: make table of Huffman code length for each symbol */ + + p = 0; + for (l = 1; l <= 16; l++) { + i = (int) htbl->bits[l]; + if (i < 0 || p + i > 256) /* protect against table overrun */ + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + while (i--) + huffsize[p++] = (char) l; + } + huffsize[p] = 0; + lastp = p; + + /* Figure C.2: generate the codes themselves */ + /* We also validate that the counts represent a legal Huffman code tree. */ + + code = 0; + si = huffsize[0]; + p = 0; + while (huffsize[p]) { + while (((int) huffsize[p]) == si) { + huffcode[p++] = code; + code++; + } + /* code is now 1 more than the last code used for codelength si; but + * it must still fit in si bits, since no code is allowed to be all ones. + * BUG FIX 2001-09-03: Comparison must be >, not >= + */ + if (((INT32) code) > (((INT32) 1) << si)) + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + code <<= 1; + si++; + } + + /* Figure C.3: generate encoding tables */ + /* These are code and size indexed by symbol value */ + + /* Set all codeless symbols to have code length 0; + * this lets us detect duplicate VAL entries here, and later + * allows emit_bits to detect any attempt to emit such symbols. + */ + MEMZERO(dtbl->ehufsi, SIZEOF(dtbl->ehufsi)); + + /* This is also a convenient place to check for out-of-range + * and duplicated VAL entries. We allow 0..255 for AC symbols + * but only 0..16 for DC. (We could constrain them further + * based on data depth and mode, but this seems enough.) + */ + maxsymbol = isDC ? 16 : 255; + + for (p = 0; p < lastp; p++) { + i = htbl->huffval[p]; + if (i < 0 || i > maxsymbol || dtbl->ehufsi[i]) + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + dtbl->ehufco[i] = huffcode[p]; + dtbl->ehufsi[i] = huffsize[p]; + } +} + + +/* + * Generate the best Huffman code table for the given counts, fill htbl. + * + * The JPEG standard requires that no symbol be assigned a codeword of all + * one bits (so that padding bits added at the end of a compressed segment + * can't look like a valid code). Because of the canonical ordering of + * codewords, this just means that there must be an unused slot in the + * longest codeword length category. Section K.2 of the JPEG spec suggests + * reserving such a slot by pretending that symbol 256 is a valid symbol + * with count 1. In theory that's not optimal; giving it count zero but + * including it in the symbol set anyway should give a better Huffman code. + * But the theoretically better code actually seems to come out worse in + * practice, because it produces more all-ones bytes (which incur stuffed + * zero bytes in the final file). In any case the difference is tiny. + * + * The JPEG standard requires Huffman codes to be no more than 16 bits long. + * If some symbols have a very small but nonzero probability, the Huffman tree + * must be adjusted to meet the code length restriction. We currently use + * the adjustment method suggested in JPEG section K.2. This method is *not* + * optimal; it may not choose the best possible limited-length code. But + * typically only very-low-frequency symbols will be given less-than-optimal + * lengths, so the code is almost optimal. Experimental comparisons against + * an optimal limited-length-code algorithm indicate that the difference is + * microscopic --- usually less than a hundredth of a percent of total size. + * So the extra complexity of an optimal algorithm doesn't seem worthwhile. + */ + +GLOBAL(void) +jpeg_gen_optimal_table (j_compress_ptr cinfo, JHUFF_TBL * htbl, long freq[]) +{ +#define MAX_CLEN 32 /* assumed maximum initial code length */ + UINT8 bits[MAX_CLEN+1]; /* bits[k] = # of symbols with code length k */ + int codesize[257]; /* codesize[k] = code length of symbol k */ + int others[257]; /* next symbol in current branch of tree */ + int c1, c2; + int p, i, j; + long v; + + /* This algorithm is explained in section K.2 of the JPEG standard */ + + MEMZERO(bits, SIZEOF(bits)); + MEMZERO(codesize, SIZEOF(codesize)); + for (i = 0; i < 257; i++) + others[i] = -1; /* init links to empty */ + + freq[256] = 1; /* make sure 256 has a nonzero count */ + /* Including the pseudo-symbol 256 in the Huffman procedure guarantees + * that no real symbol is given code-value of all ones, because 256 + * will be placed last in the largest codeword category. + */ + + /* Huffman's basic algorithm to assign optimal code lengths to symbols */ + + for (;;) { + /* Find the smallest nonzero frequency, set c1 = its symbol */ + /* In case of ties, take the larger symbol number */ + c1 = -1; + v = 1000000000L; + for (i = 0; i <= 256; i++) { + if (freq[i] && freq[i] <= v) { + v = freq[i]; + c1 = i; + } + } + + /* Find the next smallest nonzero frequency, set c2 = its symbol */ + /* In case of ties, take the larger symbol number */ + c2 = -1; + v = 1000000000L; + for (i = 0; i <= 256; i++) { + if (freq[i] && freq[i] <= v && i != c1) { + v = freq[i]; + c2 = i; + } + } + + /* Done if we've merged everything into one frequency */ + if (c2 < 0) + break; + + /* Else merge the two counts/trees */ + freq[c1] += freq[c2]; + freq[c2] = 0; + + /* Increment the codesize of everything in c1's tree branch */ + codesize[c1]++; + while (others[c1] >= 0) { + c1 = others[c1]; + codesize[c1]++; + } + + others[c1] = c2; /* chain c2 onto c1's tree branch */ + + /* Increment the codesize of everything in c2's tree branch */ + codesize[c2]++; + while (others[c2] >= 0) { + c2 = others[c2]; + codesize[c2]++; + } + } + + /* Now count the number of symbols of each code length */ + for (i = 0; i <= 256; i++) { + if (codesize[i]) { + /* The JPEG standard seems to think that this can't happen, */ + /* but I'm paranoid... */ + if (codesize[i] > MAX_CLEN) + ERREXIT(cinfo, JERR_HUFF_CLEN_OVERFLOW); + + bits[codesize[i]]++; + } + } + + /* JPEG doesn't allow symbols with code lengths over 16 bits, so if the pure + * Huffman procedure assigned any such lengths, we must adjust the coding. + * Here is what the JPEG spec says about how this next bit works: + * Since symbols are paired for the longest Huffman code, the symbols are + * removed from this length category two at a time. The prefix for the pair + * (which is one bit shorter) is allocated to one of the pair; then, + * skipping the BITS entry for that prefix length, a code word from the next + * shortest nonzero BITS entry is converted into a prefix for two code words + * one bit longer. + */ + + for (i = MAX_CLEN; i > 16; i--) { + while (bits[i] > 0) { + j = i - 2; /* find length of new prefix to be used */ + while (bits[j] == 0) + j--; + + bits[i] -= 2; /* remove two symbols */ + bits[i-1]++; /* one goes in this length */ + bits[j+1] += 2; /* two new symbols in this length */ + bits[j]--; /* symbol of this length is now a prefix */ + } + } + + /* Remove the count for the pseudo-symbol 256 from the largest codelength */ + while (bits[i] == 0) /* find largest codelength still in use */ + i--; + bits[i]--; + + /* Return final symbol counts (only for lengths 0..16) */ + MEMCOPY(htbl->bits, bits, SIZEOF(htbl->bits)); + + /* Return a list of the symbols sorted by code length */ + /* It's not real clear to me why we don't need to consider the codelength + * changes made above, but the JPEG spec seems to think this works. + */ + p = 0; + for (i = 1; i <= MAX_CLEN; i++) { + for (j = 0; j <= 255; j++) { + if (codesize[j] == i) { + htbl->huffval[p] = (UINT8) j; + p++; + } + } + } + + /* Set sent_table FALSE so updated table will be written to JPEG file. */ + htbl->sent_table = FALSE; +} diff --git a/src/gdcmjpeg/jchuff.h b/src/gdcmjpeg/jchuff.h new file mode 100644 index 00000000..6b0570ea --- /dev/null +++ b/src/gdcmjpeg/jchuff.h @@ -0,0 +1,54 @@ +/* + * jchuff.h + * + * Copyright (C) 1991-1997, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains declarations for Huffman entropy encoding routines + * that are shared between the sequential encoder (jchuff.c) and the + * progressive encoder (jcphuff.c). No other modules need to see these. + */ + +/* The legal range of a DCT coefficient is + * -1024 .. +1023 for 8-bit data; + * -16384 .. +16383 for 12-bit data. + * Hence the magnitude should always fit in 10 or 14 bits respectively. + */ + +#if BITS_IN_JSAMPLE == 8 +#define MAX_COEF_BITS 10 +#else +#define MAX_COEF_BITS 14 +#endif + +/* The legal range of a spatial difference is + * -32767 .. +32768. + * Hence the magnitude should always fit in 16 bits. + */ + +#define MAX_DIFF_BITS 16 + +/* Derived data constructed for each Huffman table */ + +typedef struct { + unsigned int ehufco[256]; /* code for each symbol */ + char ehufsi[256]; /* length of code for each symbol */ + /* If no code has been allocated for a symbol S, ehufsi[S] contains 0 */ +} c_derived_tbl; + +/* Short forms of external names for systems with brain-damaged linkers. */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jpeg_make_c_derived_tbl jMkCDerived +#define jpeg_gen_optimal_table jGenOptTbl +#endif /* NEED_SHORT_EXTERNAL_NAMES */ + +/* Expand a Huffman table definition into the derived format */ +EXTERN(void) jpeg_make_c_derived_tbl + JPP((j_compress_ptr cinfo, boolean isDC, int tblno, + c_derived_tbl ** pdtbl)); + +/* Generate an optimal table definition given the specified counts */ +EXTERN(void) jpeg_gen_optimal_table + JPP((j_compress_ptr cinfo, JHUFF_TBL * htbl, long freq[])); diff --git a/src/gdcmjpeg/jcinit.c b/src/gdcmjpeg/jcinit.c new file mode 100644 index 00000000..b485a8e7 --- /dev/null +++ b/src/gdcmjpeg/jcinit.c @@ -0,0 +1,57 @@ +/* + * jcinit.c + * + * Copyright (C) 1991-1997, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains initialization logic for the JPEG compressor. + * This routine is in charge of selecting the modules to be executed and + * making an initialization call to each one. + * + * Logically, this code belongs in jcmaster.c. It's split out because + * linking this routine implies linking the entire compression library. + * For a transcoding-only application, we want to be able to use jcmaster.c + * without linking in the whole library. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Master selection of compression modules. + * This is done once at the start of processing an image. We determine + * which modules will be used and give them appropriate initialization calls. + */ + +GLOBAL(void) +jinit_compress_master (j_compress_ptr cinfo) +{ + /* Initialize master control (includes parameter checking/processing) */ + jinit_c_master_control(cinfo, FALSE /* full compression */); + + /* Initialize compression codec */ + jinit_c_codec(cinfo); + + /* Preprocessing */ + if (! cinfo->raw_data_in) { + jinit_color_converter(cinfo); + jinit_downsampler(cinfo); + jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */); + } + + jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */); + + jinit_marker_writer(cinfo); + + /* We can now tell the memory manager to allocate virtual arrays. */ + (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo); + + /* Write the datastream header (SOI) immediately. + * Frame and scan headers are postponed till later. + * This lets application insert special markers after the SOI. + */ + (*cinfo->marker->write_file_header) (cinfo); +} diff --git a/src/gdcmjpeg/jclhuff.c b/src/gdcmjpeg/jclhuff.c new file mode 100644 index 00000000..a553ccee --- /dev/null +++ b/src/gdcmjpeg/jclhuff.c @@ -0,0 +1,602 @@ +/* + * jclhuff.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy encoding routines for lossless JPEG. + * + * Much of the complexity here has to do with supporting output suspension. + * If the data destination module demands suspension, we want to be able to + * back up to the start of the current MCU. To do this, we copy state + * variables into local working storage, and update them back to the + * permanent JPEG objects only upon successful completion of an MCU. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ +#include "jchuff.h" /* Declarations shared with jc*huff.c */ + + +/* Expanded entropy encoder object for Huffman encoding. + * + * The savable_state subrecord contains fields that change within an MCU, + * but must not be updated permanently until we complete the MCU. + */ + +typedef struct { + INT32 put_buffer; /* current bit-accumulation buffer */ + int put_bits; /* # of bits now in it */ +} savable_state; + +/* This macro is to work around compilers with missing or broken + * structure assignment. You'll need to fix this code if you have + * such a compiler and you change MAX_COMPS_IN_SCAN. + */ + +#ifndef NO_STRUCT_ASSIGN +#define ASSIGN_STATE(dest,src) ((dest) = (src)) +#else +#define ASSIGN_STATE(dest,src) \ + ((dest).put_buffer = (src).put_buffer, \ + (dest).put_bits = (src).put_bits) +#endif + + +typedef struct { + int ci, yoffset, MCU_width; +} lhe_input_ptr_info; + + +typedef struct { + savable_state saved; /* Bit buffer at start of MCU */ + + /* These fields are NOT loaded into local working state. */ + unsigned int restarts_to_go; /* MCUs left in this restart interval */ + int next_restart_num; /* next restart number to write (0-7) */ + + /* Pointers to derived tables (these workspaces have image lifespan) */ + c_derived_tbl * derived_tbls[NUM_HUFF_TBLS]; + + /* Pointers to derived tables to be used for each data unit within an MCU */ + c_derived_tbl * cur_tbls[C_MAX_DATA_UNITS_IN_MCU]; + +#ifdef ENTROPY_OPT_SUPPORTED /* Statistics tables for optimization */ + long * count_ptrs[NUM_HUFF_TBLS]; + + /* Pointers to stats tables to be used for each data unit within an MCU */ + long * cur_counts[C_MAX_DATA_UNITS_IN_MCU]; +#endif + + /* Pointers to the proper input difference row for each group of data units + * within an MCU. For each component, there are Vi groups of Hi data units. + */ + JDIFFROW input_ptr[C_MAX_DATA_UNITS_IN_MCU]; + + /* Number of input pointers in use for the current MCU. This is the sum + * of all Vi in the MCU. + */ + int num_input_ptrs; + + /* Information used for positioning the input pointers within the input + * difference rows. + */ + lhe_input_ptr_info input_ptr_info[C_MAX_DATA_UNITS_IN_MCU]; + + /* Index of the proper input pointer for each data unit within an MCU */ + int input_ptr_index[C_MAX_DATA_UNITS_IN_MCU]; + +} lhuff_entropy_encoder; + +typedef lhuff_entropy_encoder * lhuff_entropy_ptr; + +/* Working state while writing an MCU. + * This struct contains all the fields that are needed by subroutines. + */ + +typedef struct { + JOCTET * next_output_byte; /* => next byte to write in buffer */ + size_t free_in_buffer; /* # of byte spaces remaining in buffer */ + savable_state cur; /* Current bit buffer & DC state */ + j_compress_ptr cinfo; /* dump_buffer needs access to this */ +} working_state; + + +/* Forward declarations */ +METHODDEF(JDIMENSION) encode_mcus_huff (j_compress_ptr cinfo, + JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, + JDIMENSION MCU_col_num, + JDIMENSION nMCU); +METHODDEF(void) finish_pass_huff JPP((j_compress_ptr cinfo)); +#ifdef ENTROPY_OPT_SUPPORTED +METHODDEF(JDIMENSION) encode_mcus_gather (j_compress_ptr cinfo, + JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, + JDIMENSION MCU_col_num, + JDIMENSION nMCU); +METHODDEF(void) finish_pass_gather JPP((j_compress_ptr cinfo)); +#endif + + +/* + * Initialize for a Huffman-compressed scan. + * If gather_statistics is TRUE, we do not output anything during the scan, + * just count the Huffman symbols used and generate Huffman code tables. + */ + +METHODDEF(void) +start_pass_huff (j_compress_ptr cinfo, boolean gather_statistics) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsc->entropy_private; + int ci, dctbl, sampn, ptrn, yoffset, xoffset; + jpeg_component_info * compptr; + + if (gather_statistics) { +#ifdef ENTROPY_OPT_SUPPORTED + losslsc->entropy_encode_mcus = encode_mcus_gather; + losslsc->pub.entropy_finish_pass = finish_pass_gather; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + losslsc->entropy_encode_mcus = encode_mcus_huff; + losslsc->pub.entropy_finish_pass = finish_pass_huff; + } + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + dctbl = compptr->dc_tbl_no; + if (gather_statistics) { +#ifdef ENTROPY_OPT_SUPPORTED + /* Check for invalid table indexes */ + /* (make_c_derived_tbl does this in the other path) */ + if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl); + /* Allocate and zero the statistics tables */ + /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */ + if (entropy->count_ptrs[dctbl] == NULL) + entropy->count_ptrs[dctbl] = (long *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + 257 * SIZEOF(long)); + MEMZERO(entropy->count_ptrs[dctbl], 257 * SIZEOF(long)); +#endif + } else { + /* Compute derived values for Huffman tables */ + /* We may do this more than once for a table, but it's not expensive */ + jpeg_make_c_derived_tbl(cinfo, TRUE, dctbl, + & entropy->derived_tbls[dctbl]); + } + } + + /* Precalculate encoding info for each sample in an MCU of this scan */ + for (sampn = 0, ptrn = 0; sampn < cinfo->data_units_in_MCU;) { + compptr = cinfo->cur_comp_info[cinfo->MCU_membership[sampn]]; + ci = compptr->component_index; + /* ci = cinfo->MCU_membership[sampn]; + compptr = cinfo->cur_comp_info[ci];*/ + for (yoffset = 0; yoffset < compptr->MCU_height; yoffset++, ptrn++) { + /* Precalculate the setup info for each input pointer */ + entropy->input_ptr_info[ptrn].ci = ci; + entropy->input_ptr_info[ptrn].yoffset = yoffset; + entropy->input_ptr_info[ptrn].MCU_width = compptr->MCU_width; + for (xoffset = 0; xoffset < compptr->MCU_width; xoffset++, sampn++) { + /* Precalculate the input pointer index for each sample */ + entropy->input_ptr_index[sampn] = ptrn; + /* Precalculate which tables to use for each sample */ + entropy->cur_tbls[sampn] = entropy->derived_tbls[compptr->dc_tbl_no]; + entropy->cur_counts[sampn] = entropy->count_ptrs[compptr->dc_tbl_no]; + } + } + } + entropy->num_input_ptrs = ptrn; + + /* Initialize bit buffer to empty */ + entropy->saved.put_buffer = 0; + entropy->saved.put_bits = 0; + + /* Initialize restart stuff */ + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num = 0; +} + + +/* Outputting bytes to the file */ + +/* Emit a byte, taking 'action' if must suspend. */ +#define emit_byte(state,val,action) \ + { *(state)->next_output_byte++ = (JOCTET) (val); \ + if (--(state)->free_in_buffer == 0) \ + if (! dump_buffer(state)) \ + { action; } } + + +LOCAL(boolean) +dump_buffer (working_state * state) +/* Empty the output buffer; return TRUE if successful, FALSE if must suspend */ +{ + struct jpeg_destination_mgr * dest = state->cinfo->dest; + + if (! (*dest->empty_output_buffer) (state->cinfo)) + return FALSE; + /* After a successful buffer dump, must reset buffer pointers */ + state->next_output_byte = dest->next_output_byte; + state->free_in_buffer = dest->free_in_buffer; + return TRUE; +} + + +/* Outputting bits to the file */ + +/* Only the right 24 bits of put_buffer are used; the valid bits are + * left-justified in this part. At most 16 bits can be passed to emit_bits + * in one call, and we never retain more than 7 bits in put_buffer + * between calls, so 24 bits are sufficient. + */ + +INLINE +LOCAL(boolean) +emit_bits (working_state * state, unsigned int code, int size) +/* Emit some bits; return TRUE if successful, FALSE if must suspend */ +{ + /* This routine is heavily used, so it's worth coding tightly. */ + register INT32 put_buffer = (INT32) code; + register int put_bits = state->cur.put_bits; + + /* if size is 0, caller used an invalid Huffman table entry */ + if (size == 0) + ERREXIT(state->cinfo, JERR_HUFF_MISSING_CODE); + + put_buffer &= (((INT32) 1)<cur.put_buffer; /* and merge with old buffer contents */ + + while (put_bits >= 8) { + int c = (int) ((put_buffer >> 16) & 0xFF); + + emit_byte(state, c, return FALSE); + if (c == 0xFF) { /* need to stuff a zero byte? */ + emit_byte(state, 0, return FALSE); + } + put_buffer <<= 8; + put_bits -= 8; + } + + state->cur.put_buffer = put_buffer; /* update state variables */ + state->cur.put_bits = put_bits; + + return TRUE; +} + + +LOCAL(boolean) +flush_bits (working_state * state) +{ + if (! emit_bits(state, 0x7F, 7)) /* fill any partial byte with ones */ + return FALSE; + state->cur.put_buffer = 0; /* and reset bit-buffer to empty */ + state->cur.put_bits = 0; + return TRUE; +} + + +/* + * Emit a restart marker & resynchronize predictions. + */ + +LOCAL(boolean) +emit_restart (working_state * state, int restart_num) +{ + /* int ci; */ + + if (! flush_bits(state)) + return FALSE; + + emit_byte(state, 0xFF, return FALSE); + emit_byte(state, JPEG_RST0 + restart_num, return FALSE); + + /* The restart counter is not updated until we successfully write the MCU. */ + + return TRUE; +} + + +/* + * Encode and output one nMCU's worth of Huffman-compressed differences. + */ + +METHODDEF(JDIMENSION) +encode_mcus_huff (j_compress_ptr cinfo, JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, JDIMENSION MCU_col_num, + JDIMENSION nMCU) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsc->entropy_private; + working_state state; + unsigned int mcu_num; + int sampn, ci, yoffset, MCU_width, ptrn; + /* jpeg_component_info * compptr; */ + + /* Load up working state */ + state.next_output_byte = cinfo->dest->next_output_byte; + state.free_in_buffer = cinfo->dest->free_in_buffer; + ASSIGN_STATE(state.cur, entropy->saved); + state.cinfo = cinfo; + + /* Emit restart marker if needed */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! emit_restart(&state, entropy->next_restart_num)) + return 0; + } + + /* Set input pointer locations based on MCU_col_num */ + for (ptrn = 0; ptrn < entropy->num_input_ptrs; ptrn++) { + ci = entropy->input_ptr_info[ptrn].ci; + yoffset = entropy->input_ptr_info[ptrn].yoffset; + MCU_width = entropy->input_ptr_info[ptrn].MCU_width; + entropy->input_ptr[ptrn] = + diff_buf[ci][MCU_row_num + yoffset] + (MCU_col_num * MCU_width); + } + + for (mcu_num = 0; mcu_num < nMCU; mcu_num++) { + + /* Inner loop handles the samples in the MCU */ + for (sampn = 0; sampn < cinfo->data_units_in_MCU; sampn++) { + register int temp, temp2 /* , temp3 */ ; + register int nbits; + c_derived_tbl *dctbl = entropy->cur_tbls[sampn]; + + /* Encode the difference per section H.1.2.2 */ + + /* Input the sample difference */ + temp = *entropy->input_ptr[entropy->input_ptr_index[sampn]]++; + + if (temp & 0x8000) { /* instead of temp < 0 */ + temp = (-temp) & 0x7FFF; /* absolute value, mod 2^16 */ + if (temp == 0) /* special case: magnitude = 32768 */ + temp2 = temp = 0x8000; + temp2 = ~ temp; /* one's complement of magnitude */ + } else { + temp &= 0x7FFF; /* abs value mod 2^16 */ + temp2 = temp; /* magnitude */ + } + + /* Find the number of bits needed for the magnitude of the difference */ + nbits = 0; + while (temp) { + nbits++; + temp >>= 1; + } + /* Check for out-of-range difference values. + */ + if (nbits > MAX_DIFF_BITS) + ERREXIT(cinfo, JERR_BAD_DIFF); + + /* Emit the Huffman-coded symbol for the number of bits */ + if (! emit_bits(&state, dctbl->ehufco[nbits], dctbl->ehufsi[nbits])) + return mcu_num; + + /* Emit that number of bits of the value, if positive, */ + /* or the complement of its magnitude, if negative. */ + if (nbits && /* emit_bits rejects calls with size 0 */ + nbits != 16) /* special case: no bits should be emitted */ + if (! emit_bits(&state, (unsigned int) temp2, nbits)) + return mcu_num; + } + + /* Completed MCU, so update state */ + cinfo->dest->next_output_byte = state.next_output_byte; + cinfo->dest->free_in_buffer = state.free_in_buffer; + ASSIGN_STATE(entropy->saved, state.cur); + + /* Update restart-interval state too */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num++; + entropy->next_restart_num &= 7; + } + entropy->restarts_to_go--; + } + + } + + return nMCU; +} + + +/* + * Finish up at the end of a Huffman-compressed scan. + */ + +METHODDEF(void) +finish_pass_huff (j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsc->entropy_private; + working_state state; + + /* Load up working state ... flush_bits needs it */ + state.next_output_byte = cinfo->dest->next_output_byte; + state.free_in_buffer = cinfo->dest->free_in_buffer; + ASSIGN_STATE(state.cur, entropy->saved); + state.cinfo = cinfo; + + /* Flush out the last data */ + if (! flush_bits(&state)) + ERREXIT(cinfo, JERR_CANT_SUSPEND); + + /* Update state */ + cinfo->dest->next_output_byte = state.next_output_byte; + cinfo->dest->free_in_buffer = state.free_in_buffer; + ASSIGN_STATE(entropy->saved, state.cur); +} + + +/* + * Huffman coding optimization. + * + * We first scan the supplied data and count the number of uses of each symbol + * that is to be Huffman-coded. (This process MUST agree with the code above.) + * Then we build a Huffman coding tree for the observed counts. + * Symbols which are not needed at all for the particular image are not + * assigned any code, which saves space in the DHT marker as well as in + * the compressed data. + */ + +#ifdef ENTROPY_OPT_SUPPORTED + +/* + * Trial-encode one nMCU's worth of Huffman-compressed differences. + * No data is actually output, so no suspension return is possible. + */ + +METHODDEF(JDIMENSION) +encode_mcus_gather (j_compress_ptr cinfo, JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, JDIMENSION MCU_col_num, + JDIMENSION nMCU) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsc->entropy_private; + unsigned int mcu_num; + int sampn, ci, yoffset, MCU_width, ptrn; + /* jpeg_component_info * compptr; */ + + /* Take care of restart intervals if needed */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + /* Update restart state */ + entropy->restarts_to_go = cinfo->restart_interval; + } + entropy->restarts_to_go--; + } + + /* Set input pointer locations based on MCU_col_num */ + for (ptrn = 0; ptrn < entropy->num_input_ptrs; ptrn++) { + ci = entropy->input_ptr_info[ptrn].ci; + yoffset = entropy->input_ptr_info[ptrn].yoffset; + MCU_width = entropy->input_ptr_info[ptrn].MCU_width; + entropy->input_ptr[ptrn] = + diff_buf[ci][MCU_row_num + yoffset] + (MCU_col_num * MCU_width); + } + + for (mcu_num = 0; mcu_num < nMCU; mcu_num++) { + + /* Inner loop handles the samples in the MCU */ + for (sampn = 0; sampn < cinfo->data_units_in_MCU; sampn++) { + register int temp; + register int nbits; + /* c_derived_tbl *dctbl = entropy->cur_tbls[sampn]; */ + long * counts = entropy->cur_counts[sampn]; + + /* Encode the difference per section H.1.2.2 */ + + /* Input the sample difference */ + temp = *entropy->input_ptr[entropy->input_ptr_index[sampn]]++; + + if (temp & 0x8000) { /* instead of temp < 0 */ + temp = (-temp) & 0x7FFF; /* absolute value, mod 2^16 */ + if (temp == 0) /* special case: magnitude = 32768 */ + temp = 0x8000; + } else + temp &= 0x7FFF; /* abs value mod 2^16 */ + + /* Find the number of bits needed for the magnitude of the difference */ + nbits = 0; + while (temp) { + nbits++; + temp >>= 1; + } + /* Check for out-of-range difference values. + */ + if (nbits > MAX_DIFF_BITS) + ERREXIT(cinfo, JERR_BAD_DIFF); + + /* Count the Huffman symbol for the number of bits */ + counts[nbits]++; + } + } + + return nMCU; +} + + +/* + * Finish up a statistics-gathering pass and create the new Huffman tables. + */ + +METHODDEF(void) +finish_pass_gather (j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsc->entropy_private; + int ci, dctbl; + jpeg_component_info * compptr; + JHUFF_TBL **htblptr; + boolean did_dc[NUM_HUFF_TBLS]; + + /* It's important not to apply jpeg_gen_optimal_table more than once + * per table, because it clobbers the input frequency counts! + */ + MEMZERO(did_dc, SIZEOF(did_dc)); + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + dctbl = compptr->dc_tbl_no; + if (! did_dc[dctbl]) { + htblptr = & cinfo->dc_huff_tbl_ptrs[dctbl]; + if (*htblptr == NULL) + *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); + jpeg_gen_optimal_table(cinfo, *htblptr, entropy->count_ptrs[dctbl]); + did_dc[dctbl] = TRUE; + } + } +} + + +#endif /* ENTROPY_OPT_SUPPORTED */ + + +METHODDEF(boolean) +need_optimization_pass (j_compress_ptr cinfo) +{ + (void)cinfo; + return TRUE; +} + + +/* + * Module initialization routine for Huffman entropy encoding. + */ + +GLOBAL(void) +jinit_lhuff_encoder (j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + lhuff_entropy_ptr entropy; + int i; + + entropy = (lhuff_entropy_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(lhuff_entropy_encoder)); + losslsc->entropy_private = (struct jpeg_entropy_encoder *) entropy; + losslsc->pub.entropy_start_pass = start_pass_huff; + losslsc->pub.need_optimization_pass = need_optimization_pass; + + /* Mark tables unallocated */ + for (i = 0; i < NUM_HUFF_TBLS; i++) { + entropy->derived_tbls[i] = NULL; +#ifdef ENTROPY_OPT_SUPPORTED + entropy->count_ptrs[i] = NULL; +#endif + } +} diff --git a/src/gdcmjpeg/jclossls.c b/src/gdcmjpeg/jclossls.c new file mode 100644 index 00000000..34c95294 --- /dev/null +++ b/src/gdcmjpeg/jclossls.c @@ -0,0 +1,78 @@ +/* + * jclossls.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the control logic for the lossless JPEG compressor. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" + + +#ifdef C_LOSSLESS_SUPPORTED + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + + (*losslsc->scaler_start_pass) (cinfo); + (*losslsc->predict_start_pass) (cinfo); + (*losslsc->diff_start_pass) (cinfo, pass_mode); +} + + +/* + * Initialize the lossless compression codec. + * This is called only once, during master selection. + */ + +GLOBAL(void) +jinit_lossless_c_codec(j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc; + + /* Create subobject in permanent pool */ + losslsc = (j_lossless_c_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(jpeg_lossless_c_codec)); + cinfo->codec = (struct jpeg_c_codec *) losslsc; + + /* Initialize sub-modules */ + + /* Scaler */ + jinit_c_scaler(cinfo); + + /* Differencer */ + jinit_differencer(cinfo); + + /* Entropy encoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { + jinit_arith_encoder(cinfo); + } else { + jinit_lhuff_encoder(cinfo); + } + + /* Need a full-image difference buffer in any multi-pass mode. */ + jinit_c_diff_controller(cinfo, + (boolean) (cinfo->num_scans > 1 || + cinfo->optimize_coding)); + + /* Initialize method pointers. + * + * Note: entropy_start_pass and entropy_finish_pass are assigned in + * jclhuff.c and compress_data is assigned in jcdiffct.c. + */ + losslsc->pub.start_pass = start_pass; +} + +#endif /* C_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jclossy.c b/src/gdcmjpeg/jclossy.c new file mode 100644 index 00000000..44847140 --- /dev/null +++ b/src/gdcmjpeg/jclossy.c @@ -0,0 +1,76 @@ +/* + * jclossy.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the control logic for the lossy JPEG compressor. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + + (*lossyc->fdct_start_pass) (cinfo); + (*lossyc->coef_start_pass) (cinfo, pass_mode); +} + + +/* + * Initialize the lossy compression codec. + * This is called only once, during master selection. + */ + +GLOBAL(void) +jinit_lossy_c_codec (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc; + + /* Create subobject in permanent pool */ + lossyc = (j_lossy_c_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(jpeg_lossy_c_codec)); + cinfo->codec = (struct jpeg_c_codec *) lossyc; + + /* Initialize sub-modules */ + + /* Forward DCT */ + jinit_forward_dct(cinfo); + /* Entropy encoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { + jinit_arith_encoder(cinfo); + } else { + if (cinfo->process == JPROC_PROGRESSIVE) { +#ifdef C_PROGRESSIVE_SUPPORTED + jinit_phuff_encoder(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else + jinit_shuff_encoder(cinfo); + } + + /* Need a full-image coefficient buffer in any multi-pass mode. */ + jinit_c_coef_controller(cinfo, + (boolean) (cinfo->num_scans > 1 || + cinfo->optimize_coding)); + + /* Initialize method pointers. + * + * Note: entropy_start_pass and entropy_finish_pass are assigned in + * jcshuff.c or jcphuff.c and compress_data is assigned in jccoefct.c. + */ + lossyc->pub.start_pass = start_pass; +} diff --git a/src/gdcmjpeg/jcmainct.c b/src/gdcmjpeg/jcmainct.c new file mode 100644 index 00000000..e0cd678a --- /dev/null +++ b/src/gdcmjpeg/jcmainct.c @@ -0,0 +1,296 @@ +/* + * jcmainct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the main buffer controller for compression. + * The main buffer lies between the pre-processor and the JPEG + * compressor proper; it holds downsampled data in the JPEG colorspace. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Note: currently, there is no operating mode in which a full-image buffer + * is needed at this step. If there were, that mode could not be used with + * "raw data" input, since this module is bypassed in that case. However, + * we've left the code here for possible use in special applications. + */ +#undef FULL_MAIN_BUFFER_SUPPORTED + + +/* Private buffer controller object */ + +typedef struct { + struct jpeg_c_main_controller pub; /* public fields */ + + JDIMENSION cur_iMCU_row; /* number of current iMCU row */ + JDIMENSION rowgroup_ctr; /* counts row groups received in iMCU row */ + boolean suspended; /* remember if we suspended output */ + J_BUF_MODE pass_mode; /* current operating mode */ + + /* If using just a strip buffer, this points to the entire set of buffers + * (we allocate one for each component). In the full-image case, this + * points to the currently accessible strips of the virtual arrays. + */ + JSAMPARRAY buffer[MAX_COMPONENTS]; + +#ifdef FULL_MAIN_BUFFER_SUPPORTED + /* If using full-image storage, this array holds pointers to virtual-array + * control blocks for each component. Unused if not full-image storage. + */ + jvirt_sarray_ptr whole_image[MAX_COMPONENTS]; +#endif +} my_main_controller; + +typedef my_main_controller * my_main_ptr; + + +/* Forward declarations */ +METHODDEF(void) process_data_simple_main + JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf, + JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail)); +#ifdef FULL_MAIN_BUFFER_SUPPORTED +METHODDEF(void) process_data_buffer_main + JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf, + JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail)); +#endif + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_main (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + + /* Do nothing in raw-data mode. */ + if (cinfo->raw_data_in) + return; + + mainPtr->cur_iMCU_row = 0; /* initialize counters */ + mainPtr->rowgroup_ctr = 0; + mainPtr->suspended = FALSE; + mainPtr->pass_mode = pass_mode; /* save mode for use by process_data */ + + switch (pass_mode) { + case JBUF_PASS_THRU: +#ifdef FULL_MAIN_BUFFER_SUPPORTED + if (mainPtr->whole_image[0] != NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); +#endif + mainPtr->pub.process_data = process_data_simple_main; + break; +#ifdef FULL_MAIN_BUFFER_SUPPORTED + case JBUF_SAVE_SOURCE: + case JBUF_CRANK_DEST: + case JBUF_SAVE_AND_PASS: + if (mainPtr->whole_image[0] == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + mainPtr->pub.process_data = process_data_buffer_main; + break; +#endif + default: + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + break; + } +} + + +/* + * Process some data. + * This routine handles the simple pass-through mode, + * where we have only a strip buffer. + */ + +METHODDEF(void) +process_data_simple_main (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, + JDIMENSION in_rows_avail) +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + JDIMENSION data_unit = (JDIMENSION)(cinfo->data_unit); + + while (mainPtr->cur_iMCU_row < cinfo->total_iMCU_rows) { + /* Read input data if we haven't filled the main buffer yet */ + if (mainPtr->rowgroup_ctr < data_unit) + (*cinfo->prep->pre_process_data) (cinfo, + input_buf, in_row_ctr, in_rows_avail, + mainPtr->buffer, &mainPtr->rowgroup_ctr, + (JDIMENSION) data_unit); + + /* If we don't have a full iMCU row buffered, return to application for + * more data. Note that preprocessor will always pad to fill the iMCU row + * at the bottom of the image. + */ + if (mainPtr->rowgroup_ctr != data_unit) + return; + + /* Send the completed row to the compressor */ + if (! (*cinfo->codec->compress_data) (cinfo, mainPtr->buffer)) { + /* If compressor did not consume the whole row, then we must need to + * suspend processing and return to the application. In this situation + * we pretend we didn't yet consume the last input row; otherwise, if + * it happened to be the last row of the image, the application would + * think we were done. + */ + if (! mainPtr->suspended) { + (*in_row_ctr)--; + mainPtr->suspended = TRUE; + } + return; + } + /* We did finish the row. Undo our little suspension hack if a previous + * call suspended; then mark the main buffer empty. + */ + if (mainPtr->suspended) { + (*in_row_ctr)++; + mainPtr->suspended = FALSE; + } + mainPtr->rowgroup_ctr = 0; + mainPtr->cur_iMCU_row++; + } +} + + +#ifdef FULL_MAIN_BUFFER_SUPPORTED + +/* + * Process some data. + * This routine handles all of the modes that use a full-size buffer. + */ + +METHODDEF(void) +process_data_buffer_main (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, + JDIMENSION in_rows_avail) +{ + my_main_ptr main = (my_main_ptr) cinfo->main; + int ci; + jpeg_component_info *compptr; + boolean writing = (mainPtr->pass_mode != JBUF_CRANK_DEST); + JDIMENSION data_unit = (JDIMENSION)(cinfo->data_unit); + + while (mainPtr->cur_iMCU_row < cinfo->total_iMCU_rows) { + /* Realign the virtual buffers if at the start of an iMCU row. */ + if (mainPtr->rowgroup_ctr == 0) { + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + mainPtr->buffer[ci] = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, mainPtr->whole_image[ci], + mainPtr->cur_iMCU_row * (compptr->v_samp_factor * data_unit), + (JDIMENSION) (compptr->v_samp_factor * data_unit), writing); + } + /* In a read pass, pretend we just read some source data. */ + if (! writing) { + *in_row_ctr += cinfo->max_v_samp_factor * data_unit; + mainPtr->rowgroup_ctr = data_unit; + } + } + + /* If a write pass, read input data until the current iMCU row is full. */ + /* Note: preprocessor will pad if necessary to fill the last iMCU row. */ + if (writing) { + (*cinfo->prep->pre_process_data) (cinfo, + input_buf, in_row_ctr, in_rows_avail, + mainPtr->buffer, &mainPtr->rowgroup_ctr, + (JDIMENSION) data_unit); + /* Return to application if we need more data to fill the iMCU row. */ + if (mainPtr->rowgroup_ctr < data_unit) + return; + } + + /* Emit data, unless this is a sink-only pass. */ + if (mainPtr->pass_mode != JBUF_SAVE_SOURCE) { + if (! (*cinfo->codec->compress_data) (cinfo, mainPtr->buffer)) { + /* If compressor did not consume the whole row, then we must need to + * suspend processing and return to the application. In this situation + * we pretend we didn't yet consume the last input row; otherwise, if + * it happened to be the last row of the image, the application would + * think we were done. + */ + if (! mainPtr->suspended) { + (*in_row_ctr)--; + mainPtr->suspended = TRUE; + } + return; + } + /* We did finish the row. Undo our little suspension hack if a previous + * call suspended; then mark the main buffer empty. + */ + if (mainPtr->suspended) { + (*in_row_ctr)++; + mainPtr->suspended = FALSE; + } + } + + /* If get here, we are done with this iMCU row. Mark buffer empty. */ + mainPtr->rowgroup_ctr = 0; + mainPtr->cur_iMCU_row++; + } +} + +#endif /* FULL_MAIN_BUFFER_SUPPORTED */ + + +/* + * Initialize main buffer controller. + */ + +GLOBAL(void) +jinit_c_main_controller (j_compress_ptr cinfo, boolean need_full_buffer) +{ + my_main_ptr mainPtr; + int ci; + jpeg_component_info *compptr; + int data_unit = cinfo->data_unit; + + mainPtr = (my_main_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_main_controller)); + cinfo->main = (struct jpeg_c_main_controller *) mainPtr; + mainPtr->pub.start_pass = start_pass_main; + + /* We don't need to create a buffer in raw-data mode. */ + if (cinfo->raw_data_in) + return; + + /* Create the buffer. It holds downsampled data, so each component + * may be of a different size. + */ + if (need_full_buffer) { +#ifdef FULL_MAIN_BUFFER_SUPPORTED + /* Allocate a full-image virtual array for each component */ + /* Note we pad the bottom to a multiple of the iMCU height */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + mainPtr->whole_image[ci] = (*cinfo->mem->request_virt_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, + compptr->width_in_data_units * data_unit, + (JDIMENSION) jround_up((long) compptr->height_in_data_units, + (long) compptr->v_samp_factor) * data_unit, + (JDIMENSION) (compptr->v_samp_factor * data_unit)); + } +#else + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); +#endif + } else { +#ifdef FULL_MAIN_BUFFER_SUPPORTED + mainPtr->whole_image[0] = NULL; /* flag for no virtual arrays */ +#endif + /* Allocate a strip buffer for each component */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + mainPtr->buffer[ci] = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + compptr->width_in_data_units * data_unit, + (JDIMENSION) (compptr->v_samp_factor * data_unit)); + } + } +} diff --git a/src/gdcmjpeg/jcmarker.c b/src/gdcmjpeg/jcmarker.c new file mode 100644 index 00000000..fc388d57 --- /dev/null +++ b/src/gdcmjpeg/jcmarker.c @@ -0,0 +1,678 @@ +/* + * jcmarker.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains routines to write JPEG datastream markers. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +typedef enum { /* JPEG marker codes */ + M_SOF0 = 0xc0, + M_SOF1 = 0xc1, + M_SOF2 = 0xc2, + M_SOF3 = 0xc3, + + M_SOF5 = 0xc5, + M_SOF6 = 0xc6, + M_SOF7 = 0xc7, + + M_JPG = 0xc8, + M_SOF9 = 0xc9, + M_SOF10 = 0xca, + M_SOF11 = 0xcb, + + M_SOF13 = 0xcd, + M_SOF14 = 0xce, + M_SOF15 = 0xcf, + + M_DHT = 0xc4, + + M_DAC = 0xcc, + + M_RST0 = 0xd0, + M_RST1 = 0xd1, + M_RST2 = 0xd2, + M_RST3 = 0xd3, + M_RST4 = 0xd4, + M_RST5 = 0xd5, + M_RST6 = 0xd6, + M_RST7 = 0xd7, + + M_SOI = 0xd8, + M_EOI = 0xd9, + M_SOS = 0xda, + M_DQT = 0xdb, + M_DNL = 0xdc, + M_DRI = 0xdd, + M_DHP = 0xde, + M_EXP = 0xdf, + + M_APP0 = 0xe0, + M_APP1 = 0xe1, + M_APP2 = 0xe2, + M_APP3 = 0xe3, + M_APP4 = 0xe4, + M_APP5 = 0xe5, + M_APP6 = 0xe6, + M_APP7 = 0xe7, + M_APP8 = 0xe8, + M_APP9 = 0xe9, + M_APP10 = 0xea, + M_APP11 = 0xeb, + M_APP12 = 0xec, + M_APP13 = 0xed, + M_APP14 = 0xee, + M_APP15 = 0xef, + + M_JPG0 = 0xf0, + M_JPG13 = 0xfd, + M_COM = 0xfe, + + M_TEM = 0x01, + + M_ERROR = 0x100 +} JPEG_MARKER; + + +/* Private state */ + +typedef struct { + struct jpeg_marker_writer pub; /* public fields */ + + unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */ +} my_marker_writer; + +typedef my_marker_writer * my_marker_ptr; + + +/* + * Basic output routines. + * + * Note that we do not support suspension while writing a marker. + * Therefore, an application using suspension must ensure that there is + * enough buffer space for the initial markers (typ. 600-700 bytes) before + * calling jpeg_start_compress, and enough space to write the trailing EOI + * (a few bytes) before calling jpeg_finish_compress. Multipass compression + * modes are not supported at all with suspension, so those two are the only + * points where markers will be written. + */ + +LOCAL(void) +emit_byte (j_compress_ptr cinfo, int val) +/* Emit a byte */ +{ + struct jpeg_destination_mgr * dest = cinfo->dest; + + *(dest->next_output_byte)++ = (JOCTET) val; + if (--dest->free_in_buffer == 0) { + if (! (*dest->empty_output_buffer) (cinfo)) + ERREXIT(cinfo, JERR_CANT_SUSPEND); + } +} + + +LOCAL(void) +emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark) +/* Emit a marker code */ +{ + emit_byte(cinfo, 0xFF); + emit_byte(cinfo, (int) mark); +} + + +LOCAL(void) +emit_2bytes (j_compress_ptr cinfo, int value) +/* Emit a 2-byte integer; these are always MSB first in JPEG files */ +{ + emit_byte(cinfo, (value >> 8) & 0xFF); + emit_byte(cinfo, value & 0xFF); +} + + +/* + * Routines to write specific marker types. + */ + +LOCAL(int) +emit_dqt (j_compress_ptr cinfo, int index) +/* Emit a DQT marker */ +/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */ +{ + JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index]; + int prec; + int i; + + if (qtbl == NULL) + ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index); + + prec = 0; + for (i = 0; i < DCTSIZE2; i++) { + if (qtbl->quantval[i] > 255) + prec = 1; + } + + if (! qtbl->sent_table) { + emit_marker(cinfo, M_DQT); + + emit_2bytes(cinfo, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2); + + emit_byte(cinfo, index + (prec<<4)); + + for (i = 0; i < DCTSIZE2; i++) { + /* The table entries must be emitted in zigzag order. */ + unsigned int qval = qtbl->quantval[jpeg_natural_order[i]]; + if (prec) + emit_byte(cinfo, (int) (qval >> 8)); + emit_byte(cinfo, (int) (qval & 0xFF)); + } + + qtbl->sent_table = TRUE; + } + + return prec; +} + + +LOCAL(void) +emit_dht (j_compress_ptr cinfo, int index, boolean is_ac) +/* Emit a DHT marker */ +{ + JHUFF_TBL * htbl; + int length, i; + + if (is_ac) { + htbl = cinfo->ac_huff_tbl_ptrs[index]; + index += 0x10; /* output index has AC bit set */ + } else { + htbl = cinfo->dc_huff_tbl_ptrs[index]; + } + + if (htbl == NULL) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index); + + if (! htbl->sent_table) { + emit_marker(cinfo, M_DHT); + + length = 0; + for (i = 1; i <= 16; i++) + length += htbl->bits[i]; + + emit_2bytes(cinfo, length + 2 + 1 + 16); + emit_byte(cinfo, index); + + for (i = 1; i <= 16; i++) + emit_byte(cinfo, htbl->bits[i]); + + for (i = 0; i < length; i++) + emit_byte(cinfo, htbl->huffval[i]); + + htbl->sent_table = TRUE; + } +} + + +LOCAL(void) +emit_dac (j_compress_ptr cinfo) +/* Emit a DAC marker */ +/* Since the useful info is so small, we want to emit all the tables in */ +/* one DAC marker. Therefore this routine does its own scan of the table. */ +{ +#ifdef C_ARITH_CODING_SUPPORTED + char dc_in_use[NUM_ARITH_TBLS]; + char ac_in_use[NUM_ARITH_TBLS]; + int length, i; + jpeg_component_info *compptr; + + for (i = 0; i < NUM_ARITH_TBLS; i++) + dc_in_use[i] = ac_in_use[i] = 0; + + for (i = 0; i < cinfo->comps_in_scan; i++) { + compptr = cinfo->cur_comp_info[i]; + dc_in_use[compptr->dc_tbl_no] = 1; + ac_in_use[compptr->ac_tbl_no] = 1; + } + + length = 0; + for (i = 0; i < NUM_ARITH_TBLS; i++) + length += dc_in_use[i] + ac_in_use[i]; + + emit_marker(cinfo, M_DAC); + + emit_2bytes(cinfo, length*2 + 2); + + for (i = 0; i < NUM_ARITH_TBLS; i++) { + if (dc_in_use[i]) { + emit_byte(cinfo, i); + emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4)); + } + if (ac_in_use[i]) { + emit_byte(cinfo, i + 0x10); + emit_byte(cinfo, cinfo->arith_ac_K[i]); + } + } +#else + (void)cinfo; +#endif /* C_ARITH_CODING_SUPPORTED */ +} + + +LOCAL(void) +emit_dri (j_compress_ptr cinfo) +/* Emit a DRI marker */ +{ + emit_marker(cinfo, M_DRI); + + emit_2bytes(cinfo, 4); /* fixed length */ + + emit_2bytes(cinfo, (int) cinfo->restart_interval); +} + + +LOCAL(void) +emit_sof (j_compress_ptr cinfo, JPEG_MARKER code) +/* Emit a SOF marker */ +{ + int ci; + jpeg_component_info *compptr; + + emit_marker(cinfo, code); + + emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */ + + /* Make sure image isn't bigger than SOF field can handle */ + if ((long) cinfo->image_height > 65535L || + (long) cinfo->image_width > 65535L) + ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535); + + emit_byte(cinfo, cinfo->data_precision); + emit_2bytes(cinfo, (int) cinfo->image_height); + emit_2bytes(cinfo, (int) cinfo->image_width); + + emit_byte(cinfo, cinfo->num_components); + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + emit_byte(cinfo, compptr->component_id); + emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor); + emit_byte(cinfo, compptr->quant_tbl_no); + } +} + + +LOCAL(void) +emit_sos (j_compress_ptr cinfo) +/* Emit a SOS marker */ +{ + int i, td, ta; + jpeg_component_info *compptr; + + emit_marker(cinfo, M_SOS); + + emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */ + + emit_byte(cinfo, cinfo->comps_in_scan); + + for (i = 0; i < cinfo->comps_in_scan; i++) { + compptr = cinfo->cur_comp_info[i]; + emit_byte(cinfo, compptr->component_id); + td = compptr->dc_tbl_no; + ta = compptr->ac_tbl_no; + if (cinfo->process == JPROC_PROGRESSIVE) { + /* Progressive mode: only DC or only AC tables are used in one scan; + * furthermore, Huffman coding of DC refinement uses no table at all. + * We emit 0 for unused field(s); this is recommended by the P&M text + * but does not seem to be specified in the standard. + */ + if (cinfo->Ss == 0) { + ta = 0; /* DC scan */ + if (cinfo->Ah != 0 && !cinfo->arith_code) + td = 0; /* no DC table either */ + } else { + td = 0; /* AC scan */ + } + } + emit_byte(cinfo, (td << 4) + ta); + } + + emit_byte(cinfo, cinfo->Ss); + emit_byte(cinfo, cinfo->Se); + emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al); +} + + +LOCAL(void) +emit_jfif_app0 (j_compress_ptr cinfo) +/* Emit a JFIF-compliant APP0 marker */ +{ + /* + * Length of APP0 block (2 bytes) + * Block ID (4 bytes - ASCII "JFIF") + * Zero byte (1 byte to terminate the ID string) + * Version Major, Minor (2 bytes - major first) + * Units (1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm) + * Xdpu (2 bytes - dots per unit horizontal) + * Ydpu (2 bytes - dots per unit vertical) + * Thumbnail X size (1 byte) + * Thumbnail Y size (1 byte) + */ + + emit_marker(cinfo, M_APP0); + + emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */ + + emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */ + emit_byte(cinfo, 0x46); + emit_byte(cinfo, 0x49); + emit_byte(cinfo, 0x46); + emit_byte(cinfo, 0); + emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */ + emit_byte(cinfo, cinfo->JFIF_minor_version); + emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */ + emit_2bytes(cinfo, (int) cinfo->X_density); + emit_2bytes(cinfo, (int) cinfo->Y_density); + emit_byte(cinfo, 0); /* No thumbnail image */ + emit_byte(cinfo, 0); +} + + +LOCAL(void) +emit_adobe_app14 (j_compress_ptr cinfo) +/* Emit an Adobe APP14 marker */ +{ + /* + * Length of APP14 block (2 bytes) + * Block ID (5 bytes - ASCII "Adobe") + * Version Number (2 bytes - currently 100) + * Flags0 (2 bytes - currently 0) + * Flags1 (2 bytes - currently 0) + * Color transform (1 byte) + * + * Although Adobe TN 5116 mentions Version = 101, all the Adobe files + * now in circulation seem to use Version = 100, so that's what we write. + * + * We write the color transform byte as 1 if the JPEG color space is + * YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with + * whether the encoder performed a transformation, which is pretty useless. + */ + + emit_marker(cinfo, M_APP14); + + emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */ + + emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */ + emit_byte(cinfo, 0x64); + emit_byte(cinfo, 0x6F); + emit_byte(cinfo, 0x62); + emit_byte(cinfo, 0x65); + emit_2bytes(cinfo, 100); /* Version */ + emit_2bytes(cinfo, 0); /* Flags0 */ + emit_2bytes(cinfo, 0); /* Flags1 */ + switch (cinfo->jpeg_color_space) { + case JCS_YCbCr: + emit_byte(cinfo, 1); /* Color transform = 1 */ + break; + case JCS_YCCK: + emit_byte(cinfo, 2); /* Color transform = 2 */ + break; + default: + emit_byte(cinfo, 0); /* Color transform = 0 */ + break; + } +} + + +/* + * These routines allow writing an arbitrary marker with parameters. + * The only intended use is to emit COM or APPn markers after calling + * write_file_header and before calling write_frame_header. + * Other uses are not guaranteed to produce desirable results. + * Counting the parameter bytes properly is the caller's responsibility. + */ + +METHODDEF(void) +write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen) +/* Emit an arbitrary marker header */ +{ + if (datalen > (unsigned int) 65533) /* safety check */ + ERREXIT(cinfo, JERR_BAD_LENGTH); + + emit_marker(cinfo, (JPEG_MARKER) marker); + + emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */ +} + +METHODDEF(void) +write_marker_byte (j_compress_ptr cinfo, int val) +/* Emit one byte of marker parameters following write_marker_header */ +{ + emit_byte(cinfo, val); +} + + +/* + * Write datastream header. + * This consists of an SOI and optional APPn markers. + * We recommend use of the JFIF marker, but not the Adobe marker, + * when using YCbCr or grayscale data. The JFIF marker should NOT + * be used for any other JPEG colorspace. The Adobe marker is helpful + * to distinguish RGB, CMYK, and YCCK colorspaces. + * Note that an application can write additional header markers after + * jpeg_start_compress returns. + */ + +METHODDEF(void) +write_file_header (j_compress_ptr cinfo) +{ + my_marker_ptr marker = (my_marker_ptr) cinfo->marker; + + emit_marker(cinfo, M_SOI); /* first the SOI */ + + /* SOI is defined to reset restart interval to 0 */ + marker->last_restart_interval = 0; + + if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */ + emit_jfif_app0(cinfo); + if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */ + emit_adobe_app14(cinfo); +} + + +/* + * Write frame header. + * This consists of DQT and SOFn markers. + * Note that we do not emit the SOF until we have emitted the DQT(s). + * This avoids compatibility problems with incorrect implementations that + * try to error-check the quant table numbers as soon as they see the SOF. + */ + +METHODDEF(void) +write_frame_header (j_compress_ptr cinfo) +{ + int ci, prec; + boolean is_baseline; + jpeg_component_info *compptr; + + prec = 0; + if (cinfo->process != JPROC_LOSSLESS) { + /* Emit DQT for each quantization table. + * Note that emit_dqt() suppresses any duplicate tables. + */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + prec += emit_dqt(cinfo, compptr->quant_tbl_no); + } + /* now prec is nonzero iff there are any 16-bit quant tables. */ + } + + /* Check for a non-baseline specification. + * Note we assume that Huffman table numbers won't be changed later. + */ + if (cinfo->arith_code || cinfo->process != JPROC_SEQUENTIAL || + cinfo->data_precision != 8) { + is_baseline = FALSE; + } else { + is_baseline = TRUE; + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1) + is_baseline = FALSE; + } + if (prec && is_baseline) { + is_baseline = FALSE; + /* If it's baseline except for quantizer size, warn the user */ + TRACEMS(cinfo, 0, JTRC_16BIT_TABLES); + } + } + + /* Emit the proper SOF marker */ + if (cinfo->arith_code) { + if (cinfo->process == JPROC_PROGRESSIVE) + emit_sof(cinfo, M_SOF10); /* SOF code for progressive arithmetic */ + else if (cinfo->process == JPROC_LOSSLESS) + emit_sof(cinfo, M_SOF11); /* SOF code for lossless arithmetic */ + else + emit_sof(cinfo, M_SOF9); /* SOF code for sequential arithmetic */ + } else { + if (cinfo->process == JPROC_PROGRESSIVE) + emit_sof(cinfo, M_SOF2); /* SOF code for progressive Huffman */ + else if (cinfo->process == JPROC_LOSSLESS) + emit_sof(cinfo, M_SOF3); /* SOF code for lossless Huffman */ + else if (is_baseline) + emit_sof(cinfo, M_SOF0); /* SOF code for baseline implementation */ + else + emit_sof(cinfo, M_SOF1); /* SOF code for non-baseline Huffman file */ + } +} + + +/* + * Write scan header. + * This consists of DHT or DAC markers, optional DRI, and SOS. + * Compressed data will be written following the SOS. + */ + +METHODDEF(void) +write_scan_header (j_compress_ptr cinfo) +{ + my_marker_ptr marker = (my_marker_ptr) cinfo->marker; + int i; + jpeg_component_info *compptr; + + if (cinfo->arith_code) { + /* Emit arith conditioning info. We may have some duplication + * if the file has multiple scans, but it's so small it's hardly + * worth worrying about. + */ + emit_dac(cinfo); + } else { + /* Emit Huffman tables. + * Note that emit_dht() suppresses any duplicate tables. + */ + for (i = 0; i < cinfo->comps_in_scan; i++) { + compptr = cinfo->cur_comp_info[i]; + if (cinfo->process == JPROC_PROGRESSIVE) { + /* Progressive mode: only DC or only AC tables are used in one scan */ + if (cinfo->Ss == 0) { + if (cinfo->Ah == 0) /* DC needs no table for refinement scan */ + emit_dht(cinfo, compptr->dc_tbl_no, FALSE); + } else { + emit_dht(cinfo, compptr->ac_tbl_no, TRUE); + } + } else if (cinfo->process == JPROC_LOSSLESS) { + /* Lossless mode: only DC tables are used */ + emit_dht(cinfo, compptr->dc_tbl_no, FALSE); + } else { + /* Sequential mode: need both DC and AC tables */ + emit_dht(cinfo, compptr->dc_tbl_no, FALSE); + emit_dht(cinfo, compptr->ac_tbl_no, TRUE); + } + } + } + + /* Emit DRI if required --- note that DRI value could change for each scan. + * We avoid wasting space with unnecessary DRIs, however. + */ + if (cinfo->restart_interval != marker->last_restart_interval) { + emit_dri(cinfo); + marker->last_restart_interval = cinfo->restart_interval; + } + + emit_sos(cinfo); +} + + +/* + * Write datastream trailer. + */ + +METHODDEF(void) +write_file_trailer (j_compress_ptr cinfo) +{ + emit_marker(cinfo, M_EOI); +} + + +/* + * Write an abbreviated table-specification datastream. + * This consists of SOI, DQT and DHT tables, and EOI. + * Any table that is defined and not marked sent_table = TRUE will be + * emitted. Note that all tables will be marked sent_table = TRUE at exit. + */ + +METHODDEF(void) +write_tables_only (j_compress_ptr cinfo) +{ + int i; + + emit_marker(cinfo, M_SOI); + + for (i = 0; i < NUM_QUANT_TBLS; i++) { + if (cinfo->quant_tbl_ptrs[i] != NULL) + (void) emit_dqt(cinfo, i); + } + + if (! cinfo->arith_code) { + for (i = 0; i < NUM_HUFF_TBLS; i++) { + if (cinfo->dc_huff_tbl_ptrs[i] != NULL) + emit_dht(cinfo, i, FALSE); + if (cinfo->ac_huff_tbl_ptrs[i] != NULL) + emit_dht(cinfo, i, TRUE); + } + } + + emit_marker(cinfo, M_EOI); +} + + +/* + * Initialize the marker writer module. + */ + +GLOBAL(void) +jinit_marker_writer (j_compress_ptr cinfo) +{ + my_marker_ptr marker; + + /* Create the subobject */ + marker = (my_marker_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_marker_writer)); + cinfo->marker = (struct jpeg_marker_writer *) marker; + /* Initialize method pointers */ + marker->pub.write_file_header = write_file_header; + marker->pub.write_frame_header = write_frame_header; + marker->pub.write_scan_header = write_scan_header; + marker->pub.write_file_trailer = write_file_trailer; + marker->pub.write_tables_only = write_tables_only; + marker->pub.write_marker_header = write_marker_header; + marker->pub.write_marker_byte = write_marker_byte; + /* Initialize private state */ + marker->last_restart_interval = 0; +} diff --git a/src/gdcmjpeg/jcmaster.c b/src/gdcmjpeg/jcmaster.c new file mode 100644 index 00000000..c9851268 --- /dev/null +++ b/src/gdcmjpeg/jcmaster.c @@ -0,0 +1,648 @@ +/* + * jcmaster.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains master control logic for the JPEG compressor. + * These routines are concerned with parameter validation, initial setup, + * and inter-pass control (determining the number of passes and the work + * to be done in each pass). + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ + + +/* Private state */ + +typedef enum { + main_pass, /* input data, also do first output step */ + huff_opt_pass, /* Huffman code optimization pass */ + output_pass /* data output pass */ +} c_pass_type; + +typedef struct { + struct jpeg_comp_master pub; /* public fields */ + + c_pass_type pass_type; /* the type of the current pass */ + + int pass_number; /* # of passes completed */ + int total_passes; /* total # of passes needed */ + + int scan_number; /* current index in scan_info[] */ +} my_comp_master; + +typedef my_comp_master * my_master_ptr; + + +/* + * Support routines that do various essential calculations. + */ + +LOCAL(void) +initial_setup (j_compress_ptr cinfo) +/* Do computations that are needed before master selection phase */ +{ + int ci; + jpeg_component_info *compptr; + long samplesperrow; + JDIMENSION jd_samplesperrow; + int data_unit = cinfo->data_unit; + + /* Sanity check on image dimensions */ + if (cinfo->image_height <= 0 || cinfo->image_width <= 0 + || cinfo->num_components <= 0 || cinfo->input_components <= 0) + ERREXIT(cinfo, JERR_EMPTY_IMAGE); + + /* Make sure image isn't bigger than I can handle */ + if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION || + (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION) + ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION); + + /* Width of an input scanline must be representable as JDIMENSION. */ + samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components; + jd_samplesperrow = (JDIMENSION) samplesperrow; + if ((long) jd_samplesperrow != samplesperrow) + ERREXIT(cinfo, JERR_WIDTH_OVERFLOW); + + /* For now, precision must match compiled-in value... */ + if (cinfo->data_precision != BITS_IN_JSAMPLE) + ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); + + /* Check that number of components won't exceed internal array sizes */ + if (cinfo->num_components > MAX_COMPONENTS) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, + MAX_COMPONENTS); + + /* Compute maximum sampling factors; check factor validity */ + cinfo->max_h_samp_factor = 1; + cinfo->max_v_samp_factor = 1; + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR || + compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR) + ERREXIT(cinfo, JERR_BAD_SAMPLING); + cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor, + compptr->h_samp_factor); + cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor, + compptr->v_samp_factor); + } + + /* Compute dimensions of components */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Fill in the correct component_index value; don't rely on application */ + compptr->component_index = ci; + /* For compression, we never do any codec-based processing. */ + compptr->codec_data_unit = data_unit; + /* Size in data units */ + compptr->width_in_data_units = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, + (long) (cinfo->max_h_samp_factor * data_unit)); + compptr->height_in_data_units = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, + (long) (cinfo->max_v_samp_factor * data_unit)); + /* Size in samples */ + compptr->downsampled_width = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, + (long) cinfo->max_h_samp_factor); + compptr->downsampled_height = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, + (long) cinfo->max_v_samp_factor); + /* Mark component needed (this flag isn't actually used for compression) */ + compptr->component_needed = TRUE; + } + + /* Compute number of fully interleaved MCU rows (number of times that + * main controller will call coefficient controller). + */ + cinfo->total_iMCU_rows = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, + (long) (cinfo->max_v_samp_factor*data_unit)); +} + +#ifdef C_MULTISCAN_FILES_SUPPORTED +#define NEED_SCAN_SCRIPT +#else +#ifdef C_LOSSLESS_SUPPORTED +#define NEED_SCAN_SCRIPT +#endif +#endif + +#ifdef NEED_SCAN_SCRIPT + +LOCAL(void) +validate_script (j_compress_ptr cinfo) +/* Verify that the scan script in cinfo->scan_info[] is valid; also + * determine whether it uses progressive JPEG, and set cinfo->process. + */ +{ + const jpeg_scan_info * scanptr; + int scanno, ncomps, ci, coefi, thisi; + int Ss, Se, Ah, Al; + boolean component_sent[MAX_COMPONENTS]; +#ifdef C_PROGRESSIVE_SUPPORTED + int * last_bitpos_ptr; + int last_bitpos[MAX_COMPONENTS][DCTSIZE2]; + /* -1 until that coefficient has been seen; then last Al for it */ +#endif + + if (cinfo->num_scans <= 0) + ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0); + +#ifndef C_MULTISCAN_FILES_SUPPORTED + if (cinfo->num_scans > 1) + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + + scanptr = cinfo->scan_info; + if (cinfo->lossless) { +#ifdef C_LOSSLESS_SUPPORTED + cinfo->process = JPROC_LOSSLESS; + for (ci = 0; ci < cinfo->num_components; ci++) + component_sent[ci] = FALSE; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } + /* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1; + * for progressive JPEG, no scan can have this. + */ + else if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) { +#ifdef C_PROGRESSIVE_SUPPORTED + cinfo->process = JPROC_PROGRESSIVE; + last_bitpos_ptr = & last_bitpos[0][0]; + for (ci = 0; ci < cinfo->num_components; ci++) + for (coefi = 0; coefi < DCTSIZE2; coefi++) + *last_bitpos_ptr++ = -1; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + cinfo->process = JPROC_SEQUENTIAL; + for (ci = 0; ci < cinfo->num_components; ci++) + component_sent[ci] = FALSE; + } + + for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) { + /* Validate component indexes */ + ncomps = scanptr->comps_in_scan; + if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN); + for (ci = 0; ci < ncomps; ci++) { + thisi = scanptr->component_index[ci]; + if (thisi < 0 || thisi >= cinfo->num_components) + ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno); + /* Components must appear in SOF order within each scan */ + if (ci > 0 && thisi <= scanptr->component_index[ci-1]) + ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno); + } + /* Validate progression parameters */ + Ss = scanptr->Ss; + Se = scanptr->Se; + Ah = scanptr->Ah; + Al = scanptr->Al; + if (cinfo->process == JPROC_LOSSLESS) { +#ifdef C_LOSSLESS_SUPPORTED + /* The JPEG spec simply gives the range 0..15 for Al (Pt), but that + * seems wrong: the upper bound ought to depend on data precision. + * Perhaps they really meant 0..N-1 for N-bit precision, which is what + * we allow here. + */ + if (Ss < 1 || Ss > 7 || /* predictor selector */ + Se != 0 || Ah != 0 || + Al < 0 || Al >= cinfo->data_precision) /* point transform */ + ERREXIT1(cinfo, JERR_BAD_LOSSLESS_SCRIPT, scanno); + /* Make sure components are not sent twice */ + for (ci = 0; ci < ncomps; ci++) { + thisi = scanptr->component_index[ci]; + if (component_sent[thisi]) + ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno); + component_sent[thisi] = TRUE; + } +#endif + } else if (cinfo->process == JPROC_PROGRESSIVE) { +#ifdef C_PROGRESSIVE_SUPPORTED + /* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that + * seems wrong: the upper bound ought to depend on data precision. + * Perhaps they really meant 0..N+1 for N-bit precision. + * Here we allow 0..10 for 8-bit data; Al larger than 10 results in + * out-of-range reconstructed DC values during the first DC scan, + * which might cause problems for some decoders. + */ +#if BITS_IN_JSAMPLE == 8 +#define MAX_AH_AL 10 +#else +#define MAX_AH_AL 13 +#endif + if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 || + Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL) + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + if (Ss == 0) { + if (Se != 0) /* DC and AC together not OK */ + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + } else { + if (ncomps != 1) /* AC scans must be for only one component */ + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + } + for (ci = 0; ci < ncomps; ci++) { + last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0]; + if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */ + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + for (coefi = Ss; coefi <= Se; coefi++) { + if (last_bitpos_ptr[coefi] < 0) { + /* first scan of this coefficient */ + if (Ah != 0) + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + } else { + /* not first scan */ + if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1) + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + } + last_bitpos_ptr[coefi] = Al; + } + } +#endif + } else { + /* For sequential JPEG, all progression parameters must be these: */ + if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0) + ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno); + /* Make sure components are not sent twice */ + for (ci = 0; ci < ncomps; ci++) { + thisi = scanptr->component_index[ci]; + if (component_sent[thisi]) + ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno); + component_sent[thisi] = TRUE; + } + } + } + + /* Now verify that everything got sent. */ + if (cinfo->process == JPROC_PROGRESSIVE) { +#ifdef C_PROGRESSIVE_SUPPORTED + /* For progressive mode, we only check that at least some DC data + * got sent for each component; the spec does not require that all bits + * of all coefficients be transmitted. Would it be wiser to enforce + * transmission of all coefficient bits?? + */ + for (ci = 0; ci < cinfo->num_components; ci++) { + if (last_bitpos[ci][0] < 0) + ERREXIT(cinfo, JERR_MISSING_DATA); + } +#endif + } else { + for (ci = 0; ci < cinfo->num_components; ci++) { + if (! component_sent[ci]) + ERREXIT(cinfo, JERR_MISSING_DATA); + } + } +} + +#endif /* NEED_SCAN_SCRIPT */ + + +LOCAL(void) +select_scan_parameters (j_compress_ptr cinfo) +/* Set up the scan parameters for the current scan */ +{ + int ci; + +#ifdef NEED_SCAN_SCRIPT + if (cinfo->scan_info != NULL) { + /* Prepare for current scan --- the script is already validated */ + my_master_ptr master = (my_master_ptr) cinfo->master; + const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number; + + cinfo->comps_in_scan = scanptr->comps_in_scan; + for (ci = 0; ci < scanptr->comps_in_scan; ci++) { + cinfo->cur_comp_info[ci] = + &cinfo->comp_info[scanptr->component_index[ci]]; + } + cinfo->Ss = scanptr->Ss; + cinfo->Se = scanptr->Se; + cinfo->Ah = scanptr->Ah; + cinfo->Al = scanptr->Al; + } else +#endif + { + /* Prepare for single sequential-JPEG scan containing all components */ + if (cinfo->num_components > MAX_COMPS_IN_SCAN) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, + MAX_COMPS_IN_SCAN); + cinfo->comps_in_scan = cinfo->num_components; + for (ci = 0; ci < cinfo->num_components; ci++) { + cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci]; + } + if (cinfo->lossless) { +#ifdef C_LOSSLESS_SUPPORTED + /* If we fall through to here, the user specified lossless, but did not + * provide a scan script. + */ + ERREXIT(cinfo, JERR_NO_LOSSLESS_SCRIPT); +#endif + } else { + cinfo->process = JPROC_SEQUENTIAL; + cinfo->Ss = 0; + cinfo->Se = DCTSIZE2-1; + cinfo->Ah = 0; + cinfo->Al = 0; + } + } +} + + +LOCAL(void) +per_scan_setup (j_compress_ptr cinfo) +/* Do computations that are needed before processing a JPEG scan */ +/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */ +{ + int ci, mcublks, tmp; + jpeg_component_info *compptr; + int data_unit = cinfo->data_unit; + + if (cinfo->comps_in_scan == 1) { + + /* Noninterleaved (single-component) scan */ + compptr = cinfo->cur_comp_info[0]; + + /* Overall image size in MCUs */ + cinfo->MCUs_per_row = compptr->width_in_data_units; + cinfo->MCU_rows_in_scan = compptr->height_in_data_units; + + /* For noninterleaved scan, always one block per MCU */ + compptr->MCU_width = 1; + compptr->MCU_height = 1; + compptr->MCU_data_units = 1; + compptr->MCU_sample_width = data_unit; + compptr->last_col_width = 1; + /* For noninterleaved scans, it is convenient to define last_row_height + * as the number of block rows present in the last iMCU row. + */ + tmp = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (tmp == 0) tmp = compptr->v_samp_factor; + compptr->last_row_height = tmp; + + /* Prepare array describing MCU composition */ + cinfo->data_units_in_MCU = 1; + cinfo->MCU_membership[0] = 0; + + } else { + + /* Interleaved (multi-component) scan */ + if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan, + MAX_COMPS_IN_SCAN); + + /* Overall image size in MCUs */ + cinfo->MCUs_per_row = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width, + (long) (cinfo->max_h_samp_factor*data_unit)); + cinfo->MCU_rows_in_scan = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, + (long) (cinfo->max_v_samp_factor*data_unit)); + + cinfo->data_units_in_MCU = 0; + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + /* Sampling factors give # of blocks of component in each MCU */ + compptr->MCU_width = compptr->h_samp_factor; + compptr->MCU_height = compptr->v_samp_factor; + compptr->MCU_data_units = compptr->MCU_width * compptr->MCU_height; + compptr->MCU_sample_width = compptr->MCU_width * data_unit; + /* Figure number of non-dummy blocks in last MCU column & row */ + tmp = (int) (compptr->width_in_data_units % compptr->MCU_width); + if (tmp == 0) tmp = compptr->MCU_width; + compptr->last_col_width = tmp; + tmp = (int) (compptr->height_in_data_units % compptr->MCU_height); + if (tmp == 0) tmp = compptr->MCU_height; + compptr->last_row_height = tmp; + /* Prepare array describing MCU composition */ + mcublks = compptr->MCU_data_units; + if (cinfo->data_units_in_MCU + mcublks > C_MAX_DATA_UNITS_IN_MCU) + ERREXIT(cinfo, JERR_BAD_MCU_SIZE); + while (mcublks-- > 0) { + cinfo->MCU_membership[cinfo->data_units_in_MCU++] = ci; + } + } + + } + + /* Convert restart specified in rows to actual MCU count. */ + /* Note that count must fit in 16 bits, so we provide limiting. */ + if (cinfo->restart_in_rows > 0) { + long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row; + cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L); + } +} + + +/* + * Per-pass setup. + * This is called at the beginning of each pass. We determine which modules + * will be active during this pass and give them appropriate start_pass calls. + * We also set is_last_pass to indicate whether any more passes will be + * required. + */ + +METHODDEF(void) +prepare_for_pass (j_compress_ptr cinfo) +{ + /* j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; */ + my_master_ptr master = (my_master_ptr) cinfo->master; + + switch (master->pass_type) { + case main_pass: + /* Initial pass: will collect input data, and do either Huffman + * optimization or data output for the first scan. + */ + select_scan_parameters(cinfo); + per_scan_setup(cinfo); + if (! cinfo->raw_data_in) { + (*cinfo->cconvert->start_pass) (cinfo); + (*cinfo->downsample->start_pass) (cinfo); + (*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU); + } + (*cinfo->codec->entropy_start_pass) (cinfo, cinfo->optimize_coding); + (*cinfo->codec->start_pass) (cinfo, + (master->total_passes > 1 ? + JBUF_SAVE_AND_PASS : JBUF_PASS_THRU)); + (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU); + if (cinfo->optimize_coding) { + /* No immediate data output; postpone writing frame/scan headers */ + master->pub.call_pass_startup = FALSE; + } else { + /* Will write frame/scan headers at first jpeg_write_scanlines call */ + master->pub.call_pass_startup = TRUE; + } + break; +#ifdef ENTROPY_OPT_SUPPORTED + case huff_opt_pass: + /* Do Huffman optimization for a scan after the first one. */ + select_scan_parameters(cinfo); + per_scan_setup(cinfo); + if ((*cinfo->codec->need_optimization_pass) (cinfo)) { + (*cinfo->codec->entropy_start_pass) (cinfo, TRUE); + (*cinfo->codec->start_pass) (cinfo, JBUF_CRANK_DEST); + master->pub.call_pass_startup = FALSE; + break; + } + /* Special case: Huffman DC refinement scans need no Huffman table + * and therefore we can skip the optimization pass for them. + */ + master->pass_type = output_pass; + master->pass_number++; + /*FALLTHROUGH*/ +#endif + case output_pass: + /* Do a data-output pass. */ + /* We need not repeat per-scan setup if prior optimization pass did it. */ + if (! cinfo->optimize_coding) { + select_scan_parameters(cinfo); + per_scan_setup(cinfo); + } + (*cinfo->codec->entropy_start_pass) (cinfo, FALSE); + (*cinfo->codec->start_pass) (cinfo, JBUF_CRANK_DEST); + /* We emit frame/scan headers now */ + if (master->scan_number == 0) + (*cinfo->marker->write_frame_header) (cinfo); + (*cinfo->marker->write_scan_header) (cinfo); + master->pub.call_pass_startup = FALSE; + break; + default: + ERREXIT(cinfo, JERR_NOT_COMPILED); + } + + master->pub.is_last_pass = (master->pass_number == master->total_passes-1); + + /* Set up progress monitor's pass info if present */ + if (cinfo->progress != NULL) { + cinfo->progress->completed_passes = master->pass_number; + cinfo->progress->total_passes = master->total_passes; + } +} + + +/* + * Special start-of-pass hook. + * This is called by jpeg_write_scanlines if call_pass_startup is TRUE. + * In single-pass processing, we need this hook because we don't want to + * write frame/scan headers during jpeg_start_compress; we want to let the + * application write COM markers etc. between jpeg_start_compress and the + * jpeg_write_scanlines loop. + * In multi-pass processing, this routine is not used. + */ + +METHODDEF(void) +pass_startup (j_compress_ptr cinfo) +{ + cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */ + + (*cinfo->marker->write_frame_header) (cinfo); + (*cinfo->marker->write_scan_header) (cinfo); +} + + +/* + * Finish up at end of pass. + */ + +METHODDEF(void) +finish_pass_master (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + my_master_ptr master = (my_master_ptr) cinfo->master; + + /* The entropy coder always needs an end-of-pass call, + * either to analyze statistics or to flush its output buffer. + */ + (*lossyc->pub.entropy_finish_pass) (cinfo); + + /* Update state for next pass */ + switch (master->pass_type) { + case main_pass: + /* next pass is either output of scan 0 (after optimization) + * or output of scan 1 (if no optimization). + */ + master->pass_type = output_pass; + if (! cinfo->optimize_coding) + master->scan_number++; + break; + case huff_opt_pass: + /* next pass is always output of current scan */ + master->pass_type = output_pass; + break; + case output_pass: + /* next pass is either optimization or output of next scan */ + if (cinfo->optimize_coding) + master->pass_type = huff_opt_pass; + master->scan_number++; + break; + } + + master->pass_number++; +} + + +/* + * Initialize master compression control. + */ + +GLOBAL(void) +jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only) +{ + my_master_ptr master; + + master = (my_master_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_comp_master)); + cinfo->master = (struct jpeg_comp_master *) master; + master->pub.prepare_for_pass = prepare_for_pass; + master->pub.pass_startup = pass_startup; + master->pub.finish_pass = finish_pass_master; + master->pub.is_last_pass = FALSE; + + cinfo->data_unit = cinfo->lossless ? 1 : DCTSIZE; + + /* Validate parameters, determine derived values */ + initial_setup(cinfo); + + if (cinfo->scan_info != NULL) { +#ifdef NEED_SCAN_SCRIPT + validate_script(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + cinfo->process = JPROC_SEQUENTIAL; + cinfo->num_scans = 1; + } + + if ((cinfo->arith_code == 0) && + (cinfo->process == JPROC_PROGRESSIVE || /* TEMPORARY HACK ??? */ + cinfo->process == JPROC_LOSSLESS)) + cinfo->optimize_coding = TRUE; /* assume default tables no good for + * progressive mode or lossless mode */ + + /* Initialize my private state */ + if (transcode_only) { + /* no main pass in transcoding */ + if (cinfo->optimize_coding) + master->pass_type = huff_opt_pass; + else + master->pass_type = output_pass; + } else { + /* for normal compression, first pass is always this type: */ + master->pass_type = main_pass; + } + master->scan_number = 0; + master->pass_number = 0; + if (cinfo->optimize_coding) + master->total_passes = cinfo->num_scans * 2; + else + master->total_passes = cinfo->num_scans; +} diff --git a/src/gdcmjpeg/jcodec.c b/src/gdcmjpeg/jcodec.c new file mode 100644 index 00000000..9529caaa --- /dev/null +++ b/src/gdcmjpeg/jcodec.c @@ -0,0 +1,53 @@ +/* + * jcodec.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains utility functions for the JPEG codec(s). + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" +#include "jlossls.h" + + +/* + * Initialize the compression codec. + * This is called only once, during master selection. + */ + +GLOBAL(void) +jinit_c_codec (j_compress_ptr cinfo) +{ + if (cinfo->process == JPROC_LOSSLESS) { +#ifdef C_LOSSLESS_SUPPORTED + jinit_lossless_c_codec(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else + jinit_lossy_c_codec(cinfo); +} + + +/* + * Initialize the decompression codec. + * This is called only once, during master selection. + */ + +GLOBAL(void) +jinit_d_codec (j_decompress_ptr cinfo) +{ + if (cinfo->process == JPROC_LOSSLESS) { +#ifdef D_LOSSLESS_SUPPORTED + jinit_lossless_d_codec(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else + jinit_lossy_d_codec(cinfo); +} diff --git a/src/gdcmjpeg/jcomapi.c b/src/gdcmjpeg/jcomapi.c new file mode 100644 index 00000000..2d45449a --- /dev/null +++ b/src/gdcmjpeg/jcomapi.c @@ -0,0 +1,106 @@ +/* + * jcomapi.c + * + * Copyright (C) 1994-1997, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains application interface routines that are used for both + * compression and decompression. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Abort processing of a JPEG compression or decompression operation, + * but don't destroy the object itself. + * + * For this, we merely clean up all the nonpermanent memory pools. + * Note that temp files (virtual arrays) are not allowed to belong to + * the permanent pool, so we will be able to close all temp files here. + * Closing a data source or destination, if necessary, is the application's + * responsibility. + */ + +GLOBAL(void) +jpeg_abort (j_common_ptr cinfo) +{ + int pool; + + /* Do nothing if called on a not-initialized or destroyed JPEG object. */ + if (cinfo->mem == NULL) + return; + + /* Releasing pools in reverse order might help avoid fragmentation + * with some (brain-damaged) malloc libraries. + */ + for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) { + (*cinfo->mem->free_pool) (cinfo, pool); + } + + /* Reset overall state for possible reuse of object */ + if (cinfo->is_decompressor) { + cinfo->global_state = DSTATE_START; + /* Try to keep application from accessing now-deleted marker list. + * A bit kludgy to do it here, but this is the most central place. + */ + ((j_decompress_ptr) cinfo)->marker_list = NULL; + } else { + cinfo->global_state = CSTATE_START; + } +} + + +/* + * Destruction of a JPEG object. + * + * Everything gets deallocated except the master jpeg_compress_struct itself + * and the error manager struct. Both of these are supplied by the application + * and must be freed, if necessary, by the application. (Often they are on + * the stack and so don't need to be freed anyway.) + * Closing a data source or destination, if necessary, is the application's + * responsibility. + */ + +GLOBAL(void) +jpeg_destroy (j_common_ptr cinfo) +{ + /* We need only tell the memory manager to release everything. */ + /* NB: mem pointer is NULL if memory mgr failed to initialize. */ + if (cinfo->mem != NULL) + (*cinfo->mem->self_destruct) (cinfo); + cinfo->mem = NULL; /* be safe if jpeg_destroy is called twice */ + cinfo->global_state = 0; /* mark it destroyed */ +} + + +/* + * Convenience routines for allocating quantization and Huffman tables. + * (Would jutils.c be a more reasonable place to put these?) + */ + +GLOBAL(JQUANT_TBL *) +jpeg_alloc_quant_table (j_common_ptr cinfo) +{ + JQUANT_TBL *tbl; + + tbl = (JQUANT_TBL *) + (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL)); + tbl->sent_table = FALSE; /* make sure this is false in any new table */ + return tbl; +} + + +GLOBAL(JHUFF_TBL *) +jpeg_alloc_huff_table (j_common_ptr cinfo) +{ + JHUFF_TBL *tbl; + + tbl = (JHUFF_TBL *) + (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL)); + tbl->sent_table = FALSE; /* make sure this is false in any new table */ + return tbl; +} diff --git a/src/gdcmjpeg/jconfig.doc b/src/gdcmjpeg/jconfig.doc new file mode 100644 index 00000000..c18d1c06 --- /dev/null +++ b/src/gdcmjpeg/jconfig.doc @@ -0,0 +1,155 @@ +/* + * jconfig.doc + * + * Copyright (C) 1991-1994, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file documents the configuration options that are required to + * customize the JPEG software for a particular system. + * + * The actual configuration options for a particular installation are stored + * in jconfig.h. On many machines, jconfig.h can be generated automatically + * or copied from one of the "canned" jconfig files that we supply. But if + * you need to generate a jconfig.h file by hand, this file tells you how. + * + * DO NOT EDIT THIS FILE --- IT WON'T ACCOMPLISH ANYTHING. + * EDIT A COPY NAMED JCONFIG.H. + */ + + +/* + * These symbols indicate the properties of your machine or compiler. + * #define the symbol if yes, #undef it if no. + */ + +/* Does your compiler support function prototypes? + * (If not, you also need to use ansi2knr, see install.doc) + */ +#define HAVE_PROTOTYPES + +/* Does your compiler support the declaration "unsigned char" ? + * How about "unsigned short" ? + */ +#define HAVE_UNSIGNED_CHAR +#define HAVE_UNSIGNED_SHORT + +/* Define "void" as "char" if your compiler doesn't know about type void. + * NOTE: be sure to define void such that "void *" represents the most general + * pointer type, e.g., that returned by malloc(). + */ +/* #define void char */ + +/* Define "const" as empty if your compiler doesn't know the "const" keyword. + */ +/* #define const */ + +/* Define this if an ordinary "char" type is unsigned. + * If you're not sure, leaving it undefined will work at some cost in speed. + * If you defined HAVE_UNSIGNED_CHAR then the speed difference is minimal. + */ +#undef CHAR_IS_UNSIGNED + +/* Define this if your system has an ANSI-conforming file. + */ +#define HAVE_STDDEF_H + +/* Define this if your system has an ANSI-conforming file. + */ +#define HAVE_STDLIB_H + +/* Define this if your system does not have an ANSI/SysV , + * but does have a BSD-style . + */ +#undef NEED_BSD_STRINGS + +/* Define this if your system does not provide typedef size_t in any of the + * ANSI-standard places (stddef.h, stdlib.h, or stdio.h), but places it in + * instead. + */ +#undef NEED_SYS_TYPES_H + +/* For 80x86 machines, you need to define NEED_FAR_POINTERS, + * unless you are using a large-data memory model or 80386 flat-memory mode. + * On less brain-damaged CPUs this symbol must not be defined. + * (Defining this symbol causes large data structures to be referenced through + * "far" pointers and to be allocated with a special version of malloc.) + */ +#undef NEED_FAR_POINTERS + +/* Define this if your linker needs global names to be unique in less + * than the first 15 characters. + */ +#undef NEED_SHORT_EXTERNAL_NAMES + +/* Although a real ANSI C compiler can deal perfectly well with pointers to + * unspecified structures (see "incomplete types" in the spec), a few pre-ANSI + * and pseudo-ANSI compilers get confused. To keep one of these bozos happy, + * define INCOMPLETE_TYPES_BROKEN. This is not recommended unless you + * actually get "missing structure definition" warnings or errors while + * compiling the JPEG code. + */ +#undef INCOMPLETE_TYPES_BROKEN + + +/* + * The following options affect code selection within the JPEG library, + * but they don't need to be visible to applications using the library. + * To minimize application namespace pollution, the symbols won't be + * defined unless JPEG_INTERNALS has been defined. + */ + +#ifdef JPEG_INTERNALS + +/* Define this if your compiler implements ">>" on signed values as a logical + * (unsigned) shift; leave it undefined if ">>" is a signed (arithmetic) shift, + * which is the normal and rational definition. + */ +#undef RIGHT_SHIFT_IS_UNSIGNED + + +#endif /* JPEG_INTERNALS */ + + +/* + * The remaining options do not affect the JPEG library proper, + * but only the sample applications cjpeg/djpeg (see cjpeg.c, djpeg.c). + * Other applications can ignore these. + */ + +#ifdef JPEG_CJPEG_DJPEG + +/* These defines indicate which image (non-JPEG) file formats are allowed. */ + +#define BMP_SUPPORTED /* BMP image file format */ +#define GIF_SUPPORTED /* GIF image file format */ +#define PPM_SUPPORTED /* PBMPLUS PPM/PGM image file format */ +#undef RLE_SUPPORTED /* Utah RLE image file format */ +#define TARGA_SUPPORTED /* Targa image file format */ + +/* Define this if you want to name both input and output files on the command + * line, rather than using stdout and optionally stdin. You MUST do this if + * your system can't cope with binary I/O to stdin/stdout. See comments at + * head of cjpeg.c or djpeg.c. + */ +#undef TWO_FILE_COMMANDLINE + +/* Define this if your system needs explicit cleanup of temporary files. + * This is crucial under MS-DOS, where the temporary "files" may be areas + * of extended memory; on most other systems it's not as important. + */ +#undef NEED_SIGNAL_CATCHER + +/* By default, we open image files with fopen(...,"rb") or fopen(...,"wb"). + * This is necessary on systems that distinguish text files from binary files, + * and is harmless on most systems that don't. If you have one of the rare + * systems that complains about the "b" spec, define this symbol. + */ +#undef DONT_USE_B_MODE + +/* Define this if you want percent-done progress reports from cjpeg/djpeg. + */ +#undef PROGRESS_REPORT + + +#endif /* JPEG_CJPEG_DJPEG */ diff --git a/src/gdcmjpeg/jconfig.h.in b/src/gdcmjpeg/jconfig.h.in new file mode 100644 index 00000000..66aaa74b --- /dev/null +++ b/src/gdcmjpeg/jconfig.h.in @@ -0,0 +1,69 @@ +/* jconfig.h --- source file edited by configure script */ +/* see jconfig.doc for explanations */ + +#define HAVE_PROTOTYPES +#define HAVE_UNSIGNED_CHAR +#define HAVE_UNSIGNED_SHORT +#undef void +#undef const +#undef CHAR_IS_UNSIGNED +#ifndef HAVE_STDDEF_H +#define HAVE_STDDEF_H +#endif +#ifndef HAVE_STDLIB_H +#define HAVE_STDLIB_H +#endif +#undef NEED_BSD_STRINGS +#undef NEED_SYS_TYPES_H +#undef NEED_FAR_POINTERS +#undef NEED_SHORT_EXTERNAL_NAMES +/* Define this if you get warnings about undefined structures. */ +#undef INCOMPLETE_TYPES_BROKEN + + +#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__MINGW32__)) +/* Define "boolean" as unsigned char, not int, per Windows custom */ +/* don't conflict if rpcndr.h already read; Note that the w32api headers + used by Cygwin and Mingw do not define "boolean", so jmorecfg.h + handles it later. */ +#ifndef __RPCNDR_H__ +typedef unsigned char boolean; +#endif +#define HAVE_BOOLEAN /* prevent jmorecfg.h from redefining it */ +#endif + +#ifdef JPEG_INTERNALS + +#undef RIGHT_SHIFT_IS_UNSIGNED +#define INLINE +/* These are for configuring the JPEG memory manager. */ +#undef DEFAULT_MAX_MEM +#undef NO_MKTEMP + +#endif /* JPEG_INTERNALS */ + +#ifdef JPEG_CJPEG_DJPEG + +#define BMP_SUPPORTED /* BMP image file format */ +#define GIF_SUPPORTED /* GIF image file format */ +#define PPM_SUPPORTED /* PBMPLUS PPM/PGM image file format */ +#undef RLE_SUPPORTED /* Utah RLE image file format */ +#define TARGA_SUPPORTED /* Targa image file format */ + +#undef TWO_FILE_COMMANDLINE +#undef NEED_SIGNAL_CATCHER +#undef DONT_USE_B_MODE + +/* Define this if you want percent-done progress reports from cjpeg/djpeg. */ +#undef PROGRESS_REPORT + +#endif /* JPEG_CJPEG_DJPEG */ + + +/* names mangling */ + +#include "@BITS_TYPE_JPEG_MANGLE_NAME@" + +#if defined(__BORLANDC__) +#pragma warn -8004 /* Disable "foo is assigned a value that is never used." */ +#endif diff --git a/src/gdcmjpeg/jcparam.c b/src/gdcmjpeg/jcparam.c new file mode 100644 index 00000000..1f3d0022 --- /dev/null +++ b/src/gdcmjpeg/jcparam.c @@ -0,0 +1,687 @@ +/* + * jcparam.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains optional default-setting code for the JPEG compressor. + * Applications do not have to use this file, but those that don't use it + * must know a lot more about the innards of the JPEG code. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Quantization table setup routines + */ + +GLOBAL(void) +jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl, + const unsigned int *basic_table, + int scale_factor, boolean force_baseline) +/* Define a quantization table equal to the basic_table times + * a scale factor (given as a percentage). + * If force_baseline is TRUE, the computed quantization table entries + * are limited to 1..255 for JPEG baseline compatibility. + */ +{ + JQUANT_TBL ** qtblptr; + int i; + long temp; + + /* Safety check to ensure start_compress not called yet. */ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + if (which_tbl < 0 || which_tbl >= NUM_QUANT_TBLS) + ERREXIT1(cinfo, JERR_DQT_INDEX, which_tbl); + + qtblptr = & cinfo->quant_tbl_ptrs[which_tbl]; + + if (*qtblptr == NULL) + *qtblptr = jpeg_alloc_quant_table((j_common_ptr) cinfo); + + for (i = 0; i < DCTSIZE2; i++) { + temp = ((long) basic_table[i] * scale_factor + 50L) / 100L; + /* limit the values to the valid range */ + if (temp <= 0L) temp = 1L; + if (temp > 32767L) temp = 32767L; /* max quantizer needed for 12 bits */ + if (force_baseline && temp > 255L) + temp = 255L; /* limit to baseline range if requested */ + (*qtblptr)->quantval[i] = (UINT16) temp; + } + + /* Initialize sent_table FALSE so table will be written to JPEG file. */ + (*qtblptr)->sent_table = FALSE; +} + + +GLOBAL(void) +jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor, + boolean force_baseline) +/* Set or change the 'quality' (quantization) setting, using default tables + * and a straight percentage-scaling quality scale. In most cases it's better + * to use jpeg_set_quality (below); this entry point is provided for + * applications that insist on a linear percentage scaling. + */ +{ + /* These are the sample quantization tables given in JPEG spec section K.1. + * The spec says that the values given produce "good" quality, and + * when divided by 2, "very good" quality. + */ + static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = { + 16, 11, 10, 16, 24, 40, 51, 61, + 12, 12, 14, 19, 26, 58, 60, 55, + 14, 13, 16, 24, 40, 57, 69, 56, + 14, 17, 22, 29, 51, 87, 80, 62, + 18, 22, 37, 56, 68, 109, 103, 77, + 24, 35, 55, 64, 81, 104, 113, 92, + 49, 64, 78, 87, 103, 121, 120, 101, + 72, 92, 95, 98, 112, 100, 103, 99 + }; + static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = { + 17, 18, 24, 47, 99, 99, 99, 99, + 18, 21, 26, 66, 99, 99, 99, 99, + 24, 26, 56, 99, 99, 99, 99, 99, + 47, 66, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99 + }; + + /* Set up two quantization tables using the specified scaling */ + jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl, + scale_factor, force_baseline); + jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl, + scale_factor, force_baseline); +} + + +GLOBAL(int) +jpeg_quality_scaling (int quality) +/* Convert a user-specified quality rating to a percentage scaling factor + * for an underlying quantization table, using our recommended scaling curve. + * The input 'quality' factor should be 0 (terrible) to 100 (very good). + */ +{ + /* Safety limit on quality factor. Convert 0 to 1 to avoid zero divide. */ + if (quality <= 0) quality = 1; + if (quality > 100) quality = 100; + + /* The basic table is used as-is (scaling 100) for a quality of 50. + * Qualities 50..100 are converted to scaling percentage 200 - 2*Q; + * note that at Q=100 the scaling is 0, which will cause jpeg_add_quant_table + * to make all the table entries 1 (hence, minimum quantization loss). + * Qualities 1..50 are converted to scaling percentage 5000/Q. + */ + if (quality < 50) + quality = 5000 / quality; + else + quality = 200 - quality*2; + + return quality; +} + + +GLOBAL(void) +jpeg_set_quality (j_compress_ptr cinfo, int quality, boolean force_baseline) +/* Set or change the 'quality' (quantization) setting, using default tables. + * This is the standard quality-adjusting entry point for typical user + * interfaces; only those who want detailed control over quantization tables + * would use the preceding three routines directly. + */ +{ + /* Convert user 0-100 rating to percentage scaling */ + quality = jpeg_quality_scaling(quality); + + /* Set up standard quality tables */ + jpeg_set_linear_quality(cinfo, quality, force_baseline); +} + + +/* + * Huffman table setup routines + */ + +LOCAL(void) +add_huff_table (j_compress_ptr cinfo, + JHUFF_TBL **htblptr, const UINT8 *bits, const UINT8 *val) +/* Define a Huffman table */ +{ + int nsymbols, len; + + if (*htblptr == NULL) + *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); + + /* Copy the number-of-symbols-of-each-code-length counts */ + MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits)); + + /* Validate the counts. We do this here mainly so we can copy the right + * number of symbols from the val[] array, without risking marching off + * the end of memory. jchuff.c will do a more thorough test later. + */ + nsymbols = 0; + for (len = 1; len <= 16; len++) + nsymbols += bits[len]; + if (nsymbols < 1 || nsymbols > 256) + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + + MEMCOPY((*htblptr)->huffval, val, nsymbols * SIZEOF(UINT8)); + + /* Initialize sent_table FALSE so table will be written to JPEG file. */ + (*htblptr)->sent_table = FALSE; +} + + +LOCAL(void) +std_huff_tables (j_compress_ptr cinfo) +/* Set up the standard Huffman tables (cf. JPEG standard section K.3) */ +/* IMPORTANT: these are only valid for 8-bit data precision! */ +{ + static const UINT8 bits_dc_luminance[17] = + { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 }; + static const UINT8 val_dc_luminance[] = + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 }; + + static const UINT8 bits_dc_chrominance[17] = + { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 }; + static const UINT8 val_dc_chrominance[] = + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 }; + + static const UINT8 bits_ac_luminance[17] = + { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d }; + static const UINT8 val_ac_luminance[] = + { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, + 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, + 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, + 0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0, + 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, + 0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, + 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, + 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, + 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, + 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, + 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, + 0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, + 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, + 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, + 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, + 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, + 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, + 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2, + 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, + 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, + 0xf9, 0xfa }; + + static const UINT8 bits_ac_chrominance[17] = + { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 }; + static const UINT8 val_ac_chrominance[] = + { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, + 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, + 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, + 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, + 0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, + 0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, + 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, + 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, + 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, + 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, + 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, + 0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, + 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, + 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, + 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, + 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, + 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, + 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, + 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, + 0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, + 0xf9, 0xfa }; + + add_huff_table(cinfo, &cinfo->dc_huff_tbl_ptrs[0], + bits_dc_luminance, val_dc_luminance); + add_huff_table(cinfo, &cinfo->ac_huff_tbl_ptrs[0], + bits_ac_luminance, val_ac_luminance); + add_huff_table(cinfo, &cinfo->dc_huff_tbl_ptrs[1], + bits_dc_chrominance, val_dc_chrominance); + add_huff_table(cinfo, &cinfo->ac_huff_tbl_ptrs[1], + bits_ac_chrominance, val_ac_chrominance); +} + + +/* + * Default parameter setup for compression. + * + * Applications that don't choose to use this routine must do their + * own setup of all these parameters. Alternately, you can call this + * to establish defaults and then alter parameters selectively. This + * is the recommended approach since, if we add any new parameters, + * your code will still work (they'll be set to reasonable defaults). + */ + +GLOBAL(void) +jpeg_set_defaults (j_compress_ptr cinfo) +{ + int i; + + /* Safety check to ensure start_compress not called yet. */ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + /* Allocate comp_info array large enough for maximum component count. + * Array is made permanent in case application wants to compress + * multiple images at same param settings. + */ + if (cinfo->comp_info == NULL) + cinfo->comp_info = (jpeg_component_info *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + MAX_COMPONENTS * SIZEOF(jpeg_component_info)); + + /* Initialize everything not dependent on the color space */ + + cinfo->lossless = FALSE; + cinfo->data_precision = BITS_IN_JSAMPLE; + /* Set up two quantization tables using default quality of 75 */ + jpeg_set_quality(cinfo, 75, TRUE); + /* Set up two Huffman tables */ + std_huff_tables(cinfo); + + /* Initialize default arithmetic coding conditioning */ + for (i = 0; i < NUM_ARITH_TBLS; i++) { + cinfo->arith_dc_L[i] = 0; + cinfo->arith_dc_U[i] = 1; + cinfo->arith_ac_K[i] = 5; + } + + /* Default is no multiple-scan output */ + cinfo->scan_info = NULL; + cinfo->num_scans = 0; + + /* Expect normal source image, not raw downsampled data */ + cinfo->raw_data_in = FALSE; + + /* Use Huffman coding, not arithmetic coding, by default */ + cinfo->arith_code = FALSE; + + /* By default, don't do extra passes to optimize entropy coding */ + cinfo->optimize_coding = FALSE; + /* The standard Huffman tables are only valid for 8-bit data precision. + * If the precision is higher, force optimization on so that usable + * tables will be computed. This test can be removed if default tables + * are supplied that are valid for the desired precision. + */ + if (cinfo->data_precision > 8) + cinfo->optimize_coding = TRUE; + + /* By default, use the simpler non-cosited sampling alignment */ + cinfo->CCIR601_sampling = FALSE; + + /* No input smoothing */ + cinfo->smoothing_factor = 0; + + /* DCT algorithm preference */ + cinfo->dct_method = JDCT_DEFAULT; + + /* No restart markers */ + cinfo->restart_interval = 0; + cinfo->restart_in_rows = 0; + + /* Fill in default JFIF marker parameters. Note that whether the marker + * will actually be written is determined by jpeg_set_colorspace. + * + * By default, the library emits JFIF version code 1.01. + * An application that wants to emit JFIF 1.02 extension markers should set + * JFIF_minor_version to 2. We could probably get away with just defaulting + * to 1.02, but there may still be some decoders in use that will complain + * about that; saying 1.01 should minimize compatibility problems. + */ + cinfo->JFIF_major_version = 1; /* Default JFIF version = 1.01 */ + cinfo->JFIF_minor_version = 1; + cinfo->density_unit = 0; /* Pixel size is unknown by default */ + cinfo->X_density = 1; /* Pixel aspect ratio is square by default */ + cinfo->Y_density = 1; + + /* Choose JPEG colorspace based on input space, set defaults accordingly */ + + jpeg_default_colorspace(cinfo); +} + + +/* + * Select an appropriate JPEG colorspace for in_color_space. + */ + +GLOBAL(void) +jpeg_default_colorspace (j_compress_ptr cinfo) +{ + if (cinfo->lossless) + jpeg_set_colorspace(cinfo, cinfo->in_color_space); + else { /* lossy */ + switch (cinfo->in_color_space) { + case JCS_GRAYSCALE: + jpeg_set_colorspace(cinfo, JCS_GRAYSCALE); + break; + case JCS_RGB: + jpeg_set_colorspace(cinfo, JCS_YCbCr); + break; + case JCS_YCbCr: + jpeg_set_colorspace(cinfo, JCS_YCbCr); + break; + case JCS_CMYK: + jpeg_set_colorspace(cinfo, JCS_CMYK); /* By default, no translation */ + break; + case JCS_YCCK: + jpeg_set_colorspace(cinfo, JCS_YCCK); + break; + case JCS_UNKNOWN: + jpeg_set_colorspace(cinfo, JCS_UNKNOWN); + break; + default: + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); + } + } +} + + +/* + * Set the JPEG colorspace, and choose colorspace-dependent default values. + */ + +GLOBAL(void) +jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace) +{ + jpeg_component_info * compptr; + int ci; + +#define SET_COMP(index,id,hsamp,vsamp,quant,dctbl,actbl) \ + (compptr = &cinfo->comp_info[index], \ + compptr->component_id = (id), \ + compptr->h_samp_factor = (hsamp), \ + compptr->v_samp_factor = (vsamp), \ + compptr->quant_tbl_no = (quant), \ + compptr->dc_tbl_no = (dctbl), \ + compptr->ac_tbl_no = (actbl) ) + + /* Safety check to ensure start_compress not called yet. */ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + /* For all colorspaces, we use Q and Huff tables 0 for luminance components, + * tables 1 for chrominance components. + */ + + cinfo->jpeg_color_space = colorspace; + + cinfo->write_JFIF_header = FALSE; /* No marker for non-JFIF colorspaces */ + cinfo->write_Adobe_marker = FALSE; /* write no Adobe marker by default */ + + switch (colorspace) { + case JCS_GRAYSCALE: + cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */ + cinfo->num_components = 1; + /* JFIF specifies component ID 1 */ + SET_COMP(0, 1, 1,1, 0, 0,0); + break; + case JCS_RGB: + cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag RGB */ + cinfo->num_components = 3; + SET_COMP(0, 0x52 /* 'R' */, 1,1, 0, 0,0); + SET_COMP(1, 0x47 /* 'G' */, 1,1, 0, 0,0); + SET_COMP(2, 0x42 /* 'B' */, 1,1, 0, 0,0); + break; + case JCS_YCbCr: + cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */ + cinfo->num_components = 3; + /* JFIF specifies component IDs 1,2,3 */ + if (cinfo->lossless) { + SET_COMP(0, 1, 1,1, 0, 0,0); + SET_COMP(1, 2, 1,1, 1, 1,1); + SET_COMP(2, 3, 1,1, 1, 1,1); + } else { /* lossy */ + /* We default to 2x2 subsamples of chrominance */ + SET_COMP(0, 1, 2,2, 0, 0,0); + SET_COMP(1, 2, 1,1, 1, 1,1); + SET_COMP(2, 3, 1,1, 1, 1,1); + } + break; + case JCS_CMYK: + cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag CMYK */ + cinfo->num_components = 4; + SET_COMP(0, 0x43 /* 'C' */, 1,1, 0, 0,0); + SET_COMP(1, 0x4D /* 'M' */, 1,1, 0, 0,0); + SET_COMP(2, 0x59 /* 'Y' */, 1,1, 0, 0,0); + SET_COMP(3, 0x4B /* 'K' */, 1,1, 0, 0,0); + break; + case JCS_YCCK: + cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag YCCK */ + cinfo->num_components = 4; + if (cinfo->lossless) { + SET_COMP(0, 1, 1,1, 0, 0,0); + SET_COMP(1, 2, 1,1, 1, 1,1); + SET_COMP(2, 3, 1,1, 1, 1,1); + SET_COMP(3, 4, 1,1, 0, 0,0); + } else { /* lossy */ + SET_COMP(0, 1, 2,2, 0, 0,0); + SET_COMP(1, 2, 1,1, 1, 1,1); + SET_COMP(2, 3, 1,1, 1, 1,1); + SET_COMP(3, 4, 2,2, 0, 0,0); + } + break; + case JCS_UNKNOWN: + cinfo->num_components = cinfo->input_components; + if (cinfo->num_components < 1 || cinfo->num_components > MAX_COMPONENTS) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, + MAX_COMPONENTS); + for (ci = 0; ci < cinfo->num_components; ci++) { + SET_COMP(ci, ci, 1,1, 0, 0,0); + } + break; + default: + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + } +} + + +#ifdef C_PROGRESSIVE_SUPPORTED + +LOCAL(jpeg_scan_info *) +fill_scans (jpeg_scan_info * scanptr, int ncomps, + int Ss, int Se, int Ah, int Al) +/* Support routine: generate one scan for each component */ +{ + int ci; + + for (ci = 0; ci < ncomps; ci++) { + scanptr->comps_in_scan = 1; + scanptr->component_index[0] = ci; + scanptr->Ss = Ss; + scanptr->Se = Se; + scanptr->Ah = Ah; + scanptr->Al = Al; + scanptr++; + } + return scanptr; +} + + +LOCAL(jpeg_scan_info *) +fill_a_scan (jpeg_scan_info * scanptr, int ci, + int Ss, int Se, int Ah, int Al) +/* Support routine: generate one scan for specified component */ +{ + scanptr->comps_in_scan = 1; + scanptr->component_index[0] = ci; + scanptr->Ss = Ss; + scanptr->Se = Se; + scanptr->Ah = Ah; + scanptr->Al = Al; + scanptr++; + return scanptr; +} + +LOCAL(jpeg_scan_info *) +fill_dc_scans (jpeg_scan_info * scanptr, int ncomps, int Ah, int Al) +/* Support routine: generate interleaved DC scan if possible, else N scans */ +{ + int ci; + + if (ncomps <= MAX_COMPS_IN_SCAN) { + /* Single interleaved DC scan */ + scanptr->comps_in_scan = ncomps; + for (ci = 0; ci < ncomps; ci++) + scanptr->component_index[ci] = ci; + scanptr->Ss = scanptr->Se = 0; + scanptr->Ah = Ah; + scanptr->Al = Al; + scanptr++; + } else { + /* Noninterleaved DC scan for each component */ + scanptr = fill_scans(scanptr, ncomps, 0, 0, Ah, Al); + } + return scanptr; +} + + +/* + * Create a recommended progressive-JPEG script. + * cinfo->num_components and cinfo->jpeg_color_space must be correct. + */ + +GLOBAL(void) +jpeg_simple_progression (j_compress_ptr cinfo) +{ + int ncomps = cinfo->num_components; + int nscans; + jpeg_scan_info * scanptr; + + /* Safety check to ensure start_compress not called yet. */ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + /* Figure space needed for script. Calculation must match code below! */ + if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) { + /* Custom script for YCbCr color images. */ + nscans = 10; + } else { + /* All-purpose script for other color spaces. */ + if (ncomps > MAX_COMPS_IN_SCAN) + nscans = 6 * ncomps; /* 2 DC + 4 AC scans per component */ + else + nscans = 2 + 4 * ncomps; /* 2 DC scans; 4 AC scans per component */ + } + + /* Allocate space for script. + * We need to put it in the permanent pool in case the application performs + * multiple compressions without changing the settings. To avoid a memory + * leak if jpeg_simple_progression is called repeatedly for the same JPEG + * object, we try to re-use previously allocated space, and we allocate + * enough space to handle YCbCr even if initially asked for grayscale. + */ + if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) { + cinfo->script_space_size = MAX(nscans, 10); + cinfo->script_space = (jpeg_scan_info *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + cinfo->script_space_size * SIZEOF(jpeg_scan_info)); + } + scanptr = cinfo->script_space; + cinfo->scan_info = scanptr; + cinfo->num_scans = nscans; + + if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) { + /* Custom script for YCbCr color images. */ + /* Initial DC scan */ + scanptr = fill_dc_scans(scanptr, ncomps, 0, 1); + /* Initial AC scan: get some luma data out in a hurry */ + scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2); + /* Chroma data is too small to be worth expending many scans on */ + scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1); + scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1); + /* Complete spectral selection for luma AC */ + scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2); + /* Refine next bit of luma AC */ + scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1); + /* Finish DC successive approximation */ + scanptr = fill_dc_scans(scanptr, ncomps, 1, 0); + /* Finish AC successive approximation */ + scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0); + scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0); + /* Luma bottom bit comes last since it's usually largest scan */ + scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0); + } else { + /* All-purpose script for other color spaces. */ + /* Successive approximation first pass */ + scanptr = fill_dc_scans(scanptr, ncomps, 0, 1); + scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2); + scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2); + /* Successive approximation second pass */ + scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1); + /* Successive approximation final pass */ + scanptr = fill_dc_scans(scanptr, ncomps, 1, 0); + scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0); + } +} + +#endif /* C_PROGRESSIVE_SUPPORTED */ + + +#ifdef C_LOSSLESS_SUPPORTED + +/* + * Create a single-entry lossless-JPEG script containing all components. + * cinfo->num_components must be correct. + */ + +GLOBAL(void) +jpeg_simple_lossless (j_compress_ptr cinfo, int predictor, int point_transform) +{ + int ncomps = cinfo->num_components; + int nscans = 1; + int ci; + jpeg_scan_info * scanptr; + + /* Safety check to ensure start_compress not called yet. */ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + cinfo->lossless = TRUE; + + /* Set jpeg_color_space. */ + jpeg_default_colorspace(cinfo); + + /* Check to ensure that all components will fit in one scan. */ + if (cinfo->num_components > MAX_COMPS_IN_SCAN) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, + MAX_COMPS_IN_SCAN); + + /* Allocate space for script. + * We need to put it in the permanent pool in case the application performs + * multiple compressions without changing the settings. To avoid a memory + * leak if jpeg_simple_lossless is called repeatedly for the same JPEG + * object, we try to re-use previously allocated space. + */ + if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) { + cinfo->script_space_size = nscans; + cinfo->script_space = (jpeg_scan_info *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + cinfo->script_space_size * SIZEOF(jpeg_scan_info)); + } + scanptr = cinfo->script_space; + cinfo->scan_info = scanptr; + cinfo->num_scans = nscans; + + /* Fill the script. */ + scanptr->comps_in_scan = ncomps; + for (ci = 0; ci < ncomps; ci++) + scanptr->component_index[ci] = ci; + scanptr->Ss = predictor; + scanptr->Se = 0; + scanptr->Ah = 0; + scanptr->Al = point_transform; +} + +#endif /* C_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jcphuff.c b/src/gdcmjpeg/jcphuff.c new file mode 100644 index 00000000..63b9e461 --- /dev/null +++ b/src/gdcmjpeg/jcphuff.c @@ -0,0 +1,848 @@ +/* + * jcphuff.c + * + * Copyright (C) 1995-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy encoding routines for progressive JPEG. + * + * We do not support output suspension in this module, since the library + * currently does not allow multiple-scan files to be written with output + * suspension. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ +#include "jchuff.h" /* Declarations shared with jc*huff.c */ + +#ifdef C_PROGRESSIVE_SUPPORTED + +/* Expanded entropy encoder object for progressive Huffman encoding. */ + +typedef struct { + /* Mode flag: TRUE for optimization, FALSE for actual data output */ + boolean gather_statistics; + + /* Bit-level coding status. + * next_output_byte/free_in_buffer are local copies of cinfo->dest fields. + */ + JOCTET * next_output_byte; /* => next byte to write in buffer */ + size_t free_in_buffer; /* # of byte spaces remaining in buffer */ + INT32 put_buffer; /* current bit-accumulation buffer */ + int put_bits; /* # of bits now in it */ + j_compress_ptr cinfo; /* link to cinfo (needed for dump_buffer) */ + + /* Coding status for DC components */ + int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */ + + /* Coding status for AC components */ + int ac_tbl_no; /* the table number of the single component */ + unsigned int EOBRUN; /* run length of EOBs */ + unsigned int BE; /* # of buffered correction bits before MCU */ + char * bit_buffer; /* buffer for correction bits (1 per char) */ + /* packing correction bits tightly would save some space but cost time... */ + + unsigned int restarts_to_go; /* MCUs left in this restart interval */ + int next_restart_num; /* next restart number to write (0-7) */ + + /* Pointers to derived tables (these workspaces have image lifespan). + * Since any one scan codes only DC or only AC, we only need one set + * of tables, not one for DC and one for AC. + */ + c_derived_tbl * derived_tbls[NUM_HUFF_TBLS]; + + /* Statistics tables for optimization; again, one set is enough */ + long * count_ptrs[NUM_HUFF_TBLS]; +} phuff_entropy_encoder; + +typedef phuff_entropy_encoder * phuff_entropy_ptr; + +/* MAX_CORR_BITS is the number of bits the AC refinement correction-bit + * buffer can hold. Larger sizes may slightly improve compression, but + * 1000 is already well into the realm of overkill. + * The minimum safe size is 64 bits. + */ + +#define MAX_CORR_BITS 1000 /* Max # of correction bits I can buffer */ + +/* IRIGHT_SHIFT is like RIGHT_SHIFT, but works on int rather than INT32. + * We assume that int right shift is unsigned if INT32 right shift is, + * which should be safe. + */ + +#ifdef RIGHT_SHIFT_IS_UNSIGNED +#define ISHIFT_TEMPS int ishift_temp; +#define IRIGHT_SHIFT(x,shft) \ + ((ishift_temp = (x)) < 0 ? \ + (ishift_temp >> (shft)) | ((~0) << (16-(shft))) : \ + (ishift_temp >> (shft))) +#else +#define ISHIFT_TEMPS +#define IRIGHT_SHIFT(x,shft) ((x) >> (shft)) +#endif + +/* Forward declarations */ +METHODDEF(boolean) encode_mcu_DC_first JPP((j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(boolean) encode_mcu_AC_first JPP((j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(boolean) encode_mcu_DC_refine JPP((j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(boolean) encode_mcu_AC_refine JPP((j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(void) finish_pass_phuff JPP((j_compress_ptr cinfo)); +METHODDEF(void) finish_pass_gather_phuff JPP((j_compress_ptr cinfo)); + + +/* + * Initialize for a Huffman-compressed scan using progressive JPEG. + */ + +METHODDEF(void) +start_pass_phuff (j_compress_ptr cinfo, boolean gather_statistics) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + boolean is_DC_band; + int ci, tbl; + jpeg_component_info * compptr; + + entropy->cinfo = cinfo; + entropy->gather_statistics = gather_statistics; + + is_DC_band = (cinfo->Ss == 0); + + /* We assume jcmaster.c already validated the scan parameters. */ + + /* Select execution routines */ + if (cinfo->Ah == 0) { + if (is_DC_band) + lossyc->entropy_encode_mcu = encode_mcu_DC_first; + else + lossyc->entropy_encode_mcu = encode_mcu_AC_first; + } else { + if (is_DC_band) + lossyc->entropy_encode_mcu = encode_mcu_DC_refine; + else { + lossyc->entropy_encode_mcu = encode_mcu_AC_refine; + /* AC refinement needs a correction bit buffer */ + if (entropy->bit_buffer == NULL) + entropy->bit_buffer = (char *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + MAX_CORR_BITS * SIZEOF(char)); + } + } + if (gather_statistics) + lossyc->pub.entropy_finish_pass = finish_pass_gather_phuff; + else + lossyc->pub.entropy_finish_pass = finish_pass_phuff; + + /* Only DC coefficients may be interleaved, so cinfo->comps_in_scan = 1 + * for AC coefficients. + */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + /* Initialize DC predictions to 0 */ + entropy->last_dc_val[ci] = 0; + /* Get table index */ + if (is_DC_band) { + if (cinfo->Ah != 0) /* DC refinement needs no table */ + continue; + tbl = compptr->dc_tbl_no; + } else { + entropy->ac_tbl_no = tbl = compptr->ac_tbl_no; + } + if (gather_statistics) { + /* Check for invalid table index */ + /* (make_c_derived_tbl does this in the other path) */ + if (tbl < 0 || tbl >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl); + /* Allocate and zero the statistics tables */ + /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */ + if (entropy->count_ptrs[tbl] == NULL) + entropy->count_ptrs[tbl] = (long *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + 257 * SIZEOF(long)); + MEMZERO(entropy->count_ptrs[tbl], 257 * SIZEOF(long)); + } else { + /* Compute derived values for Huffman table */ + /* We may do this more than once for a table, but it's not expensive */ + jpeg_make_c_derived_tbl(cinfo, is_DC_band, tbl, + & entropy->derived_tbls[tbl]); + } + } + + /* Initialize AC stuff */ + entropy->EOBRUN = 0; + entropy->BE = 0; + + /* Initialize bit buffer to empty */ + entropy->put_buffer = 0; + entropy->put_bits = 0; + + /* Initialize restart stuff */ + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num = 0; +} + + +/* Outputting bytes to the file. + * NB: these must be called only when actually outputting, + * that is, entropy->gather_statistics == FALSE. + */ + +/* Emit a byte */ +#define emit_byte(entropy,val) \ + { *(entropy)->next_output_byte++ = (JOCTET) (val); \ + if (--(entropy)->free_in_buffer == 0) \ + dump_buffer(entropy); } + + +LOCAL(void) +dump_buffer (phuff_entropy_ptr entropy) +/* Empty the output buffer; we do not support suspension in this module. */ +{ + struct jpeg_destination_mgr * dest = entropy->cinfo->dest; + + if (! (*dest->empty_output_buffer) (entropy->cinfo)) + ERREXIT(entropy->cinfo, JERR_CANT_SUSPEND); + /* After a successful buffer dump, must reset buffer pointers */ + entropy->next_output_byte = dest->next_output_byte; + entropy->free_in_buffer = dest->free_in_buffer; +} + + +/* Outputting bits to the file */ + +/* Only the right 24 bits of put_buffer are used; the valid bits are + * left-justified in this part. At most 16 bits can be passed to emit_bits + * in one call, and we never retain more than 7 bits in put_buffer + * between calls, so 24 bits are sufficient. + */ + +INLINE +LOCAL(void) +emit_bits (phuff_entropy_ptr entropy, unsigned int code, int size) +/* Emit some bits, unless we are in gather mode */ +{ + /* This routine is heavily used, so it's worth coding tightly. */ + register INT32 put_buffer = (INT32) code; + register int put_bits = entropy->put_bits; + + /* if size is 0, caller used an invalid Huffman table entry */ + if (size == 0) + ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE); + + if (entropy->gather_statistics) + return; /* do nothing if we're only getting stats */ + + put_buffer &= (((INT32) 1)<put_buffer; /* and merge with old buffer contents */ + + while (put_bits >= 8) { + int c = (int) ((put_buffer >> 16) & 0xFF); + + emit_byte(entropy, c); + if (c == 0xFF) { /* need to stuff a zero byte? */ + emit_byte(entropy, 0); + } + put_buffer <<= 8; + put_bits -= 8; + } + + entropy->put_buffer = put_buffer; /* update variables */ + entropy->put_bits = put_bits; +} + + +LOCAL(void) +flush_bits (phuff_entropy_ptr entropy) +{ + emit_bits(entropy, 0x7F, 7); /* fill any partial byte with ones */ + entropy->put_buffer = 0; /* and reset bit-buffer to empty */ + entropy->put_bits = 0; +} + + +/* + * Emit (or just count) a Huffman symbol. + */ + +INLINE +LOCAL(void) +emit_symbol (phuff_entropy_ptr entropy, int tbl_no, int symbol) +{ + if (entropy->gather_statistics) + entropy->count_ptrs[tbl_no][symbol]++; + else { + c_derived_tbl * tbl = entropy->derived_tbls[tbl_no]; + emit_bits(entropy, tbl->ehufco[symbol], tbl->ehufsi[symbol]); + } +} + + +/* + * Emit bits from a correction bit buffer. + */ + +LOCAL(void) +emit_buffered_bits (phuff_entropy_ptr entropy, char * bufstart, + unsigned int nbits) +{ + if (entropy->gather_statistics) + return; /* no real work */ + + while (nbits > 0) { + emit_bits(entropy, (unsigned int) (*bufstart), 1); + bufstart++; + nbits--; + } +} + + +/* + * Emit any pending EOBRUN symbol. + */ + +LOCAL(void) +emit_eobrun (phuff_entropy_ptr entropy) +{ + register int temp, nbits; + + if (entropy->EOBRUN > 0) { /* if there is any pending EOBRUN */ + temp = entropy->EOBRUN; + nbits = 0; + while ((temp >>= 1)) + nbits++; + /* safety check: shouldn't happen given limited correction-bit buffer */ + if (nbits > 14) + ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE); + + emit_symbol(entropy, entropy->ac_tbl_no, nbits << 4); + if (nbits) + emit_bits(entropy, entropy->EOBRUN, nbits); + + entropy->EOBRUN = 0; + + /* Emit any buffered correction bits */ + emit_buffered_bits(entropy, entropy->bit_buffer, entropy->BE); + entropy->BE = 0; + } +} + + +/* + * Emit a restart marker & resynchronize predictions. + */ + +LOCAL(void) +emit_restart (phuff_entropy_ptr entropy, int restart_num) +{ + int ci; + + emit_eobrun(entropy); + + if (! entropy->gather_statistics) { + flush_bits(entropy); + emit_byte(entropy, 0xFF); + emit_byte(entropy, JPEG_RST0 + restart_num); + } + + if (entropy->cinfo->Ss == 0) { + /* Re-initialize DC predictions to 0 */ + for (ci = 0; ci < entropy->cinfo->comps_in_scan; ci++) + entropy->last_dc_val[ci] = 0; + } else { + /* Re-initialize all AC-related fields to 0 */ + entropy->EOBRUN = 0; + entropy->BE = 0; + } +} + + +/* + * MCU encoding for DC initial scan (either spectral selection, + * or first pass of successive approximation). + */ + +METHODDEF(boolean) +encode_mcu_DC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + register int temp, temp2; + register int nbits; + int blkn, ci; + int Al = cinfo->Al; + JBLOCKROW block; + jpeg_component_info * compptr; + ISHIFT_TEMPS + + entropy->next_output_byte = cinfo->dest->next_output_byte; + entropy->free_in_buffer = cinfo->dest->free_in_buffer; + + /* Emit restart marker if needed */ + if (cinfo->restart_interval) + if (entropy->restarts_to_go == 0) + emit_restart(entropy, entropy->next_restart_num); + + /* Encode the MCU data blocks */ + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + block = MCU_data[blkn]; + ci = cinfo->MCU_membership[blkn]; + compptr = cinfo->cur_comp_info[ci]; + + /* Compute the DC value after the required point transform by Al. + * This is simply an arithmetic right shift. + */ + temp2 = IRIGHT_SHIFT((int) ((*block)[0]), Al); + + /* DC differences are figured on the point-transformed values. */ + temp = temp2 - entropy->last_dc_val[ci]; + entropy->last_dc_val[ci] = temp2; + + /* Encode the DC coefficient difference per section G.1.2.1 */ + temp2 = temp; + if (temp < 0) { + temp = -temp; /* temp is abs value of input */ + /* For a negative input, want temp2 = bitwise complement of abs(input) */ + /* This code assumes we are on a two's complement machine */ + temp2--; + } + + /* Find the number of bits needed for the magnitude of the coefficient */ + nbits = 0; + while (temp) { + nbits++; + temp >>= 1; + } + /* Check for out-of-range coefficient values. + * Since we're encoding a difference, the range limit is twice as much. + */ + if (nbits > MAX_COEF_BITS+1) + ERREXIT(cinfo, JERR_BAD_DCT_COEF); + + /* Count/emit the Huffman-coded symbol for the number of bits */ + emit_symbol(entropy, compptr->dc_tbl_no, nbits); + + /* Emit that number of bits of the value, if positive, */ + /* or the complement of its magnitude, if negative. */ + if (nbits) /* emit_bits rejects calls with size 0 */ + emit_bits(entropy, (unsigned int) temp2, nbits); + } + + cinfo->dest->next_output_byte = entropy->next_output_byte; + cinfo->dest->free_in_buffer = entropy->free_in_buffer; + + /* Update restart-interval state too */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num++; + entropy->next_restart_num &= 7; + } + entropy->restarts_to_go--; + } + + return TRUE; +} + + +/* + * MCU encoding for AC initial scan (either spectral selection, + * or first pass of successive approximation). + */ + +METHODDEF(boolean) +encode_mcu_AC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + register int temp, temp2; + register int nbits; + register int r, k; + int Se = cinfo->Se; + int Al = cinfo->Al; + JBLOCKROW block; + + entropy->next_output_byte = cinfo->dest->next_output_byte; + entropy->free_in_buffer = cinfo->dest->free_in_buffer; + + /* Emit restart marker if needed */ + if (cinfo->restart_interval) + if (entropy->restarts_to_go == 0) + emit_restart(entropy, entropy->next_restart_num); + + /* Encode the MCU data block */ + block = MCU_data[0]; + + /* Encode the AC coefficients per section G.1.2.2, fig. G.3 */ + + r = 0; /* r = run length of zeros */ + + for (k = cinfo->Ss; k <= Se; k++) { + if ((temp = (*block)[jpeg_natural_order[k]]) == 0) { + r++; + continue; + } + /* We must apply the point transform by Al. For AC coefficients this + * is an integer division with rounding towards 0. To do this portably + * in C, we shift after obtaining the absolute value; so the code is + * interwoven with finding the abs value (temp) and output bits (temp2). + */ + if (temp < 0) { + temp = -temp; /* temp is abs value of input */ + temp >>= Al; /* apply the point transform */ + /* For a negative coef, want temp2 = bitwise complement of abs(coef) */ + temp2 = ~temp; + } else { + temp >>= Al; /* apply the point transform */ + temp2 = temp; + } + /* Watch out for case that nonzero coef is zero after point transform */ + if (temp == 0) { + r++; + continue; + } + + /* Emit any pending EOBRUN */ + if (entropy->EOBRUN > 0) + emit_eobrun(entropy); + /* if run length > 15, must emit special run-length-16 codes (0xF0) */ + while (r > 15) { + emit_symbol(entropy, entropy->ac_tbl_no, 0xF0); + r -= 16; + } + + /* Find the number of bits needed for the magnitude of the coefficient */ + nbits = 1; /* there must be at least one 1 bit */ + while ((temp >>= 1)) + nbits++; + /* Check for out-of-range coefficient values */ + if (nbits > MAX_COEF_BITS) + ERREXIT(cinfo, JERR_BAD_DCT_COEF); + + /* Count/emit Huffman symbol for run length / number of bits */ + emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + nbits); + + /* Emit that number of bits of the value, if positive, */ + /* or the complement of its magnitude, if negative. */ + emit_bits(entropy, (unsigned int) temp2, nbits); + + r = 0; /* reset zero run length */ + } + + if (r > 0) { /* If there are trailing zeroes, */ + entropy->EOBRUN++; /* count an EOB */ + if (entropy->EOBRUN == 0x7FFF) + emit_eobrun(entropy); /* force it out to avoid overflow */ + } + + cinfo->dest->next_output_byte = entropy->next_output_byte; + cinfo->dest->free_in_buffer = entropy->free_in_buffer; + + /* Update restart-interval state too */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num++; + entropy->next_restart_num &= 7; + } + entropy->restarts_to_go--; + } + + return TRUE; +} + + +/* + * MCU encoding for DC successive approximation refinement scan. + * Note: we assume such scans can be multi-component, although the spec + * is not very clear on the point. + */ + +METHODDEF(boolean) +encode_mcu_DC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + register int temp; + int blkn; + int Al = cinfo->Al; + JBLOCKROW block; + + entropy->next_output_byte = cinfo->dest->next_output_byte; + entropy->free_in_buffer = cinfo->dest->free_in_buffer; + + /* Emit restart marker if needed */ + if (cinfo->restart_interval) + if (entropy->restarts_to_go == 0) + emit_restart(entropy, entropy->next_restart_num); + + /* Encode the MCU data blocks */ + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + block = MCU_data[blkn]; + + /* We simply emit the Al'th bit of the DC coefficient value. */ + temp = (*block)[0]; + emit_bits(entropy, (unsigned int) (temp >> Al), 1); + } + + cinfo->dest->next_output_byte = entropy->next_output_byte; + cinfo->dest->free_in_buffer = entropy->free_in_buffer; + + /* Update restart-interval state too */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num++; + entropy->next_restart_num &= 7; + } + entropy->restarts_to_go--; + } + + return TRUE; +} + + +/* + * MCU encoding for AC successive approximation refinement scan. + */ + +METHODDEF(boolean) +encode_mcu_AC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + register int temp; + register int r, k; + int EOB; + char *BR_buffer; + unsigned int BR; + int Se = cinfo->Se; + int Al = cinfo->Al; + JBLOCKROW block; + int absvalues[DCTSIZE2]; + + entropy->next_output_byte = cinfo->dest->next_output_byte; + entropy->free_in_buffer = cinfo->dest->free_in_buffer; + + /* Emit restart marker if needed */ + if (cinfo->restart_interval) + if (entropy->restarts_to_go == 0) + emit_restart(entropy, entropy->next_restart_num); + + /* Encode the MCU data block */ + block = MCU_data[0]; + + /* It is convenient to make a pre-pass to determine the transformed + * coefficients' absolute values and the EOB position. + */ + EOB = 0; + for (k = cinfo->Ss; k <= Se; k++) { + temp = (*block)[jpeg_natural_order[k]]; + /* We must apply the point transform by Al. For AC coefficients this + * is an integer division with rounding towards 0. To do this portably + * in C, we shift after obtaining the absolute value. + */ + if (temp < 0) + temp = -temp; /* temp is abs value of input */ + temp >>= Al; /* apply the point transform */ + absvalues[k] = temp; /* save abs value for main pass */ + if (temp == 1) + EOB = k; /* EOB = index of last newly-nonzero coef */ + } + + /* Encode the AC coefficients per section G.1.2.3, fig. G.7 */ + + r = 0; /* r = run length of zeros */ + BR = 0; /* BR = count of buffered bits added now */ + BR_buffer = entropy->bit_buffer + entropy->BE; /* Append bits to buffer */ + + for (k = cinfo->Ss; k <= Se; k++) { + if ((temp = absvalues[k]) == 0) { + r++; + continue; + } + + /* Emit any required ZRLs, but not if they can be folded into EOB */ + while (r > 15 && k <= EOB) { + /* emit any pending EOBRUN and the BE correction bits */ + emit_eobrun(entropy); + /* Emit ZRL */ + emit_symbol(entropy, entropy->ac_tbl_no, 0xF0); + r -= 16; + /* Emit buffered correction bits that must be associated with ZRL */ + emit_buffered_bits(entropy, BR_buffer, BR); + BR_buffer = entropy->bit_buffer; /* BE bits are gone now */ + BR = 0; + } + + /* If the coef was previously nonzero, it only needs a correction bit. + * NOTE: a straight translation of the spec's figure G.7 would suggest + * that we also need to test r > 15. But if r > 15, we can only get here + * if k > EOB, which implies that this coefficient is not 1. + */ + if (temp > 1) { + /* The correction bit is the next bit of the absolute value. */ + BR_buffer[BR++] = (char) (temp & 1); + continue; + } + + /* Emit any pending EOBRUN and the BE correction bits */ + emit_eobrun(entropy); + + /* Count/emit Huffman symbol for run length / number of bits */ + emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + 1); + + /* Emit output bit for newly-nonzero coef */ + temp = ((*block)[jpeg_natural_order[k]] < 0) ? 0 : 1; + emit_bits(entropy, (unsigned int) temp, 1); + + /* Emit buffered correction bits that must be associated with this code */ + emit_buffered_bits(entropy, BR_buffer, BR); + BR_buffer = entropy->bit_buffer; /* BE bits are gone now */ + BR = 0; + r = 0; /* reset zero run length */ + } + + if (r > 0 || BR > 0) { /* If there are trailing zeroes, */ + entropy->EOBRUN++; /* count an EOB */ + entropy->BE += BR; /* concat my correction bits to older ones */ + /* We force out the EOB if we risk either: + * 1. overflow of the EOB counter; + * 2. overflow of the correction bit buffer during the next MCU. + */ + if (entropy->EOBRUN == 0x7FFF || entropy->BE > (MAX_CORR_BITS-DCTSIZE2+1)) + emit_eobrun(entropy); + } + + cinfo->dest->next_output_byte = entropy->next_output_byte; + cinfo->dest->free_in_buffer = entropy->free_in_buffer; + + /* Update restart-interval state too */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num++; + entropy->next_restart_num &= 7; + } + entropy->restarts_to_go--; + } + + return TRUE; +} + + +/* + * Finish up at the end of a Huffman-compressed progressive scan. + */ + +METHODDEF(void) +finish_pass_phuff (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + + entropy->next_output_byte = cinfo->dest->next_output_byte; + entropy->free_in_buffer = cinfo->dest->free_in_buffer; + + /* Flush out any buffered data */ + emit_eobrun(entropy); + flush_bits(entropy); + + cinfo->dest->next_output_byte = entropy->next_output_byte; + cinfo->dest->free_in_buffer = entropy->free_in_buffer; +} + + +/* + * Finish up a statistics-gathering pass and create the new Huffman tables. + */ + +METHODDEF(void) +finish_pass_gather_phuff (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyc->entropy_private; + boolean is_DC_band; + int ci, tbl; + jpeg_component_info * compptr; + JHUFF_TBL **htblptr; + boolean did[NUM_HUFF_TBLS]; + + /* Flush out buffered data (all we care about is counting the EOB symbol) */ + emit_eobrun(entropy); + + is_DC_band = (cinfo->Ss == 0); + + /* It's important not to apply jpeg_gen_optimal_table more than once + * per table, because it clobbers the input frequency counts! + */ + MEMZERO(did, SIZEOF(did)); + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + if (is_DC_band) { + if (cinfo->Ah != 0) /* DC refinement needs no table */ + continue; + tbl = compptr->dc_tbl_no; + } else { + tbl = compptr->ac_tbl_no; + } + if (! did[tbl]) { + if (is_DC_band) + htblptr = & cinfo->dc_huff_tbl_ptrs[tbl]; + else + htblptr = & cinfo->ac_huff_tbl_ptrs[tbl]; + if (*htblptr == NULL) + *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); + jpeg_gen_optimal_table(cinfo, *htblptr, entropy->count_ptrs[tbl]); + did[tbl] = TRUE; + } + } +} + + +METHODDEF(boolean) +need_optimization_pass (j_compress_ptr cinfo) +{ + return (cinfo->Ss != 0 || cinfo->Ah == 0); +} + + +/* + * Module initialization routine for progressive Huffman entropy encoding. + */ + +GLOBAL(void) +jinit_phuff_encoder (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + phuff_entropy_ptr entropy; + int i; + + entropy = (phuff_entropy_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(phuff_entropy_encoder)); + lossyc->entropy_private = (struct jpeg_entropy_encoder *) entropy; + lossyc->pub.entropy_start_pass = start_pass_phuff; + lossyc->pub.need_optimization_pass = need_optimization_pass; + + /* Mark tables unallocated */ + for (i = 0; i < NUM_HUFF_TBLS; i++) { + entropy->derived_tbls[i] = NULL; + entropy->count_ptrs[i] = NULL; + } + entropy->bit_buffer = NULL; /* needed only in AC refinement scan */ +} + +#endif /* C_PROGRESSIVE_SUPPORTED */ diff --git a/src/gdcmjpeg/jcpred.c b/src/gdcmjpeg/jcpred.c new file mode 100644 index 00000000..293596c1 --- /dev/null +++ b/src/gdcmjpeg/jcpred.c @@ -0,0 +1,301 @@ +/* + * jcpred.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains sample differencing for lossless JPEG. + * + * In order to avoid paying the performance penalty of having to check the + * predictor being used and the row being processed for each call of the + * undifferencer, and to promote optimization, we have separate differencing + * functions for each case. + * + * We are able to avoid duplicating source code by implementing the predictors + * and differencers as macros. Each of the differencing functions are + * simply wrappers around a DIFFERENCE macro with the appropriate PREDICTOR + * macro passed as an argument. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ + + +#ifdef C_LOSSLESS_SUPPORTED + +/* Private predictor object */ + +typedef struct { + /* MCU-rows left in the restart interval for each component */ + unsigned int restart_rows_to_go[MAX_COMPONENTS]; +} c_predictor; + +typedef c_predictor * c_pred_ptr; + +/* Forward declarations */ +LOCAL(void) reset_predictor + JPP((j_compress_ptr cinfo, int ci)); +METHODDEF(void) start_pass + JPP((j_compress_ptr cinfo)); + + +/* Predictor for the first column of the first row: 2^(P-Pt-1) */ +#define INITIAL_PREDICTORx (1 << (cinfo->data_precision - cinfo->Al - 1)) + +/* Predictor for the first column of the remaining rows: Rb */ +#define INITIAL_PREDICTOR2 GETJSAMPLE(prev_row[0]) + + +/* + * 1-Dimensional differencer routine. + * + * This macro implements the 1-D horizontal predictor (1). INITIAL_PREDICTOR + * is used as the special case predictor for the first column, which must be + * either INITIAL_PREDICTOR2 or INITIAL_PREDICTORx. The remaining samples + * use PREDICTOR1. + */ + +#define DIFFERENCE_1D(INITIAL_PREDICTOR) \ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; \ + c_pred_ptr pred = (c_pred_ptr) losslsc->pred_private; \ + boolean restart = FALSE; \ + unsigned int xindex; \ + int samp, Ra; \ + \ + samp = GETJSAMPLE(input_buf[0]); \ + diff_buf[0] = samp - INITIAL_PREDICTOR; \ + \ + for (xindex = 1; xindex < width; xindex++) { \ + Ra = samp; \ + samp = GETJSAMPLE(input_buf[xindex]); \ + diff_buf[xindex] = samp - PREDICTOR1; \ + } \ + \ + /* Account for restart interval (no-op if not using restarts) */ \ + if (cinfo->restart_interval) { \ + if (--(pred->restart_rows_to_go[ci]) == 0) { \ + reset_predictor(cinfo, ci); \ + restart = TRUE; \ + } \ + } + + +/* + * 2-Dimensional differencer routine. + * + * This macro implements the 2-D horizontal predictors (#2-7). PREDICTOR2 is + * used as the special case predictor for the first column. The remaining + * samples use PREDICTOR, which is a function of Ra, Rb, Rc. + * + * Because prev_row and output_buf may point to the same storage area (in an + * interleaved image with Vi=1, for example), we must take care to buffer Rb/Rc + * before writing the current reconstructed sample value into output_buf. + */ + +#define DIFFERENCE_2D(PREDICTOR) \ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; \ + c_pred_ptr pred = (c_pred_ptr) losslsc->pred_private; \ + unsigned int xindex; \ + int samp, Ra, Rb, Rc; \ + \ + Rb = GETJSAMPLE(prev_row[0]); \ + samp = GETJSAMPLE(input_buf[0]); \ + diff_buf[0] = samp - PREDICTOR2; \ + \ + for (xindex = 1; xindex < width; xindex++) { \ + Rc = Rb; \ + Rb = GETJSAMPLE(prev_row[xindex]); \ + Ra = samp; \ + samp = GETJSAMPLE(input_buf[xindex]); \ + diff_buf[xindex] = samp - PREDICTOR; \ + } \ + \ + /* Account for restart interval (no-op if not using restarts) */ \ + if (cinfo->restart_interval) { \ + if (--pred->restart_rows_to_go[ci] == 0) \ + reset_predictor(cinfo, ci); \ + } + + +/* + * Differencers for the all rows but the first in a scan or restart interval. + * The first sample in the row is differenced using the vertical + * predictor (2). The rest of the samples are differenced using the + * predictor specified in the scan header. + */ + +METHODDEF(void) +jpeg_difference1(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + DIFFERENCE_1D(INITIAL_PREDICTOR2); +} + +METHODDEF(void) +jpeg_difference2(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + DIFFERENCE_2D(PREDICTOR2); +} + +METHODDEF(void) +jpeg_difference3(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + DIFFERENCE_2D(PREDICTOR3); +} + +METHODDEF(void) +jpeg_difference4(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + DIFFERENCE_2D(PREDICTOR4); +} + +METHODDEF(void) +jpeg_difference5(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + SHIFT_TEMPS + DIFFERENCE_2D(PREDICTOR5); +} + +METHODDEF(void) +jpeg_difference6(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + SHIFT_TEMPS + DIFFERENCE_2D(PREDICTOR6); +} + +METHODDEF(void) +jpeg_difference7(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + SHIFT_TEMPS + DIFFERENCE_2D(PREDICTOR7); +} + + +/* + * Differencer for the first row in a scan or restart interval. The first + * sample in the row is differenced using the special predictor constant + * x=2^(P-Pt-1). The rest of the samples are differenced using the + * 1-D horizontal predictor (1). + */ + +METHODDEF(void) +jpeg_difference_first_row(j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width) +{ + DIFFERENCE_1D(INITIAL_PREDICTORx); + (void)prev_row; + + /* + * Now that we have differenced the first row, we want to use the + * differencer which corresponds to the predictor specified in the + * scan header. + * + * Note that we don't to do this if we have just reset the predictor + * for a new restart interval. + */ + if (!restart) { + switch (cinfo->Ss) { + case 1: + losslsc->predict_difference[ci] = jpeg_difference1; + break; + case 2: + losslsc->predict_difference[ci] = jpeg_difference2; + break; + case 3: + losslsc->predict_difference[ci] = jpeg_difference3; + break; + case 4: + losslsc->predict_difference[ci] = jpeg_difference4; + break; + case 5: + losslsc->predict_difference[ci] = jpeg_difference5; + break; + case 6: + losslsc->predict_difference[ci] = jpeg_difference6; + break; + case 7: + losslsc->predict_difference[ci] = jpeg_difference7; + break; + } + } +} + +/* + * Reset predictor at the start of a pass or restart interval. + */ + +LOCAL(void) +reset_predictor (j_compress_ptr cinfo, int ci) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_pred_ptr pred = (c_pred_ptr) losslsc->pred_private; + + /* Initialize restart counter */ + pred->restart_rows_to_go[ci] = + cinfo->restart_interval / cinfo->MCUs_per_row; + + /* Set difference function to first row function */ + losslsc->predict_difference[ci] = jpeg_difference_first_row; +} + + +/* + * Initialize for an input processing pass. + */ + +METHODDEF(void) +start_pass (j_compress_ptr cinfo) +{ + /* j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; */ + /* c_pred_ptr pred = (c_pred_ptr) losslsc->pred_private; */ + int ci; + + /* Check that the restart interval is an integer multiple of the number + * of MCU in an MCU-row. + */ + if (cinfo->restart_interval % cinfo->MCUs_per_row != 0) + ERREXIT2(cinfo, JERR_BAD_RESTART, + cinfo->restart_interval, cinfo->MCUs_per_row); + + /* Set predictors for start of pass */ + for (ci = 0; ci < cinfo->num_components; ci++) + reset_predictor(cinfo, ci); +} + + +/* + * Module initialization routine for the differencer. + */ + +GLOBAL(void) +jinit_differencer (j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + c_pred_ptr pred; + + pred = (c_pred_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(c_predictor)); + losslsc->pred_private = (void *) pred; + losslsc->predict_start_pass = start_pass; +} + +#endif /* C_LOSSLESS_SUPPORTED */ + diff --git a/src/gdcmjpeg/jcprepct.c b/src/gdcmjpeg/jcprepct.c new file mode 100644 index 00000000..18854819 --- /dev/null +++ b/src/gdcmjpeg/jcprepct.c @@ -0,0 +1,354 @@ +/* + * jcprepct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the compression preprocessing controller. + * This controller manages the color conversion, downsampling, + * and edge expansion steps. + * + * Most of the complexity here is associated with buffering input rows + * as required by the downsampler. See the comments at the head of + * jcsample.c for the downsampler's needs. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* At present, jcsample.c can request context rows only for smoothing. + * In the future, we might also need context rows for CCIR601 sampling + * or other more-complex downsampling procedures. The code to support + * context rows should be compiled only if needed. + */ +#ifdef INPUT_SMOOTHING_SUPPORTED +#define CONTEXT_ROWS_SUPPORTED +#endif + + +/* + * For the simple (no-context-row) case, we just need to buffer one + * row group's worth of pixels for the downsampling step. At the bottom of + * the image, we pad to a full row group by replicating the last pixel row. + * The downsampler's last output row is then replicated if needed to pad + * out to a full iMCU row. + * + * When providing context rows, we must buffer three row groups' worth of + * pixels. Three row groups are physically allocated, but the row pointer + * arrays are made five row groups high, with the extra pointers above and + * below "wrapping around" to point to the last and first real row groups. + * This allows the downsampler to access the proper context rows. + * At the top and bottom of the image, we create dummy context rows by + * copying the first or last real pixel row. This copying could be avoided + * by pointer hacking as is done in jdmainct.c, but it doesn't seem worth the + * trouble on the compression side. + */ + + +/* Private buffer controller object */ + +typedef struct { + struct jpeg_c_prep_controller pub; /* public fields */ + + /* Downsampling input buffer. This buffer holds color-converted data + * until we have enough to do a downsample step. + */ + JSAMPARRAY color_buf[MAX_COMPONENTS]; + + JDIMENSION rows_to_go; /* counts rows remaining in source image */ + int next_buf_row; /* index of next row to store in color_buf */ + +#ifdef CONTEXT_ROWS_SUPPORTED /* only needed for context case */ + int this_row_group; /* starting row index of group to process */ + int next_buf_stop; /* downsample when we reach this index */ +#endif +} my_prep_controller; + +typedef my_prep_controller * my_prep_ptr; + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_prep (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + my_prep_ptr prep = (my_prep_ptr) cinfo->prep; + + if (pass_mode != JBUF_PASS_THRU) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + + /* Initialize total-height counter for detecting bottom of image */ + prep->rows_to_go = cinfo->image_height; + /* Mark the conversion buffer empty */ + prep->next_buf_row = 0; +#ifdef CONTEXT_ROWS_SUPPORTED + /* Preset additional state variables for context mode. + * These aren't used in non-context mode, so we needn't test which mode. + */ + prep->this_row_group = 0; + /* Set next_buf_stop to stop after two row groups have been read in. */ + prep->next_buf_stop = 2 * cinfo->max_v_samp_factor; +#endif +} + + +/* + * Expand an image vertically from height input_rows to height output_rows, + * by duplicating the bottom row. + */ + +LOCAL(void) +expand_bottom_edge (JSAMPARRAY image_data, JDIMENSION num_cols, + int input_rows, int output_rows) +{ + register int row; + + for (row = input_rows; row < output_rows; row++) { + jcopy_sample_rows(image_data, input_rows-1, image_data, row, + 1, num_cols); + } +} + + +/* + * Process some data in the simple no-context case. + * + * Preprocessor output data is counted in "row groups". A row group + * is defined to be v_samp_factor sample rows of each component. + * Downsampling will produce this much data from each max_v_samp_factor + * input rows. + */ + +METHODDEF(void) +pre_process_data (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, + JDIMENSION in_rows_avail, + JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr, + JDIMENSION out_row_groups_avail) +{ + my_prep_ptr prep = (my_prep_ptr) cinfo->prep; + int numrows, ci; + JDIMENSION inrows; + jpeg_component_info * compptr; + + while (*in_row_ctr < in_rows_avail && + *out_row_group_ctr < out_row_groups_avail) { + /* Do color conversion to fill the conversion buffer. */ + inrows = in_rows_avail - *in_row_ctr; + numrows = cinfo->max_v_samp_factor - prep->next_buf_row; + numrows = (int) MIN((JDIMENSION) numrows, inrows); + (*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr, + prep->color_buf, + (JDIMENSION) prep->next_buf_row, + numrows); + *in_row_ctr += numrows; + prep->next_buf_row += numrows; + prep->rows_to_go -= numrows; + /* If at bottom of image, pad to fill the conversion buffer. */ + if (prep->rows_to_go == 0 && + prep->next_buf_row < cinfo->max_v_samp_factor) { + for (ci = 0; ci < cinfo->num_components; ci++) { + expand_bottom_edge(prep->color_buf[ci], cinfo->image_width, + prep->next_buf_row, cinfo->max_v_samp_factor); + } + prep->next_buf_row = cinfo->max_v_samp_factor; + } + /* If we've filled the conversion buffer, empty it. */ + if (prep->next_buf_row == cinfo->max_v_samp_factor) { + (*cinfo->downsample->downsample) (cinfo, + prep->color_buf, (JDIMENSION) 0, + output_buf, *out_row_group_ctr); + prep->next_buf_row = 0; + (*out_row_group_ctr)++; + } + /* If at bottom of image, pad the output to a full iMCU height. + * Note we assume the caller is providing a one-iMCU-height output buffer! + */ + if (prep->rows_to_go == 0 && + *out_row_group_ctr < out_row_groups_avail) { + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + expand_bottom_edge(output_buf[ci], + compptr->width_in_data_units * cinfo->data_unit, + (int) (*out_row_group_ctr * compptr->v_samp_factor), + (int) (out_row_groups_avail * compptr->v_samp_factor)); + } + *out_row_group_ctr = out_row_groups_avail; + break; /* can exit outer loop without test */ + } + } +} + + +#ifdef CONTEXT_ROWS_SUPPORTED + +/* + * Process some data in the context case. + */ + +METHODDEF(void) +pre_process_context (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, + JDIMENSION in_rows_avail, + JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr, + JDIMENSION out_row_groups_avail) +{ + my_prep_ptr prep = (my_prep_ptr) cinfo->prep; + int numrows, ci; + int buf_height = cinfo->max_v_samp_factor * 3; + JDIMENSION inrows; + + while (*out_row_group_ctr < out_row_groups_avail) { + if (*in_row_ctr < in_rows_avail) { + /* Do color conversion to fill the conversion buffer. */ + inrows = in_rows_avail - *in_row_ctr; + numrows = prep->next_buf_stop - prep->next_buf_row; + numrows = (int) MIN((JDIMENSION) numrows, inrows); + (*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr, + prep->color_buf, + (JDIMENSION) prep->next_buf_row, + numrows); + /* Pad at top of image, if first time through */ + if (prep->rows_to_go == cinfo->image_height) { + for (ci = 0; ci < cinfo->num_components; ci++) { + int row; + for (row = 1; row <= cinfo->max_v_samp_factor; row++) { + jcopy_sample_rows(prep->color_buf[ci], 0, + prep->color_buf[ci], -row, + 1, cinfo->image_width); + } + } + } + *in_row_ctr += numrows; + prep->next_buf_row += numrows; + prep->rows_to_go -= numrows; + } else { + /* Return for more data, unless we are at the bottom of the image. */ + if (prep->rows_to_go != 0) + break; + /* When at bottom of image, pad to fill the conversion buffer. */ + if (prep->next_buf_row < prep->next_buf_stop) { + for (ci = 0; ci < cinfo->num_components; ci++) { + expand_bottom_edge(prep->color_buf[ci], cinfo->image_width, + prep->next_buf_row, prep->next_buf_stop); + } + prep->next_buf_row = prep->next_buf_stop; + } + } + /* If we've gotten enough data, downsample a row group. */ + if (prep->next_buf_row == prep->next_buf_stop) { + (*cinfo->downsample->downsample) (cinfo, + prep->color_buf, + (JDIMENSION) prep->this_row_group, + output_buf, *out_row_group_ctr); + (*out_row_group_ctr)++; + /* Advance pointers with wraparound as necessary. */ + prep->this_row_group += cinfo->max_v_samp_factor; + if (prep->this_row_group >= buf_height) + prep->this_row_group = 0; + if (prep->next_buf_row >= buf_height) + prep->next_buf_row = 0; + prep->next_buf_stop = prep->next_buf_row + cinfo->max_v_samp_factor; + } + } +} + + +/* + * Create the wrapped-around downsampling input buffer needed for context mode. + */ + +LOCAL(void) +create_context_buffer (j_compress_ptr cinfo) +{ + my_prep_ptr prep = (my_prep_ptr) cinfo->prep; + int rgroup_height = cinfo->max_v_samp_factor; + int ci, i; + jpeg_component_info * compptr; + JSAMPARRAY true_buffer, fake_buffer; + + /* Grab enough space for fake row pointers for all the components; + * we need five row groups' worth of pointers for each component. + */ + fake_buffer = (JSAMPARRAY) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (cinfo->num_components * 5 * rgroup_height) * + SIZEOF(JSAMPROW)); + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Allocate the actual buffer space (3 row groups) for this component. + * We make the buffer wide enough to allow the downsampler to edge-expand + * horizontally within the buffer, if it so chooses. + */ + true_buffer = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) (((long) compptr->width_in_data_units * cinfo->data_unit * + cinfo->max_h_samp_factor) / compptr->h_samp_factor), + (JDIMENSION) (3 * rgroup_height)); + /* Copy true buffer row pointers into the middle of the fake row array */ + MEMCOPY(fake_buffer + rgroup_height, true_buffer, + 3 * rgroup_height * SIZEOF(JSAMPROW)); + /* Fill in the above and below wraparound pointers */ + for (i = 0; i < rgroup_height; i++) { + fake_buffer[i] = true_buffer[2 * rgroup_height + i]; + fake_buffer[4 * rgroup_height + i] = true_buffer[i]; + } + prep->color_buf[ci] = fake_buffer + rgroup_height; + fake_buffer += 5 * rgroup_height; /* point to space for next component */ + } +} + +#endif /* CONTEXT_ROWS_SUPPORTED */ + + +/* + * Initialize preprocessing controller. + */ + +GLOBAL(void) +jinit_c_prep_controller (j_compress_ptr cinfo, boolean need_full_buffer) +{ + my_prep_ptr prep; + int ci; + jpeg_component_info * compptr; + + if (need_full_buffer) /* safety check */ + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + + prep = (my_prep_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_prep_controller)); + cinfo->prep = (struct jpeg_c_prep_controller *) prep; + prep->pub.start_pass = start_pass_prep; + + /* Allocate the color conversion buffer. + * We make the buffer wide enough to allow the downsampler to edge-expand + * horizontally within the buffer, if it so chooses. + */ + if (cinfo->downsample->need_context_rows) { + /* Set up to provide context rows */ +#ifdef CONTEXT_ROWS_SUPPORTED + prep->pub.pre_process_data = pre_process_context; + create_context_buffer(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + /* No context, just make it tall enough for one row group */ + prep->pub.pre_process_data = pre_process_data; + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + prep->color_buf[ci] = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) (((long) compptr->width_in_data_units * cinfo->data_unit * + cinfo->max_h_samp_factor) / compptr->h_samp_factor), + (JDIMENSION) cinfo->max_v_samp_factor); + } + } +} diff --git a/src/gdcmjpeg/jcsample.c b/src/gdcmjpeg/jcsample.c new file mode 100644 index 00000000..5b5fb79e --- /dev/null +++ b/src/gdcmjpeg/jcsample.c @@ -0,0 +1,520 @@ +/* + * jcsample.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains downsampling routines. + * + * Downsampling input data is counted in "row groups". A row group + * is defined to be max_v_samp_factor pixel rows of each component, + * from which the downsampler produces v_samp_factor sample rows. + * A single row group is processed in each call to the downsampler module. + * + * The downsampler is responsible for edge-expansion of its output data + * to fill an integral number of DCT blocks horizontally. The source buffer + * may be modified if it is helpful for this purpose (the source buffer is + * allocated wide enough to correspond to the desired output width). + * The caller (the prep controller) is responsible for vertical padding. + * + * The downsampler may request "context rows" by setting need_context_rows + * during startup. In this case, the input arrays will contain at least + * one row group's worth of pixels above and below the passed-in data; + * the caller will create dummy rows at image top and bottom by replicating + * the first or last real pixel row. + * + * An excellent reference for image resampling is + * Digital Image Warping, George Wolberg, 1990. + * Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7. + * + * The downsampling algorithm used here is a simple average of the source + * pixels covered by the output pixel. The hi-falutin sampling literature + * refers to this as a "box filter". In general the characteristics of a box + * filter are not very good, but for the specific cases we normally use (1:1 + * and 2:1 ratios) the box is equivalent to a "triangle filter" which is not + * nearly so bad. If you intend to use other sampling ratios, you'd be well + * advised to improve this code. + * + * A simple input-smoothing capability is provided. This is mainly intended + * for cleaning up color-dithered GIF input files (if you find it inadequate, + * we suggest using an external filtering program such as pnmconvol). When + * enabled, each input pixel P is replaced by a weighted sum of itself and its + * eight neighbors. P's weight is 1-8*SF and each neighbor's weight is SF, + * where SF = (smoothing_factor / 1024). + * Currently, smoothing is only supported for 2h2v sampling factors. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Pointer to routine to downsample a single component */ +typedef JMETHOD(void, downsample1_ptr, + (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data)); + +/* Private subobject */ + +typedef struct { + struct jpeg_downsampler pub; /* public fields */ + + /* Downsampling method pointers, one per component */ + downsample1_ptr methods[MAX_COMPONENTS]; +} my_downsampler; + +typedef my_downsampler * my_downsample_ptr; + + +/* + * Initialize for a downsampling pass. + */ + +METHODDEF(void) +start_pass_downsample (j_compress_ptr cinfo) +{ + (void)cinfo; + /* no work for now */ +} + + +/* + * Expand a component horizontally from width input_cols to width output_cols, + * by duplicating the rightmost samples. + */ + +LOCAL(void) +expand_right_edge (JSAMPARRAY image_data, int num_rows, + JDIMENSION input_cols, JDIMENSION output_cols) +{ + register JSAMPROW ptr; + register JSAMPLE pixval; + register int count; + int row; + int numcols = (int) (output_cols - input_cols); + + if (numcols > 0) { + for (row = 0; row < num_rows; row++) { + ptr = image_data[row] + input_cols; + pixval = ptr[-1]; /* don't need GETJSAMPLE() here */ + for (count = numcols; count > 0; count--) + *ptr++ = pixval; + } + } +} + + +/* + * Do downsampling for a whole row group (all components). + * + * In this version we simply downsample each component independently. + */ + +METHODDEF(void) +sep_downsample (j_compress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION in_row_index, + JSAMPIMAGE output_buf, JDIMENSION out_row_group_index) +{ + my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample; + int ci; + jpeg_component_info * compptr; + JSAMPARRAY in_ptr, out_ptr; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + in_ptr = input_buf[ci] + in_row_index; + out_ptr = output_buf[ci] + (out_row_group_index * compptr->v_samp_factor); + (*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr); + } +} + + +/* + * Downsample pixel values of a single component. + * One row group is processed per call. + * This version handles arbitrary integral sampling ratios, without smoothing. + * Note that this version is not actually used for customary sampling ratios. + */ + +METHODDEF(void) +int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data) +{ + int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v; + JDIMENSION outcol, outcol_h; /* outcol_h == outcol*h_expand */ + JDIMENSION output_cols = compptr->width_in_data_units * cinfo->data_unit; + JSAMPROW inptr, outptr; + INT32 outvalue; + + h_expand = cinfo->max_h_samp_factor / compptr->h_samp_factor; + v_expand = cinfo->max_v_samp_factor / compptr->v_samp_factor; + numpix = h_expand * v_expand; + numpix2 = numpix/2; + + /* Expand input data enough to let all the output samples be generated + * by the standard loop. Special-casing padded output would be more + * efficient. + */ + expand_right_edge(input_data, cinfo->max_v_samp_factor, + cinfo->image_width, output_cols * h_expand); + + inrow = 0; + for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { + outptr = output_data[outrow]; + for (outcol = 0, outcol_h = 0; outcol < output_cols; + outcol++, outcol_h += h_expand) { + outvalue = 0; + for (v = 0; v < v_expand; v++) { + inptr = input_data[inrow+v] + outcol_h; + for (h = 0; h < h_expand; h++) { + outvalue += (INT32) GETJSAMPLE(*inptr++); + } + } + *outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix); + } + inrow += v_expand; + } +} + + +/* + * Downsample pixel values of a single component. + * This version handles the special case of a full-size component, + * without smoothing. + */ + +METHODDEF(void) +fullsize_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data) +{ + /* Copy the data */ + jcopy_sample_rows(input_data, 0, output_data, 0, + cinfo->max_v_samp_factor, cinfo->image_width); + /* Edge-expand */ + expand_right_edge(output_data, cinfo->max_v_samp_factor, + cinfo->image_width, compptr->width_in_data_units * cinfo->data_unit); +} + + +/* + * Downsample pixel values of a single component. + * This version handles the common case of 2:1 horizontal and 1:1 vertical, + * without smoothing. + * + * A note about the "bias" calculations: when rounding fractional values to + * integer, we do not want to always round 0.5 up to the next integer. + * If we did that, we'd introduce a noticeable bias towards larger values. + * Instead, this code is arranged so that 0.5 will be rounded up or down at + * alternate pixel locations (a simple ordered dither pattern). + */ + +METHODDEF(void) +h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data) +{ + int outrow; + JDIMENSION outcol; + JDIMENSION output_cols = compptr->width_in_data_units * cinfo->data_unit; + register JSAMPROW inptr, outptr; + register int bias; + + /* Expand input data enough to let all the output samples be generated + * by the standard loop. Special-casing padded output would be more + * efficient. + */ + expand_right_edge(input_data, cinfo->max_v_samp_factor, + cinfo->image_width, output_cols * 2); + + for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { + outptr = output_data[outrow]; + inptr = input_data[outrow]; + bias = 0; /* bias = 0,1,0,1,... for successive samples */ + for (outcol = 0; outcol < output_cols; outcol++) { + *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1]) + + bias) >> 1); + bias ^= 1; /* 0=>1, 1=>0 */ + inptr += 2; + } + } +} + + +/* + * Downsample pixel values of a single component. + * This version handles the standard case of 2:1 horizontal and 2:1 vertical, + * without smoothing. + */ + +METHODDEF(void) +h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data) +{ + int inrow, outrow; + JDIMENSION outcol; + JDIMENSION output_cols = compptr->width_in_data_units * cinfo->data_unit; + register JSAMPROW inptr0, inptr1, outptr; + register int bias; + + /* Expand input data enough to let all the output samples be generated + * by the standard loop. Special-casing padded output would be more + * efficient. + */ + expand_right_edge(input_data, cinfo->max_v_samp_factor, + cinfo->image_width, output_cols * 2); + + inrow = 0; + for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { + outptr = output_data[outrow]; + inptr0 = input_data[inrow]; + inptr1 = input_data[inrow+1]; + bias = 1; /* bias = 1,2,1,2,... for successive samples */ + for (outcol = 0; outcol < output_cols; outcol++) { + *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + + GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]) + + bias) >> 2); + bias ^= 3; /* 1=>2, 2=>1 */ + inptr0 += 2; inptr1 += 2; + } + inrow += 2; + } +} + + +#ifdef INPUT_SMOOTHING_SUPPORTED + +/* + * Downsample pixel values of a single component. + * This version handles the standard case of 2:1 horizontal and 2:1 vertical, + * with smoothing. One row of context is required. + */ + +METHODDEF(void) +h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data) +{ + int inrow, outrow; + JDIMENSION colctr; + JDIMENSION output_cols = compptr->width_in_data_units * cinfo->data_unit; + register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr; + INT32 membersum, neighsum, memberscale, neighscale; + + /* Expand input data enough to let all the output samples be generated + * by the standard loop. Special-casing padded output would be more + * efficient. + */ + expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2, + cinfo->image_width, output_cols * 2); + + /* We don't bother to form the individual "smoothed" input pixel values; + * we can directly compute the output which is the average of the four + * smoothed values. Each of the four member pixels contributes a fraction + * (1-8*SF) to its own smoothed image and a fraction SF to each of the three + * other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final + * output. The four corner-adjacent neighbor pixels contribute a fraction + * SF to just one smoothed pixel, or SF/4 to the final output; while the + * eight edge-adjacent neighbors contribute SF to each of two smoothed + * pixels, or SF/2 overall. In order to use integer arithmetic, these + * factors are scaled by 2^16 = 65536. + * Also recall that SF = smoothing_factor / 1024. + */ + + memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */ + neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */ + + inrow = 0; + for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { + outptr = output_data[outrow]; + inptr0 = input_data[inrow]; + inptr1 = input_data[inrow+1]; + above_ptr = input_data[inrow-1]; + below_ptr = input_data[inrow+2]; + + /* Special case for first column: pretend column -1 is same as column 0 */ + membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + + GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]); + neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) + + GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) + + GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[2]) + + GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[2]); + neighsum += neighsum; + neighsum += GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[2]) + + GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[2]); + membersum = membersum * memberscale + neighsum * neighscale; + *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); + inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2; + + for (colctr = output_cols - 2; colctr > 0; colctr--) { + /* sum of pixels directly mapped to this output element */ + membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + + GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]); + /* sum of edge-neighbor pixels */ + neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) + + GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) + + GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[2]) + + GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[2]); + /* The edge-neighbors count twice as much as corner-neighbors */ + neighsum += neighsum; + /* Add in the corner-neighbors */ + neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[2]) + + GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[2]); + /* form final output scaled up by 2^16 */ + membersum = membersum * memberscale + neighsum * neighscale; + /* round, descale and output it */ + *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); + inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2; + } + + /* Special case for last column */ + membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) + + GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]); + neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) + + GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) + + GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[1]) + + GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[1]); + neighsum += neighsum; + neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[1]) + + GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[1]); + membersum = membersum * memberscale + neighsum * neighscale; + *outptr = (JSAMPLE) ((membersum + 32768) >> 16); + + inrow += 2; + } +} + + +/* + * Downsample pixel values of a single component. + * This version handles the special case of a full-size component, + * with smoothing. One row of context is required. + */ + +METHODDEF(void) +fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr, + JSAMPARRAY input_data, JSAMPARRAY output_data) +{ + int outrow; + JDIMENSION colctr; + JDIMENSION output_cols = compptr->width_in_data_units * cinfo->data_unit; + register JSAMPROW inptr, above_ptr, below_ptr, outptr; + INT32 membersum, neighsum, memberscale, neighscale; + int colsum, lastcolsum, nextcolsum; + + /* Expand input data enough to let all the output samples be generated + * by the standard loop. Special-casing padded output would be more + * efficient. + */ + expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2, + cinfo->image_width, output_cols); + + /* Each of the eight neighbor pixels contributes a fraction SF to the + * smoothed pixel, while the main pixel contributes (1-8*SF). In order + * to use integer arithmetic, these factors are multiplied by 2^16 = 65536. + * Also recall that SF = smoothing_factor / 1024. + */ + + memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */ + neighscale = cinfo->smoothing_factor * 64; /* scaled SF */ + + for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) { + outptr = output_data[outrow]; + inptr = input_data[outrow]; + above_ptr = input_data[outrow-1]; + below_ptr = input_data[outrow+1]; + + /* Special case for first column */ + colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) + + GETJSAMPLE(*inptr); + membersum = GETJSAMPLE(*inptr++); + nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) + + GETJSAMPLE(*inptr); + neighsum = colsum + (colsum - membersum) + nextcolsum; + membersum = membersum * memberscale + neighsum * neighscale; + *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); + lastcolsum = colsum; colsum = nextcolsum; + + for (colctr = output_cols - 2; colctr > 0; colctr--) { + membersum = GETJSAMPLE(*inptr++); + above_ptr++; below_ptr++; + nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) + + GETJSAMPLE(*inptr); + neighsum = lastcolsum + (colsum - membersum) + nextcolsum; + membersum = membersum * memberscale + neighsum * neighscale; + *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16); + lastcolsum = colsum; colsum = nextcolsum; + } + + /* Special case for last column */ + membersum = GETJSAMPLE(*inptr); + neighsum = lastcolsum + (colsum - membersum) + colsum; + membersum = membersum * memberscale + neighsum * neighscale; + *outptr = (JSAMPLE) ((membersum + 32768) >> 16); + + } +} + +#endif /* INPUT_SMOOTHING_SUPPORTED */ + + +/* + * Module initialization routine for downsampling. + * Note that we must select a routine for each component. + */ + +GLOBAL(void) +jinit_downsampler (j_compress_ptr cinfo) +{ + my_downsample_ptr downsample; + int ci; + jpeg_component_info * compptr; + boolean smoothok = TRUE; + + downsample = (my_downsample_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_downsampler)); + cinfo->downsample = (struct jpeg_downsampler *) downsample; + downsample->pub.start_pass = start_pass_downsample; + downsample->pub.downsample = sep_downsample; + downsample->pub.need_context_rows = FALSE; + + if (cinfo->CCIR601_sampling) + ERREXIT(cinfo, JERR_CCIR601_NOTIMPL); + + /* Verify we can handle the sampling factors, and set up method pointers */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + if (compptr->h_samp_factor == cinfo->max_h_samp_factor && + compptr->v_samp_factor == cinfo->max_v_samp_factor) { +#ifdef INPUT_SMOOTHING_SUPPORTED + if (cinfo->smoothing_factor) { + downsample->methods[ci] = fullsize_smooth_downsample; + downsample->pub.need_context_rows = TRUE; + } else +#endif + downsample->methods[ci] = fullsize_downsample; + } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor && + compptr->v_samp_factor == cinfo->max_v_samp_factor) { + smoothok = FALSE; + downsample->methods[ci] = h2v1_downsample; + } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor && + compptr->v_samp_factor * 2 == cinfo->max_v_samp_factor) { +#ifdef INPUT_SMOOTHING_SUPPORTED + if (cinfo->smoothing_factor) { + downsample->methods[ci] = h2v2_smooth_downsample; + downsample->pub.need_context_rows = TRUE; + } else +#endif + downsample->methods[ci] = h2v2_downsample; + } else if ((cinfo->max_h_samp_factor % compptr->h_samp_factor) == 0 && + (cinfo->max_v_samp_factor % compptr->v_samp_factor) == 0) { + smoothok = FALSE; + downsample->methods[ci] = int_downsample; + } else + ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL); + } + +#ifdef INPUT_SMOOTHING_SUPPORTED + if (cinfo->smoothing_factor && !smoothok) + TRACEMS(cinfo, 0, JTRC_SMOOTH_NOTIMPL); +#endif +} diff --git a/src/gdcmjpeg/jcscale.c b/src/gdcmjpeg/jcscale.c new file mode 100644 index 00000000..f0539afe --- /dev/null +++ b/src/gdcmjpeg/jcscale.c @@ -0,0 +1,64 @@ +/* + * jcscale.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains sample downscaling by 2^Pt for lossless JPEG. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ + + +#ifdef C_LOSSLESS_SUPPORTED + +METHODDEF(void) +simple_downscale(j_compress_ptr cinfo, + JSAMPROW input_buf, JSAMPROW output_buf, JDIMENSION width) +{ + /* j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; */ + unsigned int xindex; + SHIFT_TEMPS + + for (xindex = 0; xindex < width; xindex++) + output_buf[xindex] = (JSAMPLE) RIGHT_SHIFT(GETJSAMPLE(input_buf[xindex]), + cinfo->Al); +} + + +METHODDEF(void) +noscale(j_compress_ptr cinfo, + JSAMPROW input_buf, JSAMPROW output_buf, JDIMENSION width) +{ + (void)cinfo; + MEMCOPY(output_buf, input_buf, width * SIZEOF(JSAMPLE)); + return; +} + + +METHODDEF(void) +scaler_start_pass (j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + + /* Set scaler function based on Pt */ + if (cinfo->Al) + losslsc->scaler_scale = simple_downscale; + else + losslsc->scaler_scale = noscale; +} + + +GLOBAL(void) +jinit_c_scaler (j_compress_ptr cinfo) +{ + j_lossless_c_ptr losslsc = (j_lossless_c_ptr) cinfo->codec; + + losslsc->scaler_start_pass = scaler_start_pass; +} + +#endif /* C_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jcshuff.c b/src/gdcmjpeg/jcshuff.c new file mode 100644 index 00000000..85557158 --- /dev/null +++ b/src/gdcmjpeg/jcshuff.c @@ -0,0 +1,662 @@ +/* + * jcshuff.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy encoding routines for sequential JPEG. + * + * Much of the complexity here has to do with supporting output suspension. + * If the data destination module demands suspension, we want to be able to + * back up to the start of the current MCU. To do this, we copy state + * variables into local working storage, and update them back to the + * permanent JPEG objects only upon successful completion of an MCU. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ +#include "jchuff.h" /* Declarations shared with jc*huff.c */ + + +/* Expanded entropy encoder object for Huffman encoding. + * + * The savable_state subrecord contains fields that change within an MCU, + * but must not be updated permanently until we complete the MCU. + */ + +typedef struct { + INT32 put_buffer; /* current bit-accumulation buffer */ + int put_bits; /* # of bits now in it */ + int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */ +} savable_state; + +/* This macro is to work around compilers with missing or broken + * structure assignment. You'll need to fix this code if you have + * such a compiler and you change MAX_COMPS_IN_SCAN. + */ + +#ifndef NO_STRUCT_ASSIGN +#define ASSIGN_STATE(dest,src) ((dest) = (src)) +#else +#if MAX_COMPS_IN_SCAN == 4 +#define ASSIGN_STATE(dest,src) \ + ((dest).put_buffer = (src).put_buffer, \ + (dest).put_bits = (src).put_bits, \ + (dest).last_dc_val[0] = (src).last_dc_val[0], \ + (dest).last_dc_val[1] = (src).last_dc_val[1], \ + (dest).last_dc_val[2] = (src).last_dc_val[2], \ + (dest).last_dc_val[3] = (src).last_dc_val[3]) +#endif +#endif + + +typedef struct { + savable_state saved; /* Bit buffer & DC state at start of MCU */ + + /* These fields are NOT loaded into local working state. */ + unsigned int restarts_to_go; /* MCUs left in this restart interval */ + int next_restart_num; /* next restart number to write (0-7) */ + + /* Pointers to derived tables (these workspaces have image lifespan) */ + c_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS]; + c_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS]; + +#ifdef ENTROPY_OPT_SUPPORTED /* Statistics tables for optimization */ + long * dc_count_ptrs[NUM_HUFF_TBLS]; + long * ac_count_ptrs[NUM_HUFF_TBLS]; +#endif +} shuff_entropy_encoder; + +typedef shuff_entropy_encoder * shuff_entropy_ptr; + +/* Working state while writing an MCU. + * This struct contains all the fields that are needed by subroutines. + */ + +typedef struct { + JOCTET * next_output_byte; /* => next byte to write in buffer */ + size_t free_in_buffer; /* # of byte spaces remaining in buffer */ + savable_state cur; /* Current bit buffer & DC state */ + j_compress_ptr cinfo; /* dump_buffer needs access to this */ +} working_state; + + +/* Forward declarations */ +METHODDEF(boolean) encode_mcu_huff JPP((j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(void) finish_pass_huff JPP((j_compress_ptr cinfo)); +#ifdef ENTROPY_OPT_SUPPORTED +METHODDEF(boolean) encode_mcu_gather JPP((j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(void) finish_pass_gather JPP((j_compress_ptr cinfo)); +#endif + + +/* + * Initialize for a Huffman-compressed scan. + * If gather_statistics is TRUE, we do not output anything during the scan, + * just count the Huffman symbols used and generate Huffman code tables. + */ + +METHODDEF(void) +start_pass_huff (j_compress_ptr cinfo, boolean gather_statistics) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyc->entropy_private; + int ci, dctbl, actbl; + jpeg_component_info * compptr; + + if (gather_statistics) { +#ifdef ENTROPY_OPT_SUPPORTED + lossyc->entropy_encode_mcu = encode_mcu_gather; + lossyc->pub.entropy_finish_pass = finish_pass_gather; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + lossyc->entropy_encode_mcu = encode_mcu_huff; + lossyc->pub.entropy_finish_pass = finish_pass_huff; + } + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + dctbl = compptr->dc_tbl_no; + actbl = compptr->ac_tbl_no; + if (gather_statistics) { +#ifdef ENTROPY_OPT_SUPPORTED + /* Check for invalid table indexes */ + /* (make_c_derived_tbl does this in the other path) */ + if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl); + if (actbl < 0 || actbl >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, actbl); + /* Allocate and zero the statistics tables */ + /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */ + if (entropy->dc_count_ptrs[dctbl] == NULL) + entropy->dc_count_ptrs[dctbl] = (long *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + 257 * SIZEOF(long)); + MEMZERO(entropy->dc_count_ptrs[dctbl], 257 * SIZEOF(long)); + if (entropy->ac_count_ptrs[actbl] == NULL) + entropy->ac_count_ptrs[actbl] = (long *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + 257 * SIZEOF(long)); + MEMZERO(entropy->ac_count_ptrs[actbl], 257 * SIZEOF(long)); +#endif + } else { + /* Compute derived values for Huffman tables */ + /* We may do this more than once for a table, but it's not expensive */ + jpeg_make_c_derived_tbl(cinfo, TRUE, dctbl, + & entropy->dc_derived_tbls[dctbl]); + jpeg_make_c_derived_tbl(cinfo, FALSE, actbl, + & entropy->ac_derived_tbls[actbl]); + } + /* Initialize DC predictions to 0 */ + entropy->saved.last_dc_val[ci] = 0; + } + + /* Initialize bit buffer to empty */ + entropy->saved.put_buffer = 0; + entropy->saved.put_bits = 0; + + /* Initialize restart stuff */ + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num = 0; +} + + +/* Outputting bytes to the file */ + +/* Emit a byte, taking 'action' if must suspend. */ +#define emit_byte(state,val,action) \ + { *(state)->next_output_byte++ = (JOCTET) (val); \ + if (--(state)->free_in_buffer == 0) \ + if (! dump_buffer(state)) \ + { action; } } + + +LOCAL(boolean) +dump_buffer (working_state * state) +/* Empty the output buffer; return TRUE if successful, FALSE if must suspend */ +{ + struct jpeg_destination_mgr * dest = state->cinfo->dest; + + if (! (*dest->empty_output_buffer) (state->cinfo)) + return FALSE; + /* After a successful buffer dump, must reset buffer pointers */ + state->next_output_byte = dest->next_output_byte; + state->free_in_buffer = dest->free_in_buffer; + return TRUE; +} + + +/* Outputting bits to the file */ + +/* Only the right 24 bits of put_buffer are used; the valid bits are + * left-justified in this part. At most 16 bits can be passed to emit_bits + * in one call, and we never retain more than 7 bits in put_buffer + * between calls, so 24 bits are sufficient. + */ + +INLINE +LOCAL(boolean) +emit_bits (working_state * state, unsigned int code, int size) +/* Emit some bits; return TRUE if successful, FALSE if must suspend */ +{ + /* This routine is heavily used, so it's worth coding tightly. */ + register INT32 put_buffer = (INT32) code; + register int put_bits = state->cur.put_bits; + + /* if size is 0, caller used an invalid Huffman table entry */ + if (size == 0) + ERREXIT(state->cinfo, JERR_HUFF_MISSING_CODE); + + put_buffer &= (((INT32) 1)<cur.put_buffer; /* and merge with old buffer contents */ + + while (put_bits >= 8) { + int c = (int) ((put_buffer >> 16) & 0xFF); + + emit_byte(state, c, return FALSE); + if (c == 0xFF) { /* need to stuff a zero byte? */ + emit_byte(state, 0, return FALSE); + } + put_buffer <<= 8; + put_bits -= 8; + } + + state->cur.put_buffer = put_buffer; /* update state variables */ + state->cur.put_bits = put_bits; + + return TRUE; +} + + +LOCAL(boolean) +flush_bits (working_state * state) +{ + if (! emit_bits(state, 0x7F, 7)) /* fill any partial byte with ones */ + return FALSE; + state->cur.put_buffer = 0; /* and reset bit-buffer to empty */ + state->cur.put_bits = 0; + return TRUE; +} + + +/* Encode a single block's worth of coefficients */ + +LOCAL(boolean) +encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val, + c_derived_tbl *dctbl, c_derived_tbl *actbl) +{ + register int temp, temp2; + register int nbits; + register int k, r, i; + + /* Encode the DC coefficient difference per section F.1.2.1 */ + + temp = temp2 = block[0] - last_dc_val; + + if (temp < 0) { + temp = -temp; /* temp is abs value of input */ + /* For a negative input, want temp2 = bitwise complement of abs(input) */ + /* This code assumes we are on a two's complement machine */ + temp2--; + } + + /* Find the number of bits needed for the magnitude of the coefficient */ + nbits = 0; + while (temp) { + nbits++; + temp >>= 1; + } + /* Check for out-of-range coefficient values. + * Since we're encoding a difference, the range limit is twice as much. + */ + if (nbits > MAX_COEF_BITS+1) + ERREXIT(state->cinfo, JERR_BAD_DCT_COEF); + + /* Emit the Huffman-coded symbol for the number of bits */ + if (! emit_bits(state, dctbl->ehufco[nbits], dctbl->ehufsi[nbits])) + return FALSE; + + /* Emit that number of bits of the value, if positive, */ + /* or the complement of its magnitude, if negative. */ + if (nbits) /* emit_bits rejects calls with size 0 */ + if (! emit_bits(state, (unsigned int) temp2, nbits)) + return FALSE; + + /* Encode the AC coefficients per section F.1.2.2 */ + + r = 0; /* r = run length of zeros */ + + for (k = 1; k < DCTSIZE2; k++) { + if ((temp = block[jpeg_natural_order[k]]) == 0) { + r++; + } else { + /* if run length > 15, must emit special run-length-16 codes (0xF0) */ + while (r > 15) { + if (! emit_bits(state, actbl->ehufco[0xF0], actbl->ehufsi[0xF0])) + return FALSE; + r -= 16; + } + + temp2 = temp; + if (temp < 0) { + temp = -temp; /* temp is abs value of input */ + /* This code assumes we are on a two's complement machine */ + temp2--; + } + + /* Find the number of bits needed for the magnitude of the coefficient */ + nbits = 1; /* there must be at least one 1 bit */ + while ((temp >>= 1)) + nbits++; + /* Check for out-of-range coefficient values */ + if (nbits > MAX_COEF_BITS) + ERREXIT(state->cinfo, JERR_BAD_DCT_COEF); + + /* Emit Huffman symbol for run length / number of bits */ + i = (r << 4) + nbits; + if (! emit_bits(state, actbl->ehufco[i], actbl->ehufsi[i])) + return FALSE; + + /* Emit that number of bits of the value, if positive, */ + /* or the complement of its magnitude, if negative. */ + if (! emit_bits(state, (unsigned int) temp2, nbits)) + return FALSE; + + r = 0; + } + } + + /* If the last coef(s) were zero, emit an end-of-block code */ + if (r > 0) + if (! emit_bits(state, actbl->ehufco[0], actbl->ehufsi[0])) + return FALSE; + + return TRUE; +} + + +/* + * Emit a restart marker & resynchronize predictions. + */ + +LOCAL(boolean) +emit_restart (working_state * state, int restart_num) +{ + int ci; + + if (! flush_bits(state)) + return FALSE; + + emit_byte(state, 0xFF, return FALSE); + emit_byte(state, JPEG_RST0 + restart_num, return FALSE); + + /* Re-initialize DC predictions to 0 */ + for (ci = 0; ci < state->cinfo->comps_in_scan; ci++) + state->cur.last_dc_val[ci] = 0; + + /* The restart counter is not updated until we successfully write the MCU. */ + + return TRUE; +} + + +/* + * Encode and output one MCU's worth of Huffman-compressed coefficients. + */ + +METHODDEF(boolean) +encode_mcu_huff (j_compress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyc->entropy_private; + working_state state; + int blkn, ci; + jpeg_component_info * compptr; + + /* Load up working state */ + state.next_output_byte = cinfo->dest->next_output_byte; + state.free_in_buffer = cinfo->dest->free_in_buffer; + ASSIGN_STATE(state.cur, entropy->saved); + state.cinfo = cinfo; + + /* Emit restart marker if needed */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! emit_restart(&state, entropy->next_restart_num)) + return FALSE; + } + + /* Encode the MCU data blocks */ + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + ci = cinfo->MCU_membership[blkn]; + compptr = cinfo->cur_comp_info[ci]; + if (! encode_one_block(&state, + MCU_data[blkn][0], state.cur.last_dc_val[ci], + entropy->dc_derived_tbls[compptr->dc_tbl_no], + entropy->ac_derived_tbls[compptr->ac_tbl_no])) + return FALSE; + /* Update last_dc_val */ + state.cur.last_dc_val[ci] = MCU_data[blkn][0][0]; + } + + /* Completed MCU, so update state */ + cinfo->dest->next_output_byte = state.next_output_byte; + cinfo->dest->free_in_buffer = state.free_in_buffer; + ASSIGN_STATE(entropy->saved, state.cur); + + /* Update restart-interval state too */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + entropy->restarts_to_go = cinfo->restart_interval; + entropy->next_restart_num++; + entropy->next_restart_num &= 7; + } + entropy->restarts_to_go--; + } + + return TRUE; +} + + +/* + * Finish up at the end of a Huffman-compressed scan. + */ + +METHODDEF(void) +finish_pass_huff (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyc->entropy_private; + working_state state; + + /* Load up working state ... flush_bits needs it */ + state.next_output_byte = cinfo->dest->next_output_byte; + state.free_in_buffer = cinfo->dest->free_in_buffer; + ASSIGN_STATE(state.cur, entropy->saved); + state.cinfo = cinfo; + + /* Flush out the last data */ + if (! flush_bits(&state)) + ERREXIT(cinfo, JERR_CANT_SUSPEND); + + /* Update state */ + cinfo->dest->next_output_byte = state.next_output_byte; + cinfo->dest->free_in_buffer = state.free_in_buffer; + ASSIGN_STATE(entropy->saved, state.cur); +} + + +/* + * Huffman coding optimization. + * + * We first scan the supplied data and count the number of uses of each symbol + * that is to be Huffman-coded. (This process MUST agree with the code above.) + * Then we build a Huffman coding tree for the observed counts. + * Symbols which are not needed at all for the particular image are not + * assigned any code, which saves space in the DHT marker as well as in + * the compressed data. + */ + +#ifdef ENTROPY_OPT_SUPPORTED + + +/* Process a single block's worth of coefficients */ + +LOCAL(void) +htest_one_block (j_compress_ptr cinfo, JCOEFPTR block, int last_dc_val, + long dc_counts[], long ac_counts[]) +{ + register int temp; + register int nbits; + register int k, r; + + /* Encode the DC coefficient difference per section F.1.2.1 */ + + temp = block[0] - last_dc_val; + if (temp < 0) + temp = -temp; + + /* Find the number of bits needed for the magnitude of the coefficient */ + nbits = 0; + while (temp) { + nbits++; + temp >>= 1; + } + /* Check for out-of-range coefficient values. + * Since we're encoding a difference, the range limit is twice as much. + */ + if (nbits > MAX_COEF_BITS+1) + ERREXIT(cinfo, JERR_BAD_DCT_COEF); + + /* Count the Huffman symbol for the number of bits */ + dc_counts[nbits]++; + + /* Encode the AC coefficients per section F.1.2.2 */ + + r = 0; /* r = run length of zeros */ + + for (k = 1; k < DCTSIZE2; k++) { + if ((temp = block[jpeg_natural_order[k]]) == 0) { + r++; + } else { + /* if run length > 15, must emit special run-length-16 codes (0xF0) */ + while (r > 15) { + ac_counts[0xF0]++; + r -= 16; + } + + /* Find the number of bits needed for the magnitude of the coefficient */ + if (temp < 0) + temp = -temp; + + /* Find the number of bits needed for the magnitude of the coefficient */ + nbits = 1; /* there must be at least one 1 bit */ + while ((temp >>= 1)) + nbits++; + /* Check for out-of-range coefficient values */ + if (nbits > MAX_COEF_BITS) + ERREXIT(cinfo, JERR_BAD_DCT_COEF); + + /* Count Huffman symbol for run length / number of bits */ + ac_counts[(r << 4) + nbits]++; + + r = 0; + } + } + + /* If the last coef(s) were zero, emit an end-of-block code */ + if (r > 0) + ac_counts[0]++; +} + + +/* + * Trial-encode one MCU's worth of Huffman-compressed coefficients. + * No data is actually output, so no suspension return is possible. + */ + +METHODDEF(boolean) +encode_mcu_gather (j_compress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyc->entropy_private; + int blkn, ci; + jpeg_component_info * compptr; + + /* Take care of restart intervals if needed */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) { + /* Re-initialize DC predictions to 0 */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) + entropy->saved.last_dc_val[ci] = 0; + /* Update restart state */ + entropy->restarts_to_go = cinfo->restart_interval; + } + entropy->restarts_to_go--; + } + + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + ci = cinfo->MCU_membership[blkn]; + compptr = cinfo->cur_comp_info[ci]; + htest_one_block(cinfo, MCU_data[blkn][0], entropy->saved.last_dc_val[ci], + entropy->dc_count_ptrs[compptr->dc_tbl_no], + entropy->ac_count_ptrs[compptr->ac_tbl_no]); + entropy->saved.last_dc_val[ci] = MCU_data[blkn][0][0]; + } + + return TRUE; +} + + +/* + * Finish up a statistics-gathering pass and create the new Huffman tables. + */ + +METHODDEF(void) +finish_pass_gather (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyc->entropy_private; + int ci, dctbl, actbl; + jpeg_component_info * compptr; + JHUFF_TBL **htblptr; + boolean did_dc[NUM_HUFF_TBLS]; + boolean did_ac[NUM_HUFF_TBLS]; + + /* It's important not to apply jpeg_gen_optimal_table more than once + * per table, because it clobbers the input frequency counts! + */ + MEMZERO(did_dc, SIZEOF(did_dc)); + MEMZERO(did_ac, SIZEOF(did_ac)); + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + dctbl = compptr->dc_tbl_no; + actbl = compptr->ac_tbl_no; + if (! did_dc[dctbl]) { + htblptr = & cinfo->dc_huff_tbl_ptrs[dctbl]; + if (*htblptr == NULL) + *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); + jpeg_gen_optimal_table(cinfo, *htblptr, entropy->dc_count_ptrs[dctbl]); + did_dc[dctbl] = TRUE; + } + if (! did_ac[actbl]) { + htblptr = & cinfo->ac_huff_tbl_ptrs[actbl]; + if (*htblptr == NULL) + *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); + jpeg_gen_optimal_table(cinfo, *htblptr, entropy->ac_count_ptrs[actbl]); + did_ac[actbl] = TRUE; + } + } +} + + +#endif /* ENTROPY_OPT_SUPPORTED */ + + +METHODDEF(boolean) +need_optimization_pass (j_compress_ptr cinfo) +{ + (void)cinfo; + return TRUE; +} + + +/* + * Module initialization routine for Huffman entropy encoding. + */ + +GLOBAL(void) +jinit_shuff_encoder (j_compress_ptr cinfo) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + shuff_entropy_ptr entropy; + int i; + + entropy = (shuff_entropy_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(shuff_entropy_encoder)); + lossyc->entropy_private = (struct jpeg_entropy_encoder *) entropy; + lossyc->pub.entropy_start_pass = start_pass_huff; + lossyc->pub.need_optimization_pass = need_optimization_pass; + + /* Mark tables unallocated */ + for (i = 0; i < NUM_HUFF_TBLS; i++) { + entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL; +#ifdef ENTROPY_OPT_SUPPORTED + entropy->dc_count_ptrs[i] = entropy->ac_count_ptrs[i] = NULL; +#endif + } +} diff --git a/src/gdcmjpeg/jctrans.c b/src/gdcmjpeg/jctrans.c new file mode 100644 index 00000000..0c94656a --- /dev/null +++ b/src/gdcmjpeg/jctrans.c @@ -0,0 +1,421 @@ +/* + * jctrans.c + * + * Copyright (C) 1995-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains library routines for transcoding compression, + * that is, writing raw DCT coefficient arrays to an output JPEG file. + * The routines in jcapimin.c will also be needed by a transcoder. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ + + +/* Forward declarations */ +LOCAL(void) transencode_master_selection + JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)); +LOCAL(void) transencode_codec + JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)); +LOCAL(void) transencode_coef_controller + JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)); + + +/* + * Compression initialization for writing raw-coefficient data. + * Before calling this, all parameters and a data destination must be set up. + * Call jpeg_finish_compress() to actually write the data. + * + * The number of passed virtual arrays must match cinfo->num_components. + * Note that the virtual arrays need not be filled or even realized at + * the time write_coefficients is called; indeed, if the virtual arrays + * were requested from this compression object's memory manager, they + * typically will be realized during this routine and filled afterwards. + */ + +GLOBAL(void) +jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays) +{ + if (cinfo->global_state != CSTATE_START) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + /* Mark all tables to be written */ + jpeg_suppress_tables(cinfo, FALSE); + /* (Re)initialize error mgr and destination modules */ + (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); + (*cinfo->dest->init_destination) (cinfo); + /* Perform master selection of active modules */ + transencode_master_selection(cinfo, coef_arrays); + /* Wait for jpeg_finish_compress() call */ + cinfo->next_scanline = 0; /* so jpeg_write_marker works */ + cinfo->global_state = CSTATE_WRCOEFS; +} + + +/* + * Initialize the compression object with default parameters, + * then copy from the source object all parameters needed for lossless + * transcoding. Parameters that can be varied without loss (such as + * scan script and Huffman optimization) are left in their default states. + */ + +GLOBAL(void) +jpeg_copy_critical_parameters (j_decompress_ptr srcinfo, + j_compress_ptr dstinfo) +{ + JQUANT_TBL ** qtblptr; + jpeg_component_info *incomp, *outcomp; + JQUANT_TBL *c_quant, *slot_quant; + int tblno, ci, coefi; + + /* Safety check to ensure start_compress not called yet. */ + if (dstinfo->global_state != CSTATE_START) + ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state); + /* Copy fundamental image dimensions */ + dstinfo->image_width = srcinfo->image_width; + dstinfo->image_height = srcinfo->image_height; + dstinfo->input_components = srcinfo->num_components; + dstinfo->in_color_space = srcinfo->jpeg_color_space; + /* Initialize all parameters to default values */ + jpeg_set_defaults(dstinfo); + /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB. + * Fix it to get the right header markers for the image colorspace. + */ + jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space); + dstinfo->data_precision = srcinfo->data_precision; + dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling; + /* Copy the source's quantization tables. */ + for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) { + if (srcinfo->quant_tbl_ptrs[tblno] != NULL) { + qtblptr = & dstinfo->quant_tbl_ptrs[tblno]; + if (*qtblptr == NULL) + *qtblptr = jpeg_alloc_quant_table((j_common_ptr) dstinfo); + MEMCOPY((*qtblptr)->quantval, + srcinfo->quant_tbl_ptrs[tblno]->quantval, + SIZEOF((*qtblptr)->quantval)); + (*qtblptr)->sent_table = FALSE; + } + } + /* Copy the source's per-component info. + * Note we assume jpeg_set_defaults has allocated the dest comp_info array. + */ + dstinfo->num_components = srcinfo->num_components; + if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS) + ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components, + MAX_COMPONENTS); + for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info; + ci < dstinfo->num_components; ci++, incomp++, outcomp++) { + outcomp->component_id = incomp->component_id; + outcomp->h_samp_factor = incomp->h_samp_factor; + outcomp->v_samp_factor = incomp->v_samp_factor; + outcomp->quant_tbl_no = incomp->quant_tbl_no; + /* Make sure saved quantization table for component matches the qtable + * slot. If not, the input file re-used this qtable slot. + * IJG encoder currently cannot duplicate this. + */ + tblno = outcomp->quant_tbl_no; + if (tblno < 0 || tblno >= NUM_QUANT_TBLS || + srcinfo->quant_tbl_ptrs[tblno] == NULL) + ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno); + slot_quant = srcinfo->quant_tbl_ptrs[tblno]; + c_quant = incomp->quant_table; + if (c_quant != NULL) { + for (coefi = 0; coefi < DCTSIZE2; coefi++) { + if (c_quant->quantval[coefi] != slot_quant->quantval[coefi]) + ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno); + } + } + /* Note: we do not copy the source's Huffman table assignments; + * instead we rely on jpeg_set_colorspace to have made a suitable choice. + */ + } + /* Also copy JFIF version and resolution information, if available. + * Strictly speaking this isn't "critical" info, but it's nearly + * always appropriate to copy it if available. In particular, + * if the application chooses to copy JFIF 1.02 extension markers from + * the source file, we need to copy the version to make sure we don't + * emit a file that has 1.02 extensions but a claimed version of 1.01. + * We will *not*, however, copy version info from mislabeled "2.01" files. + */ + if (srcinfo->saw_JFIF_marker) { + if (srcinfo->JFIF_major_version == 1) { + dstinfo->JFIF_major_version = srcinfo->JFIF_major_version; + dstinfo->JFIF_minor_version = srcinfo->JFIF_minor_version; + } + dstinfo->density_unit = srcinfo->density_unit; + dstinfo->X_density = srcinfo->X_density; + dstinfo->Y_density = srcinfo->Y_density; + } +} + + +/* + * Master selection of compression modules for transcoding. + * This substitutes for jcinit.c's initialization of the full compressor. + */ + +LOCAL(void) +transencode_master_selection (j_compress_ptr cinfo, + jvirt_barray_ptr * coef_arrays) +{ + cinfo->data_unit = DCTSIZE; + /* Although we don't actually use input_components for transcoding, + * jcmaster.c's initial_setup will complain if input_components is 0. + */ + cinfo->input_components = 1; + /* Initialize master control (includes parameter checking/processing) */ + jinit_c_master_control(cinfo, TRUE /* transcode only */); + + /* We need a special compression codec. */ + transencode_codec(cinfo, coef_arrays); + + jinit_marker_writer(cinfo); + + /* We can now tell the memory manager to allocate virtual arrays. */ + (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo); + + /* Write the datastream header (SOI, JFIF) immediately. + * Frame and scan headers are postponed till later. + * This lets application insert special markers after the SOI. + */ + (*cinfo->marker->write_file_header) (cinfo); +} + + +/* + * The rest of this file is a special implementation of the coefficient + * buffer controller. This is similar to jccoefct.c, but it handles only + * output from presupplied virtual arrays. Furthermore, we generate any + * dummy padding blocks on-the-fly rather than expecting them to be present + * in the arrays. + */ + +/* Private buffer controller object */ + +typedef struct { + JDIMENSION iMCU_row_num; /* iMCU row # within image */ + JDIMENSION mcu_ctr; /* counts MCUs processed in current row */ + int MCU_vert_offset; /* counts MCU rows within iMCU row */ + int MCU_rows_per_iMCU_row; /* number of such rows needed */ + + /* Virtual block array for each component. */ + jvirt_barray_ptr * whole_image; + + /* Workspace for constructing dummy blocks at right/bottom edges. */ + JBLOCKROW dummy_buffer[C_MAX_DATA_UNITS_IN_MCU]; +} c_coef_controller; + +typedef c_coef_controller * c_coef_ptr; + + +LOCAL(void) +start_iMCU_row (j_compress_ptr cinfo) +/* Reset within-iMCU-row counters for a new row */ +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + + /* In an interleaved scan, an MCU row is the same as an iMCU row. + * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows. + * But at the bottom of the image, process only what's left. + */ + if (cinfo->comps_in_scan > 1) { + coef->MCU_rows_per_iMCU_row = 1; + } else { + if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1)) + coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor; + else + coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height; + } + + coef->mcu_ctr = 0; + coef->MCU_vert_offset = 0; +} + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + + if (pass_mode != JBUF_CRANK_DEST) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + + coef->iMCU_row_num = 0; + start_iMCU_row(cinfo); +} + + +/* + * Process some data. + * We process the equivalent of one fully interleaved MCU row ("iMCU" row) + * per call, ie, v_samp_factor block rows for each component in the scan. + * The data is obtained from the virtual arrays and fed to the entropy coder. + * Returns TRUE if the iMCU row is completed, FALSE if suspended. + * + * NB: input_buf is ignored; it is likely to be a NULL pointer. + */ + +METHODDEF(boolean) +compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef = (c_coef_ptr) lossyc->coef_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + int blkn, ci, xindex, yindex, yoffset, blockcnt; + JDIMENSION start_col; + JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN]; + JBLOCKROW MCU_buffer[C_MAX_DATA_UNITS_IN_MCU]; + JBLOCKROW buffer_ptr; + jpeg_component_info *compptr; + (void)input_buf; + + /* Align the virtual buffers for the components used in this scan. */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + buffer[ci] = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index], + coef->iMCU_row_num * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, FALSE); + } + + /* Loop to process one whole iMCU row */ + for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; + yoffset++) { + for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row; + MCU_col_num++) { + /* Construct list of pointers to DCT blocks belonging to this MCU */ + blkn = 0; /* index of current DCT block within MCU */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + start_col = MCU_col_num * compptr->MCU_width; + blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width + : compptr->last_col_width; + for (yindex = 0; yindex < compptr->MCU_height; yindex++) { + if (coef->iMCU_row_num < last_iMCU_row || + yindex+yoffset < compptr->last_row_height) { + /* Fill in pointers to real blocks in this row */ + buffer_ptr = buffer[ci][yindex+yoffset] + start_col; + for (xindex = 0; xindex < blockcnt; xindex++) + MCU_buffer[blkn++] = buffer_ptr++; + } else { + /* At bottom of image, need a whole row of dummy blocks */ + xindex = 0; + } + /* Fill in any dummy blocks needed in this row. + * Dummy blocks are filled in the same way as in jccoefct.c: + * all zeroes in the AC entries, DC entries equal to previous + * block's DC value. The init routine has already zeroed the + * AC entries, so we need only set the DC entries correctly. + */ + for (; xindex < compptr->MCU_width; xindex++) { + MCU_buffer[blkn] = coef->dummy_buffer[blkn]; + MCU_buffer[blkn][0][0] = MCU_buffer[blkn-1][0][0]; + blkn++; + } + } + } + /* Try to write the MCU. */ + if (! (*lossyc->entropy_encode_mcu) (cinfo, MCU_buffer)) { + /* Suspension forced; update state counters and exit */ + coef->MCU_vert_offset = yoffset; + coef->mcu_ctr = MCU_col_num; + return FALSE; + } + } + /* Completed an MCU row, but perhaps not an iMCU row */ + coef->mcu_ctr = 0; + } + /* Completed the iMCU row, advance counters for next one */ + coef->iMCU_row_num++; + start_iMCU_row(cinfo); + return TRUE; +} + + +/* + * Initialize coefficient buffer controller. + * + * Each passed coefficient array must be the right size for that + * coefficient: width_in_data_units wide and height_in_data_units high, + * with unitheight at least v_samp_factor. + */ + +LOCAL(void) +transencode_coef_controller (j_compress_ptr cinfo, + jvirt_barray_ptr * coef_arrays) +{ + j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; + c_coef_ptr coef; + JBLOCKROW buffer; + int i; + + coef = (c_coef_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(c_coef_controller)); + lossyc->coef_private = (struct jpeg_c_coef_controller *) coef; + + /* Save pointer to virtual arrays */ + coef->whole_image = coef_arrays; + + /* Allocate and pre-zero space for dummy DCT blocks. */ + buffer = (JBLOCKROW) + (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, + C_MAX_DATA_UNITS_IN_MCU * SIZEOF(JBLOCK)); + jzero_far((void FAR *) buffer, C_MAX_DATA_UNITS_IN_MCU * SIZEOF(JBLOCK)); + for (i = 0; i < C_MAX_DATA_UNITS_IN_MCU; i++) { + coef->dummy_buffer[i] = buffer + i; + } +} + + +/* + * Initialize the transencoer codec. + * This is called only once, during master selection. + */ + +LOCAL(void) +transencode_codec (j_compress_ptr cinfo, + jvirt_barray_ptr * coef_arrays) +{ + j_lossy_c_ptr lossyc; + + /* Create subobject in permanent pool */ + lossyc = (j_lossy_c_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(jpeg_lossy_c_codec)); + cinfo->codec = (struct jpeg_c_codec *) lossyc; + + /* Initialize sub-modules */ + + /* Entropy encoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { + jinit_arith_encoder(cinfo); + } else { + if (cinfo->process == JPROC_PROGRESSIVE) { +#ifdef C_PROGRESSIVE_SUPPORTED + jinit_phuff_encoder(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else + jinit_shuff_encoder(cinfo); + } + + /* We need a special coefficient buffer controller. */ + transencode_coef_controller(cinfo, coef_arrays); + + /* Initialize method pointers */ + lossyc->pub.start_pass = start_pass_coef; + lossyc->pub.compress_data = compress_output; +} diff --git a/src/gdcmjpeg/jdapimin.c b/src/gdcmjpeg/jdapimin.c new file mode 100644 index 00000000..d13a1540 --- /dev/null +++ b/src/gdcmjpeg/jdapimin.c @@ -0,0 +1,401 @@ +/* + * jdapimin.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains application interface code for the decompression half + * of the JPEG library. These are the "minimum" API routines that may be + * needed in either the normal full-decompression case or the + * transcoding-only case. + * + * Most of the routines intended to be called directly by an application + * are in this file or in jdapistd.c. But also see jcomapi.c for routines + * shared by compression and decompression, and jdtrans.c for the transcoding + * case. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Initialization of a JPEG decompression object. + * The error manager must already be set up (in case memory manager fails). + */ + +GLOBAL(void) +jpeg_CreateDecompress (j_decompress_ptr cinfo, int version, size_t structsize) +{ + int i; + + /* Guard against version mismatches between library and caller. */ + cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */ + if (version != JPEG_LIB_VERSION) + ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version); + if (structsize != SIZEOF(struct jpeg_decompress_struct)) + ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, + (int) SIZEOF(struct jpeg_decompress_struct), (int) structsize); + + /* For debugging purposes, we zero the whole master structure. + * But the application has already set the err pointer, and may have set + * client_data, so we have to save and restore those fields. + * Note: if application hasn't set client_data, tools like Purify may + * complain here. + */ + { + struct jpeg_error_mgr * err = cinfo->err; + void * client_data = cinfo->client_data; /* ignore Purify complaint here */ + MEMZERO(cinfo, SIZEOF(struct jpeg_decompress_struct)); + cinfo->err = err; + cinfo->client_data = client_data; + } + cinfo->is_decompressor = TRUE; + + /* Initialize a memory manager instance for this object */ + jinit_memory_mgr((j_common_ptr) cinfo); + + /* Zero out pointers to permanent structures. */ + cinfo->progress = NULL; + cinfo->src = NULL; + + for (i = 0; i < NUM_QUANT_TBLS; i++) + cinfo->quant_tbl_ptrs[i] = NULL; + + for (i = 0; i < NUM_HUFF_TBLS; i++) { + cinfo->dc_huff_tbl_ptrs[i] = NULL; + cinfo->ac_huff_tbl_ptrs[i] = NULL; + } + + /* Initialize marker processor so application can override methods + * for COM, APPn markers before calling jpeg_read_header. + */ + cinfo->marker_list = NULL; + jinit_marker_reader(cinfo); + + /* And initialize the overall input controller. */ + jinit_input_controller(cinfo); + + /* OK, I'm ready */ + cinfo->global_state = DSTATE_START; +} + + +/* + * Destruction of a JPEG decompression object + */ + +GLOBAL(void) +jpeg_destroy_decompress (j_decompress_ptr cinfo) +{ + jpeg_destroy((j_common_ptr) cinfo); /* use common routine */ +} + + +/* + * Abort processing of a JPEG decompression operation, + * but don't destroy the object itself. + */ + +GLOBAL(void) +jpeg_abort_decompress (j_decompress_ptr cinfo) +{ + jpeg_abort((j_common_ptr) cinfo); /* use common routine */ +} + + +/* + * Set default decompression parameters. + */ + +LOCAL(void) +default_decompress_parms (j_decompress_ptr cinfo) +{ + /* Guess the input colorspace, and set output colorspace accordingly. */ + /* (Wish JPEG committee had provided a real way to specify this...) */ + /* Note application may override our guesses. */ + switch (cinfo->num_components) { + case 1: + cinfo->jpeg_color_space = JCS_GRAYSCALE; + cinfo->out_color_space = JCS_GRAYSCALE; + break; + + case 3: + if (cinfo->saw_JFIF_marker) { + cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */ + } else if (cinfo->saw_Adobe_marker) { + switch (cinfo->Adobe_transform) { + case 0: + cinfo->jpeg_color_space = JCS_RGB; + break; + case 1: + cinfo->jpeg_color_space = JCS_YCbCr; + break; + default: + WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform); + cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */ + break; + } + } else { + /* Saw no special markers, try to guess from the component IDs */ + int cid0 = cinfo->comp_info[0].component_id; + int cid1 = cinfo->comp_info[1].component_id; + int cid2 = cinfo->comp_info[2].component_id; + + if (cid0 == 1 && cid1 == 2 && cid2 == 3) + cinfo->jpeg_color_space = JCS_YCbCr; /* assume JFIF w/out marker */ + else if (cid0 == 82 && cid1 == 71 && cid2 == 66) + cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */ + else { + if (cinfo->process == JPROC_LOSSLESS) { + TRACEMS3(cinfo, 1, JTRC_UNKNOWN_LOSSLESS_IDS, cid0, cid1, cid2); + cinfo->jpeg_color_space = JCS_RGB; /* assume it's RGB */ + } + else { /* Lossy processes */ + TRACEMS3(cinfo, 1, JTRC_UNKNOWN_LOSSY_IDS, cid0, cid1, cid2); + cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */ + } + } + } + /* Always guess RGB is proper output colorspace. */ + cinfo->out_color_space = JCS_RGB; + break; + + case 4: + if (cinfo->saw_Adobe_marker) { + switch (cinfo->Adobe_transform) { + case 0: + cinfo->jpeg_color_space = JCS_CMYK; + break; + case 2: + cinfo->jpeg_color_space = JCS_YCCK; + break; + default: + WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform); + cinfo->jpeg_color_space = JCS_YCCK; /* assume it's YCCK */ + break; + } + } else { + /* No special markers, assume straight CMYK. */ + cinfo->jpeg_color_space = JCS_CMYK; + } + cinfo->out_color_space = JCS_CMYK; + break; + + default: + cinfo->jpeg_color_space = JCS_UNKNOWN; + cinfo->out_color_space = JCS_UNKNOWN; + break; + } + + /* Set defaults for other decompression parameters. */ + cinfo->scale_num = 1; /* 1:1 scaling */ + cinfo->scale_denom = 1; + cinfo->output_gamma = 1.0; + cinfo->buffered_image = FALSE; + cinfo->raw_data_out = FALSE; + cinfo->dct_method = JDCT_DEFAULT; + cinfo->do_fancy_upsampling = TRUE; + cinfo->do_block_smoothing = TRUE; + cinfo->quantize_colors = FALSE; + /* We set these in case application only sets quantize_colors. */ + cinfo->dither_mode = JDITHER_FS; +#ifdef QUANT_2PASS_SUPPORTED + cinfo->two_pass_quantize = TRUE; +#else + cinfo->two_pass_quantize = FALSE; +#endif + cinfo->desired_number_of_colors = 256; + cinfo->colormap = NULL; + /* Initialize for no mode change in buffered-image mode. */ + cinfo->enable_1pass_quant = FALSE; + cinfo->enable_external_quant = FALSE; + cinfo->enable_2pass_quant = FALSE; +} + + +/* + * Decompression startup: read start of JPEG datastream to see what's there. + * Need only initialize JPEG object and supply a data source before calling. + * + * This routine will read as far as the first SOS marker (ie, actual start of + * compressed data), and will save all tables and parameters in the JPEG + * object. It will also initialize the decompression parameters to default + * values, and finally return JPEG_HEADER_OK. On return, the application may + * adjust the decompression parameters and then call jpeg_start_decompress. + * (Or, if the application only wanted to determine the image parameters, + * the data need not be decompressed. In that case, call jpeg_abort or + * jpeg_destroy to release any temporary space.) + * If an abbreviated (tables only) datastream is presented, the routine will + * return JPEG_HEADER_TABLES_ONLY upon reaching EOI. The application may then + * re-use the JPEG object to read the abbreviated image datastream(s). + * It is unnecessary (but OK) to call jpeg_abort in this case. + * The JPEG_SUSPENDED return code only occurs if the data source module + * requests suspension of the decompressor. In this case the application + * should load more source data and then re-call jpeg_read_header to resume + * processing. + * If a non-suspending data source is used and require_image is TRUE, then the + * return code need not be inspected since only JPEG_HEADER_OK is possible. + * + * This routine is now just a front end to jpeg_consume_input, with some + * extra error checking. + */ + +GLOBAL(int) +jpeg_read_header (j_decompress_ptr cinfo, boolean require_image) +{ + int retcode; + + if (cinfo->global_state != DSTATE_START && + cinfo->global_state != DSTATE_INHEADER) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + retcode = jpeg_consume_input(cinfo); + + switch (retcode) { + case JPEG_REACHED_SOS: + retcode = JPEG_HEADER_OK; + break; + case JPEG_REACHED_EOI: + if (require_image) /* Complain if application wanted an image */ + ERREXIT(cinfo, JERR_NO_IMAGE); + /* Reset to start state; it would be safer to require the application to + * call jpeg_abort, but we can't change it now for compatibility reasons. + * A side effect is to free any temporary memory (there shouldn't be any). + */ + jpeg_abort((j_common_ptr) cinfo); /* sets state = DSTATE_START */ + retcode = JPEG_HEADER_TABLES_ONLY; + break; + case JPEG_SUSPENDED: + /* no work */ + break; + } + + return retcode; +} + + +/* + * Consume data in advance of what the decompressor requires. + * This can be called at any time once the decompressor object has + * been created and a data source has been set up. + * + * This routine is essentially a state machine that handles a couple + * of critical state-transition actions, namely initial setup and + * transition from header scanning to ready-for-start_decompress. + * All the actual input is done via the input controller's consume_input + * method. + */ + +GLOBAL(int) +jpeg_consume_input (j_decompress_ptr cinfo) +{ + int retcode = JPEG_SUSPENDED; + + /* NB: every possible DSTATE value should be listed in this switch */ + switch (cinfo->global_state) { + case DSTATE_START: + /* Start-of-datastream actions: reset appropriate modules */ + (*cinfo->inputctl->reset_input_controller) (cinfo); + /* Initialize application's data source module */ + (*cinfo->src->init_source) (cinfo); + cinfo->global_state = DSTATE_INHEADER; + /*FALLTHROUGH*/ + case DSTATE_INHEADER: + retcode = (*cinfo->inputctl->consume_input) (cinfo); + if (retcode == JPEG_REACHED_SOS) { /* Found SOS, prepare to decompress */ + /* Set up default parameters based on header data */ + default_decompress_parms(cinfo); + /* Set global state: ready for start_decompress */ + cinfo->global_state = DSTATE_READY; + } + break; + case DSTATE_READY: + /* Can't advance past first SOS until start_decompress is called */ + retcode = JPEG_REACHED_SOS; + break; + case DSTATE_PRELOAD: + case DSTATE_PRESCAN: + case DSTATE_SCANNING: + case DSTATE_RAW_OK: + case DSTATE_BUFIMAGE: + case DSTATE_BUFPOST: + case DSTATE_STOPPING: + retcode = (*cinfo->inputctl->consume_input) (cinfo); + break; + default: + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + } + return retcode; +} + + +/* + * Have we finished reading the input file? + */ + +GLOBAL(boolean) +jpeg_input_complete (j_decompress_ptr cinfo) +{ + /* Check for valid jpeg object */ + if (cinfo->global_state < DSTATE_START || + cinfo->global_state > DSTATE_STOPPING) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + return cinfo->inputctl->eoi_reached; +} + + +/* + * Is there more than one scan? + */ + +GLOBAL(boolean) +jpeg_has_multiple_scans (j_decompress_ptr cinfo) +{ + /* Only valid after jpeg_read_header completes */ + if (cinfo->global_state < DSTATE_READY || + cinfo->global_state > DSTATE_STOPPING) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + return cinfo->inputctl->has_multiple_scans; +} + + +/* + * Finish JPEG decompression. + * + * This will normally just verify the file trailer and release temp storage. + * + * Returns FALSE if suspended. The return value need be inspected only if + * a suspending data source is used. + */ + +GLOBAL(boolean) +jpeg_finish_decompress (j_decompress_ptr cinfo) +{ + if ((cinfo->global_state == DSTATE_SCANNING || + cinfo->global_state == DSTATE_RAW_OK) && ! cinfo->buffered_image) { + /* Terminate final pass of non-buffered mode */ + if (cinfo->output_scanline < cinfo->output_height) + ERREXIT(cinfo, JERR_TOO_LITTLE_DATA); + (*cinfo->master->finish_output_pass) (cinfo); + cinfo->global_state = DSTATE_STOPPING; + } else if (cinfo->global_state == DSTATE_BUFIMAGE) { + /* Finishing after a buffered-image operation */ + cinfo->global_state = DSTATE_STOPPING; + } else if (cinfo->global_state != DSTATE_STOPPING) { + /* STOPPING = repeat call after a suspension, anything else is error */ + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + } + /* Read until EOI */ + while (! cinfo->inputctl->eoi_reached) { + if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED) + return FALSE; /* Suspend, come back later */ + } + /* Do final cleanup */ + (*cinfo->src->term_source) (cinfo); + /* We can use jpeg_abort to release memory and reset global_state */ + jpeg_abort((j_common_ptr) cinfo); + return TRUE; +} diff --git a/src/gdcmjpeg/jdapistd.c b/src/gdcmjpeg/jdapistd.c new file mode 100644 index 00000000..4cc36d71 --- /dev/null +++ b/src/gdcmjpeg/jdapistd.c @@ -0,0 +1,275 @@ +/* + * jdapistd.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains application interface code for the decompression half + * of the JPEG library. These are the "standard" API routines that are + * used in the normal full-decompression case. They are not used by a + * transcoding-only application. Note that if an application links in + * jpeg_start_decompress, it will end up linking in the entire decompressor. + * We thus must separate this file from jdapimin.c to avoid linking the + * whole decompression library into a transcoder. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Forward declarations */ +LOCAL(boolean) output_pass_setup JPP((j_decompress_ptr cinfo)); + + +/* + * Decompression initialization. + * jpeg_read_header must be completed before calling this. + * + * If a multipass operating mode was selected, this will do all but the + * last pass, and thus may take a great deal of time. + * + * Returns FALSE if suspended. The return value need be inspected only if + * a suspending data source is used. + */ + +GLOBAL(boolean) +jpeg_start_decompress (j_decompress_ptr cinfo) +{ + if (cinfo->global_state == DSTATE_READY) { + /* First call: initialize master control, select active modules */ + jinit_master_decompress(cinfo); + if (cinfo->buffered_image) { + /* No more work here; expecting jpeg_start_output next */ + cinfo->global_state = DSTATE_BUFIMAGE; + return TRUE; + } + cinfo->global_state = DSTATE_PRELOAD; + } + if (cinfo->global_state == DSTATE_PRELOAD) { + /* If file has multiple scans, absorb them all into the coef buffer */ + if (cinfo->inputctl->has_multiple_scans) { +#ifdef D_MULTISCAN_FILES_SUPPORTED + for (;;) { + int retcode; + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + /* Absorb some more input */ + retcode = (*cinfo->inputctl->consume_input) (cinfo); + if (retcode == JPEG_SUSPENDED) + return FALSE; + if (retcode == JPEG_REACHED_EOI) + break; + /* Advance progress counter if appropriate */ + if (cinfo->progress != NULL && + (retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) { + if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) { + /* jdmaster underestimated number of scans; ratchet up one scan */ + cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows; + } + } + } +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif /* D_MULTISCAN_FILES_SUPPORTED */ + } + cinfo->output_scan_number = cinfo->input_scan_number; + } else if (cinfo->global_state != DSTATE_PRESCAN) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + /* Perform any dummy output passes, and set up for the final pass */ + return output_pass_setup(cinfo); +} + + +/* + * Set up for an output pass, and perform any dummy pass(es) needed. + * Common subroutine for jpeg_start_decompress and jpeg_start_output. + * Entry: global_state = DSTATE_PRESCAN only if previously suspended. + * Exit: If done, returns TRUE and sets global_state for proper output mode. + * If suspended, returns FALSE and sets global_state = DSTATE_PRESCAN. + */ + +LOCAL(boolean) +output_pass_setup (j_decompress_ptr cinfo) +{ + if (cinfo->global_state != DSTATE_PRESCAN) { + /* First call: do pass setup */ + (*cinfo->master->prepare_for_output_pass) (cinfo); + cinfo->output_scanline = 0; + cinfo->global_state = DSTATE_PRESCAN; + } + /* Loop over any required dummy passes */ + while (cinfo->master->is_dummy_pass) { +#ifdef QUANT_2PASS_SUPPORTED + /* Crank through the dummy pass */ + while (cinfo->output_scanline < cinfo->output_height) { + JDIMENSION last_scanline; + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) { + cinfo->progress->pass_counter = (long) cinfo->output_scanline; + cinfo->progress->pass_limit = (long) cinfo->output_height; + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + } + /* Process some data */ + last_scanline = cinfo->output_scanline; + (*cinfo->main->process_data) (cinfo, (JSAMPARRAY) NULL, + &cinfo->output_scanline, (JDIMENSION) 0); + if (cinfo->output_scanline == last_scanline) + return FALSE; /* No progress made, must suspend */ + } + /* Finish up dummy pass, and set up for another one */ + (*cinfo->master->finish_output_pass) (cinfo); + (*cinfo->master->prepare_for_output_pass) (cinfo); + cinfo->output_scanline = 0; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif /* QUANT_2PASS_SUPPORTED */ + } + /* Ready for application to drive output pass through + * jpeg_read_scanlines or jpeg_read_raw_data. + */ + cinfo->global_state = cinfo->raw_data_out ? DSTATE_RAW_OK : DSTATE_SCANNING; + return TRUE; +} + + +/* + * Read some scanlines of data from the JPEG decompressor. + * + * The return value will be the number of lines actually read. + * This may be less than the number requested in several cases, + * including bottom of image, data source suspension, and operating + * modes that emit multiple scanlines at a time. + * + * Note: we warn about excess calls to jpeg_read_scanlines() since + * this likely signals an application programmer error. However, + * an oversize buffer (max_lines > scanlines remaining) is not an error. + */ + +GLOBAL(JDIMENSION) +jpeg_read_scanlines (j_decompress_ptr cinfo, JSAMPARRAY scanlines, + JDIMENSION max_lines) +{ + JDIMENSION row_ctr; + + if (cinfo->global_state != DSTATE_SCANNING) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + if (cinfo->output_scanline >= cinfo->output_height) { + WARNMS(cinfo, JWRN_TOO_MUCH_DATA); + return 0; + } + + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) { + cinfo->progress->pass_counter = (long) cinfo->output_scanline; + cinfo->progress->pass_limit = (long) cinfo->output_height; + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + } + + /* Process some data */ + row_ctr = 0; + (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, max_lines); + cinfo->output_scanline += row_ctr; + return row_ctr; +} + + +/* + * Alternate entry point to read raw data. + * Processes exactly one iMCU row per call, unless suspended. + */ + +GLOBAL(JDIMENSION) +jpeg_read_raw_data (j_decompress_ptr cinfo, JSAMPIMAGE data, + JDIMENSION max_lines) +{ + JDIMENSION lines_per_iMCU_row; + + if (cinfo->global_state != DSTATE_RAW_OK) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + if (cinfo->output_scanline >= cinfo->output_height) { + WARNMS(cinfo, JWRN_TOO_MUCH_DATA); + return 0; + } + + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) { + cinfo->progress->pass_counter = (long) cinfo->output_scanline; + cinfo->progress->pass_limit = (long) cinfo->output_height; + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + } + + /* Verify that at least one iMCU row can be returned. */ + lines_per_iMCU_row = cinfo->max_v_samp_factor * cinfo->min_codec_data_unit; + if (max_lines < lines_per_iMCU_row) + ERREXIT(cinfo, JERR_BUFFER_SIZE); + + /* Decompress directly into user's buffer. */ + if (! (*cinfo->codec->decompress_data) (cinfo, data)) + return 0; /* suspension forced, can do nothing more */ + + /* OK, we processed one iMCU row. */ + cinfo->output_scanline += lines_per_iMCU_row; + return lines_per_iMCU_row; +} + + +/* Additional entry points for buffered-image mode. */ + +#ifdef D_MULTISCAN_FILES_SUPPORTED + +/* + * Initialize for an output pass in buffered-image mode. + */ + +GLOBAL(boolean) +jpeg_start_output (j_decompress_ptr cinfo, int scan_number) +{ + if (cinfo->global_state != DSTATE_BUFIMAGE && + cinfo->global_state != DSTATE_PRESCAN) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + /* Limit scan number to valid range */ + if (scan_number <= 0) + scan_number = 1; + if (cinfo->inputctl->eoi_reached && + scan_number > cinfo->input_scan_number) + scan_number = cinfo->input_scan_number; + cinfo->output_scan_number = scan_number; + /* Perform any dummy output passes, and set up for the real pass */ + return output_pass_setup(cinfo); +} + + +/* + * Finish up after an output pass in buffered-image mode. + * + * Returns FALSE if suspended. The return value need be inspected only if + * a suspending data source is used. + */ + +GLOBAL(boolean) +jpeg_finish_output (j_decompress_ptr cinfo) +{ + if ((cinfo->global_state == DSTATE_SCANNING || + cinfo->global_state == DSTATE_RAW_OK) && cinfo->buffered_image) { + /* Terminate this pass. */ + /* We do not require the whole pass to have been completed. */ + (*cinfo->master->finish_output_pass) (cinfo); + cinfo->global_state = DSTATE_BUFPOST; + } else if (cinfo->global_state != DSTATE_BUFPOST) { + /* BUFPOST = repeat call after a suspension, anything else is error */ + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + } + /* Read markers looking for SOS or EOI */ + while (cinfo->input_scan_number <= cinfo->output_scan_number && + ! cinfo->inputctl->eoi_reached) { + if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED) + return FALSE; /* Suspend, come back later */ + } + cinfo->global_state = DSTATE_BUFIMAGE; + return TRUE; +} + +#endif /* D_MULTISCAN_FILES_SUPPORTED */ diff --git a/src/gdcmjpeg/jdarith.c b/src/gdcmjpeg/jdarith.c new file mode 100644 index 00000000..52eb79d7 --- /dev/null +++ b/src/gdcmjpeg/jdarith.c @@ -0,0 +1,24 @@ +/* + * jdarith.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file holds place for arithmetic entropy decoding routines. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * Module initialization routine for arithmetic entropy decoding. + */ + +GLOBAL(void) +jinit_arith_decoder (j_decompress_ptr cinfo) +{ + ERREXIT(cinfo, JERR_ARITH_NOTIMPL); +} diff --git a/src/gdcmjpeg/jdatadst.c b/src/gdcmjpeg/jdatadst.c new file mode 100644 index 00000000..88d859d2 --- /dev/null +++ b/src/gdcmjpeg/jdatadst.c @@ -0,0 +1,151 @@ +/* + * jdatadst.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains compression data destination routines for the case of + * emitting JPEG data to a file (or any stdio stream). While these routines + * are sufficient for most applications, some will want to use a different + * destination manager. + * IMPORTANT: we assume that fwrite() will correctly transcribe an array of + * JOCTETs into 8-bit-wide elements on external storage. If char is wider + * than 8 bits on your machine, you may need to do some tweaking. + */ + +/* this is not a core library module, so it doesn't define JPEG_INTERNALS */ +#include "jinclude.h" +#include "jpeglib.h" +#include "jerror.h" + + +/* Expanded data destination object for stdio output */ + +typedef struct { + struct jpeg_destination_mgr pub; /* public fields */ + + FILE * outfile; /* target stream */ + JOCTET * buffer; /* start of buffer */ +} my_destination_mgr; + +typedef my_destination_mgr * my_dest_ptr; + +#define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */ + + +/* + * Initialize destination --- called by jpeg_start_compress + * before any data is actually written. + */ + +METHODDEF(void) +init_destination (j_compress_ptr cinfo) +{ + my_dest_ptr dest = (my_dest_ptr) cinfo->dest; + + /* Allocate the output buffer --- it will be released when done with image */ + dest->buffer = (JOCTET *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + OUTPUT_BUF_SIZE * SIZEOF(JOCTET)); + + dest->pub.next_output_byte = dest->buffer; + dest->pub.free_in_buffer = OUTPUT_BUF_SIZE; +} + + +/* + * Empty the output buffer --- called whenever buffer fills up. + * + * In typical applications, this should write the entire output buffer + * (ignoring the current state of next_output_byte & free_in_buffer), + * reset the pointer & count to the start of the buffer, and return TRUE + * indicating that the buffer has been dumped. + * + * In applications that need to be able to suspend compression due to output + * overrun, a FALSE return indicates that the buffer cannot be emptied now. + * In this situation, the compressor will return to its caller (possibly with + * an indication that it has not accepted all the supplied scanlines). The + * application should resume compression after it has made more room in the + * output buffer. Note that there are substantial restrictions on the use of + * suspension --- see the documentation. + * + * When suspending, the compressor will back up to a convenient restart point + * (typically the start of the current MCU). next_output_byte & free_in_buffer + * indicate where the restart point will be if the current call returns FALSE. + * Data beyond this point will be regenerated after resumption, so do not + * write it out when emptying the buffer externally. + */ + +METHODDEF(boolean) +empty_output_buffer (j_compress_ptr cinfo) +{ + my_dest_ptr dest = (my_dest_ptr) cinfo->dest; + + if (JFWRITE(dest->outfile, dest->buffer, OUTPUT_BUF_SIZE) != + (size_t) OUTPUT_BUF_SIZE) + ERREXIT(cinfo, JERR_FILE_WRITE); + + dest->pub.next_output_byte = dest->buffer; + dest->pub.free_in_buffer = OUTPUT_BUF_SIZE; + + return TRUE; +} + + +/* + * Terminate destination --- called by jpeg_finish_compress + * after all data has been written. Usually needs to flush buffer. + * + * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding + * application must deal with any cleanup that should happen even + * for error exit. + */ + +METHODDEF(void) +term_destination (j_compress_ptr cinfo) +{ + my_dest_ptr dest = (my_dest_ptr) cinfo->dest; + size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer; + + /* Write any data remaining in the buffer */ + if (datacount > 0) { + if (JFWRITE(dest->outfile, dest->buffer, datacount) != datacount) + ERREXIT(cinfo, JERR_FILE_WRITE); + } + fflush(dest->outfile); + /* Make sure we wrote the output file OK */ + if (ferror(dest->outfile)) + ERREXIT(cinfo, JERR_FILE_WRITE); +} + + +/* + * Prepare for output to a stdio stream. + * The caller must have already opened the stream, and is responsible + * for closing it after finishing compression. + */ + +GLOBAL(void) +jpeg_stdio_dest (j_compress_ptr cinfo, FILE * outfile) +{ + my_dest_ptr dest; + + /* The destination object is made permanent so that multiple JPEG images + * can be written to the same file without re-executing jpeg_stdio_dest. + * This makes it dangerous to use this manager and a different destination + * manager serially with the same JPEG object, because their private object + * sizes may be different. Caveat programmer. + */ + if (cinfo->dest == NULL) { /* first time for this JPEG object? */ + cinfo->dest = (struct jpeg_destination_mgr *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(my_destination_mgr)); + } + + dest = (my_dest_ptr) cinfo->dest; + dest->pub.init_destination = init_destination; + dest->pub.empty_output_buffer = empty_output_buffer; + dest->pub.term_destination = term_destination; + dest->outfile = outfile; +} diff --git a/src/gdcmjpeg/jdatasrc.c b/src/gdcmjpeg/jdatasrc.c new file mode 100644 index 00000000..531c90b3 --- /dev/null +++ b/src/gdcmjpeg/jdatasrc.c @@ -0,0 +1,213 @@ +/* + * jdatasrc.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains decompression data source routines for the case of + * reading JPEG data from a file (or any stdio stream). While these routines + * are sufficient for most applications, some will want to use a different + * source manager. + * IMPORTANT: we assume that fread() will correctly transcribe an array of + * JOCTETs from 8-bit-wide elements on external storage. If char is wider + * than 8 bits on your machine, you may need to do some tweaking. + */ + +/* this is not a core library module, so it doesn't define JPEG_INTERNALS */ +#include "jinclude.h" +#include "jpeglib.h" +#include "jerror.h" + + +/* Expanded data source object for stdio input */ + +typedef struct { + struct jpeg_source_mgr pub; /* public fields */ + + FILE * infile; /* source stream */ + JOCTET * buffer; /* start of buffer */ + boolean start_of_file; /* have we gotten any data yet? */ +} my_source_mgr; + +typedef my_source_mgr * my_src_ptr; + +#define INPUT_BUF_SIZE 4096 /* choose an efficiently fread'able size */ + + +/* + * Initialize source --- called by jpeg_read_header + * before any data is actually read. + */ + +METHODDEF(void) +init_source (j_decompress_ptr cinfo) +{ + my_src_ptr src = (my_src_ptr) cinfo->src; + + /* We reset the empty-input-file flag for each image, + * but we don't clear the input buffer. + * This is correct behavior for reading a series of images from one source. + */ + src->start_of_file = TRUE; +} + + +/* + * Fill the input buffer --- called whenever buffer is emptied. + * + * In typical applications, this should read fresh data into the buffer + * (ignoring the current state of next_input_byte & bytes_in_buffer), + * reset the pointer & count to the start of the buffer, and return TRUE + * indicating that the buffer has been reloaded. It is not necessary to + * fill the buffer entirely, only to obtain at least one more byte. + * + * There is no such thing as an EOF return. If the end of the file has been + * reached, the routine has a choice of ERREXIT() or inserting fake data into + * the buffer. In most cases, generating a warning message and inserting a + * fake EOI marker is the best course of action --- this will allow the + * decompressor to output however much of the image is there. However, + * the resulting error message is misleading if the real problem is an empty + * input file, so we handle that case specially. + * + * In applications that need to be able to suspend compression due to input + * not being available yet, a FALSE return indicates that no more data can be + * obtained right now, but more may be forthcoming later. In this situation, + * the decompressor will return to its caller (with an indication of the + * number of scanlines it has read, if any). The application should resume + * decompression after it has loaded more data into the input buffer. Note + * that there are substantial restrictions on the use of suspension --- see + * the documentation. + * + * When suspending, the decompressor will back up to a convenient restart point + * (typically the start of the current MCU). next_input_byte & bytes_in_buffer + * indicate where the restart point will be if the current call returns FALSE. + * Data beyond this point must be rescanned after resumption, so move it to + * the front of the buffer rather than discarding it. + */ + +METHODDEF(boolean) +fill_input_buffer (j_decompress_ptr cinfo) +{ + my_src_ptr src = (my_src_ptr) cinfo->src; + size_t nbytes; + + nbytes = JFREAD(src->infile, src->buffer, INPUT_BUF_SIZE); + + if (nbytes <= 0) { + if (src->start_of_file) /* Treat empty input file as fatal error */ + ERREXIT(cinfo, JERR_INPUT_EMPTY); + WARNMS(cinfo, JWRN_JPEG_EOF); + /* Insert a fake EOI marker */ + src->buffer[0] = (JOCTET) 0xFF; + src->buffer[1] = (JOCTET) JPEG_EOI; + nbytes = 2; + } + + src->pub.next_input_byte = src->buffer; + src->pub.bytes_in_buffer = nbytes; + src->start_of_file = FALSE; + + return TRUE; +} + + +/* + * Skip data --- used to skip over a potentially large amount of + * uninteresting data (such as an APPn marker). + * + * Writers of suspendable-input applications must note that skip_input_data + * is not granted the right to give a suspension return. If the skip extends + * beyond the data currently in the buffer, the buffer can be marked empty so + * that the next read will cause a fill_input_buffer call that can suspend. + * Arranging for additional bytes to be discarded before reloading the input + * buffer is the application writer's problem. + */ + +METHODDEF(void) +skip_input_data (j_decompress_ptr cinfo, long num_bytes) +{ + my_src_ptr src = (my_src_ptr) cinfo->src; + + /* Just a dumb implementation for now. Could use fseek() except + * it doesn't work on pipes. Not clear that being smart is worth + * any trouble anyway --- large skips are infrequent. + */ + if (num_bytes > 0) { + while (num_bytes > (long) src->pub.bytes_in_buffer) { + num_bytes -= (long) src->pub.bytes_in_buffer; + (void) fill_input_buffer(cinfo); + /* note we assume that fill_input_buffer will never return FALSE, + * so suspension need not be handled. + */ + } + src->pub.next_input_byte += (size_t) num_bytes; + src->pub.bytes_in_buffer -= (size_t) num_bytes; + } +} + + +/* + * An additional method that can be provided by data source modules is the + * resync_to_restart method for error recovery in the presence of RST markers. + * For the moment, this source module just uses the default resync method + * provided by the JPEG library. That method assumes that no backtracking + * is possible. + */ + + +/* + * Terminate source --- called by jpeg_finish_decompress + * after all data has been read. Often a no-op. + * + * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding + * application must deal with any cleanup that should happen even + * for error exit. + */ + +METHODDEF(void) +term_source (j_decompress_ptr cinfo) +{ + (void)cinfo; + /* no work necessary here */ +} + + +/* + * Prepare for input from a stdio stream. + * The caller must have already opened the stream, and is responsible + * for closing it after finishing decompression. + */ + +GLOBAL(void) +jpeg_stdio_src (j_decompress_ptr cinfo, FILE * infile) +{ + my_src_ptr src; + + /* The source object and input buffer are made permanent so that a series + * of JPEG images can be read from the same file by calling jpeg_stdio_src + * only before the first one. (If we discarded the buffer at the end of + * one image, we'd likely lose the start of the next one.) + * This makes it unsafe to use this manager and a different source + * manager serially with the same JPEG object. Caveat programmer. + */ + if (cinfo->src == NULL) { /* first time for this JPEG object? */ + cinfo->src = (struct jpeg_source_mgr *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(my_source_mgr)); + src = (my_src_ptr) cinfo->src; + src->buffer = (JOCTET *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + INPUT_BUF_SIZE * SIZEOF(JOCTET)); + } + + src = (my_src_ptr) cinfo->src; + src->pub.init_source = init_source; + src->pub.fill_input_buffer = fill_input_buffer; + src->pub.skip_input_data = skip_input_data; + src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */ + src->pub.term_source = term_source; + src->infile = infile; + src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */ + src->pub.next_input_byte = NULL; /* until buffer loaded */ +} diff --git a/src/gdcmjpeg/jdcoefct.c b/src/gdcmjpeg/jdcoefct.c new file mode 100644 index 00000000..2e5ec110 --- /dev/null +++ b/src/gdcmjpeg/jdcoefct.c @@ -0,0 +1,744 @@ +/* + * jdcoefct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the coefficient buffer controller for decompression. + * This controller is the top level of the lossy JPEG decompressor proper. + * The coefficient buffer lies between entropy decoding and inverse-DCT steps. + * + * In buffered-image mode, this controller is the interface between + * input-oriented processing and output-oriented processing. + * Also, the input side (only) is used when reading a file for transcoding. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" + +/* Block smoothing is only applicable for progressive JPEG, so: */ +#ifndef D_PROGRESSIVE_SUPPORTED +#undef BLOCK_SMOOTHING_SUPPORTED +#endif + +/* Private buffer controller object */ + +typedef struct { + /* These variables keep track of the current location of the input side. */ + /* cinfo->input_iMCU_row is also used for this. */ + JDIMENSION MCU_ctr; /* counts MCUs processed in current row */ + int MCU_vert_offset; /* counts MCU rows within iMCU row */ + int MCU_rows_per_iMCU_row; /* number of such rows needed */ + + /* The output side's location is represented by cinfo->output_iMCU_row. */ + + /* In single-pass modes, it's sufficient to buffer just one MCU. + * We allocate a workspace of D_MAX_DATA_UNITS_IN_MCU coefficient blocks, + * and let the entropy decoder write into that workspace each time. + * (On 80x86, the workspace is FAR even though it's not really very big; + * this is to keep the module interfaces unchanged when a large coefficient + * buffer is necessary.) + * In multi-pass modes, this array points to the current MCU's blocks + * within the virtual arrays; it is used only by the input side. + */ + JBLOCKROW MCU_buffer[D_MAX_DATA_UNITS_IN_MCU]; + +#ifdef D_MULTISCAN_FILES_SUPPORTED + /* In multi-pass modes, we need a virtual block array for each component. */ + jvirt_barray_ptr whole_image[MAX_COMPONENTS]; +#endif + +#ifdef BLOCK_SMOOTHING_SUPPORTED + /* When doing block smoothing, we latch coefficient Al values here */ + int * coef_bits_latch; +#define SAVED_COEFS 6 /* we save coef_bits[0..5] */ +#endif +} d_coef_controller; + +typedef d_coef_controller * d_coef_ptr; + +/* Forward declarations */ +METHODDEF(int) decompress_onepass + JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); +#ifdef D_MULTISCAN_FILES_SUPPORTED +METHODDEF(int) decompress_data + JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); +#endif +#ifdef BLOCK_SMOOTHING_SUPPORTED +LOCAL(boolean) smoothing_ok JPP((j_decompress_ptr cinfo)); +METHODDEF(int) decompress_smooth_data + JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); +#endif + + +LOCAL(void) +start_iMCU_row (j_decompress_ptr cinfo) +/* Reset within-iMCU-row counters for a new row (input side) */ +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; + + /* In an interleaved scan, an MCU row is the same as an iMCU row. + * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows. + * But at the bottom of the image, process only what's left. + */ + if (cinfo->comps_in_scan > 1) { + coef->MCU_rows_per_iMCU_row = 1; + } else { + if (cinfo->input_iMCU_row < (cinfo->total_iMCU_rows-1)) + coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor; + else + coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height; + } + + coef->MCU_ctr = 0; + coef->MCU_vert_offset = 0; +} + + +/* + * Initialize for an input processing pass. + */ + +METHODDEF(void) +start_input_pass (j_decompress_ptr cinfo) +{ + cinfo->input_iMCU_row = 0; + start_iMCU_row(cinfo); +} + + +/* + * Initialize for an output processing pass. + */ + +METHODDEF(void) +start_output_pass (j_decompress_ptr cinfo) +{ +#ifdef BLOCK_SMOOTHING_SUPPORTED + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + /* d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; */ + + /* If multipass, check to see whether to use block smoothing on this pass */ + if (lossyd->coef_arrays != NULL) { + if (cinfo->do_block_smoothing && smoothing_ok(cinfo)) + lossyd->pub.decompress_data = decompress_smooth_data; + else + lossyd->pub.decompress_data = decompress_data; + } +#endif + cinfo->output_iMCU_row = 0; +} + + +/* + * Decompress and return some data in the single-pass case. + * Always attempts to emit one fully interleaved MCU row ("iMCU" row). + * Input and output must run in lockstep since we have only a one-MCU buffer. + * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED. + * + * NB: output_buf contains a plane for each component in image, + * which we index according to the component's SOF position. + */ + +METHODDEF(int) +decompress_onepass (j_decompress_ptr cinfo, JSAMPIMAGE output_buf) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + int blkn, ci, xindex, yindex, yoffset, useful_width; + JSAMPARRAY output_ptr; + JDIMENSION start_col, output_col; + jpeg_component_info *compptr; + inverse_DCT_method_ptr inverse_DCT; + + /* Loop to process as much as one whole iMCU row */ + for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; + yoffset++) { + for (MCU_col_num = coef->MCU_ctr; MCU_col_num <= last_MCU_col; + MCU_col_num++) { + /* Try to fetch an MCU. Entropy decoder expects buffer to be zeroed. */ + jzero_far((void FAR *) coef->MCU_buffer[0], + (size_t) (cinfo->data_units_in_MCU * SIZEOF(JBLOCK))); + if (! (*lossyd->entropy_decode_mcu) (cinfo, coef->MCU_buffer)) { + /* Suspension forced; update state counters and exit */ + coef->MCU_vert_offset = yoffset; + coef->MCU_ctr = MCU_col_num; + return JPEG_SUSPENDED; + } + /* Determine where data should go in output_buf and do the IDCT thing. + * We skip dummy blocks at the right and bottom edges (but blkn gets + * incremented past them!). Note the inner loop relies on having + * allocated the MCU_buffer[] blocks sequentially. + */ + blkn = 0; /* index of current DCT block within MCU */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + /* Don't bother to IDCT an uninteresting component. */ + if (! compptr->component_needed) { + blkn += compptr->MCU_data_units; + continue; + } + inverse_DCT = lossyd->inverse_DCT[compptr->component_index]; + useful_width = (MCU_col_num < last_MCU_col) ? compptr->MCU_width + : compptr->last_col_width; + output_ptr = output_buf[compptr->component_index] + + yoffset * compptr->codec_data_unit; + start_col = MCU_col_num * compptr->MCU_sample_width; + for (yindex = 0; yindex < compptr->MCU_height; yindex++) { + if (cinfo->input_iMCU_row < last_iMCU_row || + yoffset+yindex < compptr->last_row_height) { + output_col = start_col; + for (xindex = 0; xindex < useful_width; xindex++) { + (*inverse_DCT) (cinfo, compptr, + (JCOEFPTR) coef->MCU_buffer[blkn+xindex], + output_ptr, output_col); + output_col += compptr->codec_data_unit; + } + } + blkn += compptr->MCU_width; + output_ptr += compptr->codec_data_unit; + } + } + } + /* Completed an MCU row, but perhaps not an iMCU row */ + coef->MCU_ctr = 0; + } + /* Completed the iMCU row, advance counters for next one */ + cinfo->output_iMCU_row++; + if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) { + start_iMCU_row(cinfo); + return JPEG_ROW_COMPLETED; + } + /* Completed the scan */ + (*cinfo->inputctl->finish_input_pass) (cinfo); + return JPEG_SCAN_COMPLETED; +} + + +/* + * Dummy consume-input routine for single-pass operation. + */ + +METHODDEF(int) +dummy_consume_data (j_decompress_ptr cinfo) +{ + (void)cinfo; + return JPEG_SUSPENDED; /* Always indicate nothing was done */ +} + + +#ifdef D_MULTISCAN_FILES_SUPPORTED + +/* + * Consume input data and store it in the full-image coefficient buffer. + * We read as much as one fully interleaved MCU row ("iMCU" row) per call, + * ie, v_samp_factor block rows for each component in the scan. + * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED. + */ + +METHODDEF(int) +consume_data (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + int blkn, ci, xindex, yindex, yoffset; + JDIMENSION start_col; + JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN]; + JBLOCKROW buffer_ptr; + jpeg_component_info *compptr; + + /* Align the virtual buffers for the components used in this scan. */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + buffer[ci] = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index], + cinfo->input_iMCU_row * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, TRUE); + /* Note: entropy decoder expects buffer to be zeroed, + * but this is handled automatically by the memory manager + * because we requested a pre-zeroed array. + */ + } + + /* Loop to process one whole iMCU row */ + for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row; + yoffset++) { + for (MCU_col_num = coef->MCU_ctr; MCU_col_num < cinfo->MCUs_per_row; + MCU_col_num++) { + /* Construct list of pointers to DCT blocks belonging to this MCU */ + blkn = 0; /* index of current DCT block within MCU */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + start_col = MCU_col_num * compptr->MCU_width; + for (yindex = 0; yindex < compptr->MCU_height; yindex++) { + buffer_ptr = buffer[ci][yindex+yoffset] + start_col; + for (xindex = 0; xindex < compptr->MCU_width; xindex++) { + coef->MCU_buffer[blkn++] = buffer_ptr++; + } + } + } + /* Try to fetch the MCU. */ + if (! (*lossyd->entropy_decode_mcu) (cinfo, coef->MCU_buffer)) { + /* Suspension forced; update state counters and exit */ + coef->MCU_vert_offset = yoffset; + coef->MCU_ctr = MCU_col_num; + return JPEG_SUSPENDED; + } + } + /* Completed an MCU row, but perhaps not an iMCU row */ + coef->MCU_ctr = 0; + } + /* Completed the iMCU row, advance counters for next one */ + if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) { + start_iMCU_row(cinfo); + return JPEG_ROW_COMPLETED; + } + /* Completed the scan */ + (*cinfo->inputctl->finish_input_pass) (cinfo); + return JPEG_SCAN_COMPLETED; +} + + +/* + * Decompress and return some data in the multi-pass case. + * Always attempts to emit one fully interleaved MCU row ("iMCU" row). + * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED. + * + * NB: output_buf contains a plane for each component in image. + */ + +METHODDEF(int) +decompress_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + JDIMENSION block_num; + int ci, block_row, block_rows; + JBLOCKARRAY buffer; + JBLOCKROW buffer_ptr; + JSAMPARRAY output_ptr; + JDIMENSION output_col; + jpeg_component_info *compptr; + inverse_DCT_method_ptr inverse_DCT; + + /* Force some input to be done if we are getting ahead of the input. */ + while (cinfo->input_scan_number < cinfo->output_scan_number || + (cinfo->input_scan_number == cinfo->output_scan_number && + cinfo->input_iMCU_row <= cinfo->output_iMCU_row)) { + if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED) + return JPEG_SUSPENDED; + } + + /* OK, output from the virtual arrays. */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Don't bother to IDCT an uninteresting component. */ + if (! compptr->component_needed) + continue; + /* Align the virtual buffer for this component. */ + buffer = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[ci], + cinfo->output_iMCU_row * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, FALSE); + /* Count non-dummy DCT block rows in this iMCU row. */ + if (cinfo->output_iMCU_row < last_iMCU_row) + block_rows = compptr->v_samp_factor; + else { + /* NB: can't use last_row_height here; it is input-side-dependent! */ + block_rows = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (block_rows == 0) block_rows = compptr->v_samp_factor; + } + inverse_DCT = lossyd->inverse_DCT[ci]; + output_ptr = output_buf[ci]; + /* Loop over all DCT blocks to be processed. */ + for (block_row = 0; block_row < block_rows; block_row++) { + buffer_ptr = buffer[block_row]; + output_col = 0; + for (block_num = 0; block_num < compptr->width_in_data_units; block_num++) { + (*inverse_DCT) (cinfo, compptr, (JCOEFPTR) buffer_ptr, + output_ptr, output_col); + buffer_ptr++; + output_col += compptr->codec_data_unit; + } + output_ptr += compptr->codec_data_unit; + } + } + + if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows) + return JPEG_ROW_COMPLETED; + return JPEG_SCAN_COMPLETED; +} + +#endif /* D_MULTISCAN_FILES_SUPPORTED */ + + +#ifdef BLOCK_SMOOTHING_SUPPORTED + +/* + * This code applies interblock smoothing as described by section K.8 + * of the JPEG standard: the first 5 AC coefficients are estimated from + * the DC values of a DCT block and its 8 neighboring blocks. + * We apply smoothing only for progressive JPEG decoding, and only if + * the coefficients it can estimate are not yet known to full precision. + */ + +/* Natural-order array positions of the first 5 zigzag-order coefficients */ +#define Q01_POS 1 +#define Q10_POS 8 +#define Q20_POS 16 +#define Q11_POS 9 +#define Q02_POS 2 + +/* + * Determine whether block smoothing is applicable and safe. + * We also latch the current states of the coef_bits[] entries for the + * AC coefficients; otherwise, if the input side of the decompressor + * advances into a new scan, we might think the coefficients are known + * more accurately than they really are. + */ + +LOCAL(boolean) +smoothing_ok (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; + boolean smoothing_useful = FALSE; + int ci, coefi; + jpeg_component_info *compptr; + JQUANT_TBL * qtable; + int * coef_bits; + int * coef_bits_latch; + + if (! cinfo->process == JPROC_PROGRESSIVE || cinfo->coef_bits == NULL) + return FALSE; + + /* Allocate latch area if not already done */ + if (coef->coef_bits_latch == NULL) + coef->coef_bits_latch = (int *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + cinfo->num_components * + (SAVED_COEFS * SIZEOF(int))); + coef_bits_latch = coef->coef_bits_latch; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* All components' quantization values must already be latched. */ + if ((qtable = compptr->quant_table) == NULL) + return FALSE; + /* Verify DC & first 5 AC quantizers are nonzero to avoid zero-divide. */ + if (qtable->quantval[0] == 0 || + qtable->quantval[Q01_POS] == 0 || + qtable->quantval[Q10_POS] == 0 || + qtable->quantval[Q20_POS] == 0 || + qtable->quantval[Q11_POS] == 0 || + qtable->quantval[Q02_POS] == 0) + return FALSE; + /* DC values must be at least partly known for all components. */ + coef_bits = cinfo->coef_bits[ci]; + if (coef_bits[0] < 0) + return FALSE; + /* Block smoothing is helpful if some AC coefficients remain inaccurate. */ + for (coefi = 1; coefi <= 5; coefi++) { + coef_bits_latch[coefi] = coef_bits[coefi]; + if (coef_bits[coefi] != 0) + smoothing_useful = TRUE; + } + coef_bits_latch += SAVED_COEFS; + } + + return smoothing_useful; +} + + +/* + * Variant of decompress_data for use when doing block smoothing. + */ + +METHODDEF(int) +decompress_smooth_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef = (d_coef_ptr) lossyd->coef_private; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + JDIMENSION block_num, last_block_column; + int ci, block_row, block_rows, access_rows; + JBLOCKARRAY buffer; + JBLOCKROW buffer_ptr, prev_block_row, next_block_row; + JSAMPARRAY output_ptr; + JDIMENSION output_col; + jpeg_component_info *compptr; + inverse_DCT_method_ptr inverse_DCT; + boolean first_row, last_row; + JBLOCK workspace; + int *coef_bits; + JQUANT_TBL *quanttbl; + INT32 Q00,Q01,Q02,Q10,Q11,Q20, num; + int DC1,DC2,DC3,DC4,DC5,DC6,DC7,DC8,DC9; + int Al, pred; + + /* Force some input to be done if we are getting ahead of the input. */ + while (cinfo->input_scan_number <= cinfo->output_scan_number && + ! cinfo->inputctl->eoi_reached) { + if (cinfo->input_scan_number == cinfo->output_scan_number) { + /* If input is working on current scan, we ordinarily want it to + * have completed the current row. But if input scan is DC, + * we want it to keep one row ahead so that next block row's DC + * values are up to date. + */ + JDIMENSION delta = (cinfo->Ss == 0) ? 1 : 0; + if (cinfo->input_iMCU_row > cinfo->output_iMCU_row+delta) + break; + } + if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED) + return JPEG_SUSPENDED; + } + + /* OK, output from the virtual arrays. */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Don't bother to IDCT an uninteresting component. */ + if (! compptr->component_needed) + continue; + /* Count non-dummy DCT block rows in this iMCU row. */ + if (cinfo->output_iMCU_row < last_iMCU_row) { + block_rows = compptr->v_samp_factor; + access_rows = block_rows * 2; /* this and next iMCU row */ + last_row = FALSE; + } else { + /* NB: can't use last_row_height here; it is input-side-dependent! */ + block_rows = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (block_rows == 0) block_rows = compptr->v_samp_factor; + access_rows = block_rows; /* this iMCU row only */ + last_row = TRUE; + } + /* Align the virtual buffer for this component. */ + if (cinfo->output_iMCU_row > 0) { + access_rows += compptr->v_samp_factor; /* prior iMCU row too */ + buffer = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[ci], + (cinfo->output_iMCU_row - 1) * compptr->v_samp_factor, + (JDIMENSION) access_rows, FALSE); + buffer += compptr->v_samp_factor; /* point to current iMCU row */ + first_row = FALSE; + } else { + buffer = (*cinfo->mem->access_virt_barray) + ((j_common_ptr) cinfo, coef->whole_image[ci], + (JDIMENSION) 0, (JDIMENSION) access_rows, FALSE); + first_row = TRUE; + } + /* Fetch component-dependent info */ + coef_bits = coef->coef_bits_latch + (ci * SAVED_COEFS); + quanttbl = compptr->quant_table; + Q00 = quanttbl->quantval[0]; + Q01 = quanttbl->quantval[Q01_POS]; + Q10 = quanttbl->quantval[Q10_POS]; + Q20 = quanttbl->quantval[Q20_POS]; + Q11 = quanttbl->quantval[Q11_POS]; + Q02 = quanttbl->quantval[Q02_POS]; + inverse_DCT = lossyd->inverse_DCT[ci]; + output_ptr = output_buf[ci]; + /* Loop over all DCT blocks to be processed. */ + for (block_row = 0; block_row < block_rows; block_row++) { + buffer_ptr = buffer[block_row]; + if (first_row && block_row == 0) + prev_block_row = buffer_ptr; + else + prev_block_row = buffer[block_row-1]; + if (last_row && block_row == block_rows-1) + next_block_row = buffer_ptr; + else + next_block_row = buffer[block_row+1]; + /* We fetch the surrounding DC values using a sliding-register approach. + * Initialize all nine here so as to do the right thing on narrow pics. + */ + DC1 = DC2 = DC3 = (int) prev_block_row[0][0]; + DC4 = DC5 = DC6 = (int) buffer_ptr[0][0]; + DC7 = DC8 = DC9 = (int) next_block_row[0][0]; + output_col = 0; + last_block_column = compptr->width_in_data_units - 1; + for (block_num = 0; block_num <= last_block_column; block_num++) { + /* Fetch current DCT block into workspace so we can modify it. */ + jcopy_block_row(buffer_ptr, (JBLOCKROW) workspace, (JDIMENSION) 1); + /* Update DC values */ + if (block_num < last_block_column) { + DC3 = (int) prev_block_row[1][0]; + DC6 = (int) buffer_ptr[1][0]; + DC9 = (int) next_block_row[1][0]; + } + /* Compute coefficient estimates per K.8. + * An estimate is applied only if coefficient is still zero, + * and is not known to be fully accurate. + */ + /* AC01 */ + if ((Al=coef_bits[1]) != 0 && workspace[1] == 0) { + num = 36 * Q00 * (DC4 - DC6); + if (num >= 0) { + pred = (int) (((Q01<<7) + num) / (Q01<<8)); + if (Al > 0 && pred >= (1< 0 && pred >= (1<= 0) { + pred = (int) (((Q10<<7) + num) / (Q10<<8)); + if (Al > 0 && pred >= (1< 0 && pred >= (1<= 0) { + pred = (int) (((Q20<<7) + num) / (Q20<<8)); + if (Al > 0 && pred >= (1< 0 && pred >= (1<= 0) { + pred = (int) (((Q11<<7) + num) / (Q11<<8)); + if (Al > 0 && pred >= (1< 0 && pred >= (1<= 0) { + pred = (int) (((Q02<<7) + num) / (Q02<<8)); + if (Al > 0 && pred >= (1< 0 && pred >= (1<codec_data_unit; + } + output_ptr += compptr->codec_data_unit; + } + } + + if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows) + return JPEG_ROW_COMPLETED; + return JPEG_SCAN_COMPLETED; +} + +#endif /* BLOCK_SMOOTHING_SUPPORTED */ + + +/* + * Initialize coefficient buffer controller. + */ + +GLOBAL(void) +jinit_d_coef_controller (j_decompress_ptr cinfo, boolean need_full_buffer) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + d_coef_ptr coef; + + coef = (d_coef_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(d_coef_controller)); + lossyd->coef_private = (void *) coef; + lossyd->coef_start_input_pass = start_input_pass; + lossyd->coef_start_output_pass = start_output_pass; +#ifdef BLOCK_SMOOTHING_SUPPORTED + coef->coef_bits_latch = NULL; +#endif + + /* Create the coefficient buffer. */ + if (need_full_buffer) { +#ifdef D_MULTISCAN_FILES_SUPPORTED + /* Allocate a full-image virtual array for each component, */ + /* padded to a multiple of samp_factor DCT blocks in each direction. */ + /* Note we ask for a pre-zeroed array. */ + int ci, access_rows; + jpeg_component_info *compptr; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + access_rows = compptr->v_samp_factor; +#ifdef BLOCK_SMOOTHING_SUPPORTED + /* If block smoothing could be used, need a bigger window */ + if (cinfo->process == JPROC_PROGRESSIVE) + access_rows *= 3; +#endif + coef->whole_image[ci] = (*cinfo->mem->request_virt_barray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, TRUE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) jround_up((long) compptr->height_in_data_units, + (long) compptr->v_samp_factor), + (JDIMENSION) access_rows); + } + lossyd->pub.consume_data = consume_data; + lossyd->pub.decompress_data = decompress_data; + lossyd->coef_arrays = coef->whole_image; /* link to virtual arrays */ +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + /* We only need a single-MCU buffer. */ + JBLOCKROW buffer; + int i; + + buffer = (JBLOCKROW) + (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, + D_MAX_DATA_UNITS_IN_MCU * SIZEOF(JBLOCK)); + for (i = 0; i < D_MAX_DATA_UNITS_IN_MCU; i++) { + coef->MCU_buffer[i] = buffer + i; + } + lossyd->pub.consume_data = dummy_consume_data; + lossyd->pub.decompress_data = decompress_onepass; + lossyd->coef_arrays = NULL; /* flag for no virtual arrays */ + } +} diff --git a/src/gdcmjpeg/jdcolor.c b/src/gdcmjpeg/jdcolor.c new file mode 100644 index 00000000..7b0aa3d7 --- /dev/null +++ b/src/gdcmjpeg/jdcolor.c @@ -0,0 +1,414 @@ +/* + * jdcolor.c + * + * Copyright (C) 1991-1997, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains output colorspace conversion routines. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Private subobject */ + +typedef struct { + struct jpeg_color_deconverter pub; /* public fields */ + + /* Private state for YCC->RGB conversion */ + int * Cr_r_tab; /* => table for Cr to R conversion */ + int * Cb_b_tab; /* => table for Cb to B conversion */ + INT32 * Cr_g_tab; /* => table for Cr to G conversion */ + INT32 * Cb_g_tab; /* => table for Cb to G conversion */ +} my_color_deconverter; + +typedef my_color_deconverter * my_cconvert_ptr; + + +/**************** YCbCr -> RGB conversion: most common case **************/ + +/* + * YCbCr is defined per CCIR 601-1, except that Cb and Cr are + * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. + * The conversion equations to be implemented are therefore + * R = Y + 1.40200 * Cr + * G = Y - 0.34414 * Cb - 0.71414 * Cr + * B = Y + 1.77200 * Cb + * where Cb and Cr represent the incoming values less CENTERJSAMPLE. + * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.) + * + * To avoid floating-point arithmetic, we represent the fractional constants + * as integers scaled up by 2^16 (about 4 digits precision); we have to divide + * the products by 2^16, with appropriate rounding, to get the correct answer. + * Notice that Y, being an integral input, does not contribute any fraction + * so it need not participate in the rounding. + * + * For even more speed, we avoid doing any multiplications in the inner loop + * by precalculating the constants times Cb and Cr for all possible values. + * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table); + * for 12-bit samples it is still acceptable. It's not very reasonable for + * 16-bit samples, but if you want lossless storage you shouldn't be changing + * colorspace anyway. + * The Cr=>R and Cb=>B values can be rounded to integers in advance; the + * values for the G calculation are left scaled up, since we must add them + * together before rounding. + */ + +#define SCALEBITS 16 /* speediest right-shift on some machines */ +#define ONE_HALF ((INT32) 1 << (SCALEBITS-1)) +#define FIX(x) ((INT32) ((x) * (1L<RGB colorspace conversion. + */ + +LOCAL(void) +build_ycc_rgb_table (j_decompress_ptr cinfo) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + int i; + INT32 x; +#if BITS_IN_JSAMPLE == 16 + /* no need for temporaries */ +#else + SHIFT_TEMPS +#endif + + cconvert->Cr_r_tab = (int *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(int)); + cconvert->Cb_b_tab = (int *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(int)); + cconvert->Cr_g_tab = (INT32 *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(INT32)); + cconvert->Cb_g_tab = (INT32 *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(INT32)); + + for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) { + /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */ + /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */ + +#if BITS_IN_JSAMPLE == 16 + /* Bug fix 2001-11-06 by Eichelberg: The integer routines below + produce an overflow when used with MAXJSAMPLE == 65535. + Use floating point calculation instead. */ + + /* Cr=>R value is nearest int to 1.40200 * x */ + cconvert->Cr_r_tab[i] = (int)(1.40200 * (double)x + 0.5); + /* Cb=>B value is nearest int to 1.77200 * x */ + cconvert->Cb_b_tab[i] = (int)(1.77200 * (double)x + 0.5); +#else + /* Cr=>R value is nearest int to 1.40200 * x */ + cconvert->Cr_r_tab[i] = (int) + RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS); + /* Cb=>B value is nearest int to 1.77200 * x */ + cconvert->Cb_b_tab[i] = (int) + RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS); +#endif + + /* Cr=>G value is scaled-up -0.71414 * x */ + cconvert->Cr_g_tab[i] = (- FIX(0.71414)) * x; + /* Cb=>G value is scaled-up -0.34414 * x */ + /* We also add in ONE_HALF so that need not do it in inner loop */ + cconvert->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF; + } +} + + +/* + * Convert some rows of samples to the output colorspace. + * + * Note that we change from noninterleaved, one-plane-per-component format + * to interleaved-pixel format. The output buffer is therefore three times + * as wide as the input buffer. + * A starting row offset is provided only for the input buffer. The caller + * can easily adjust the passed output_buf value to accommodate any row + * offset required on that side. + */ + +METHODDEF(void) +ycc_rgb_convert (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION input_row, + JSAMPARRAY output_buf, int num_rows) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + register int y, cb, cr; + register JSAMPROW outptr; + register JSAMPROW inptr0, inptr1, inptr2; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->output_width; + /* copy these pointers into registers if possible */ + register JSAMPLE * range_limit = cinfo->sample_range_limit; + register int * Crrtab = cconvert->Cr_r_tab; + register int * Cbbtab = cconvert->Cb_b_tab; + register INT32 * Crgtab = cconvert->Cr_g_tab; + register INT32 * Cbgtab = cconvert->Cb_g_tab; + SHIFT_TEMPS + + while (--num_rows >= 0) { + inptr0 = input_buf[0][input_row]; + inptr1 = input_buf[1][input_row]; + inptr2 = input_buf[2][input_row]; + input_row++; + outptr = *output_buf++; + for (col = 0; col < num_cols; col++) { + y = GETJSAMPLE(inptr0[col]); + cb = GETJSAMPLE(inptr1[col]); + cr = GETJSAMPLE(inptr2[col]); + /* Range-limiting is essential due to noise introduced by DCT losses. */ + outptr[RGB_RED] = range_limit[y + Crrtab[cr]]; + outptr[RGB_GREEN] = range_limit[y + + ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], + SCALEBITS))]; + outptr[RGB_BLUE] = range_limit[y + Cbbtab[cb]]; + outptr += RGB_PIXELSIZE; + } + } +} + + +/**************** Cases other than YCbCr -> RGB **************/ + + +/* + * Color conversion for no colorspace change: just copy the data, + * converting from separate-planes to interleaved representation. + */ + +METHODDEF(void) +null_convert (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION input_row, + JSAMPARRAY output_buf, int num_rows) +{ + register JSAMPROW inptr, outptr; + register JDIMENSION count; + register int num_components = cinfo->num_components; + JDIMENSION num_cols = cinfo->output_width; + int ci; + + while (--num_rows >= 0) { + for (ci = 0; ci < num_components; ci++) { + inptr = input_buf[ci][input_row]; + outptr = output_buf[0] + ci; + for (count = num_cols; count > 0; count--) { + *outptr = *inptr++; /* needn't bother with GETJSAMPLE() here */ + outptr += num_components; + } + } + input_row++; + output_buf++; + } +} + + +/* + * Color conversion for grayscale: just copy the data. + * This also works for YCbCr -> grayscale conversion, in which + * we just copy the Y (luminance) component and ignore chrominance. + */ + +METHODDEF(void) +grayscale_convert (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION input_row, + JSAMPARRAY output_buf, int num_rows) +{ + jcopy_sample_rows(input_buf[0], (int) input_row, output_buf, 0, + num_rows, cinfo->output_width); +} + + +/* + * Convert grayscale to RGB: just duplicate the graylevel three times. + * This is provided to support applications that don't want to cope + * with grayscale as a separate case. + */ + +METHODDEF(void) +gray_rgb_convert (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION input_row, + JSAMPARRAY output_buf, int num_rows) +{ + register JSAMPROW inptr, outptr; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->output_width; + + while (--num_rows >= 0) { + inptr = input_buf[0][input_row++]; + outptr = *output_buf++; + for (col = 0; col < num_cols; col++) { + /* We can dispense with GETJSAMPLE() here */ + outptr[RGB_RED] = outptr[RGB_GREEN] = outptr[RGB_BLUE] = inptr[col]; + outptr += RGB_PIXELSIZE; + } + } +} + + +/* + * Adobe-style YCCK->CMYK conversion. + * We convert YCbCr to R=1-C, G=1-M, and B=1-Y using the same + * conversion as above, while passing K (black) unchanged. + * We assume build_ycc_rgb_table has been called. + */ + +METHODDEF(void) +ycck_cmyk_convert (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION input_row, + JSAMPARRAY output_buf, int num_rows) +{ + my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; + register int y, cb, cr; + register JSAMPROW outptr; + register JSAMPROW inptr0, inptr1, inptr2, inptr3; + register JDIMENSION col; + JDIMENSION num_cols = cinfo->output_width; + /* copy these pointers into registers if possible */ + register JSAMPLE * range_limit = cinfo->sample_range_limit; + register int * Crrtab = cconvert->Cr_r_tab; + register int * Cbbtab = cconvert->Cb_b_tab; + register INT32 * Crgtab = cconvert->Cr_g_tab; + register INT32 * Cbgtab = cconvert->Cb_g_tab; + SHIFT_TEMPS + + while (--num_rows >= 0) { + inptr0 = input_buf[0][input_row]; + inptr1 = input_buf[1][input_row]; + inptr2 = input_buf[2][input_row]; + inptr3 = input_buf[3][input_row]; + input_row++; + outptr = *output_buf++; + for (col = 0; col < num_cols; col++) { + y = GETJSAMPLE(inptr0[col]); + cb = GETJSAMPLE(inptr1[col]); + cr = GETJSAMPLE(inptr2[col]); + /* Range-limiting is essential due to noise introduced by DCT losses. */ + outptr[0] = range_limit[MAXJSAMPLE - (y + Crrtab[cr])]; /* red */ + outptr[1] = range_limit[MAXJSAMPLE - (y + /* green */ + ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], + SCALEBITS)))]; + outptr[2] = range_limit[MAXJSAMPLE - (y + Cbbtab[cb])]; /* blue */ + /* K passes through unchanged */ + outptr[3] = inptr3[col]; /* don't need GETJSAMPLE here */ + outptr += 4; + } + } +} + + +/* + * Empty method for start_pass. + */ + +METHODDEF(void) +start_pass_dcolor (j_decompress_ptr cinfo) +{ + (void)cinfo; + /* no work needed */ +} + + +/* + * Module initialization routine for output colorspace conversion. + */ + +GLOBAL(void) +jinit_color_deconverter (j_decompress_ptr cinfo) +{ + my_cconvert_ptr cconvert; + int ci; + + cconvert = (my_cconvert_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_color_deconverter)); + cinfo->cconvert = (struct jpeg_color_deconverter *) cconvert; + cconvert->pub.start_pass = start_pass_dcolor; + + /* Make sure num_components agrees with jpeg_color_space */ + switch (cinfo->jpeg_color_space) { + case JCS_GRAYSCALE: + if (cinfo->num_components != 1) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + break; + + case JCS_RGB: + case JCS_YCbCr: + if (cinfo->num_components != 3) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + break; + + case JCS_CMYK: + case JCS_YCCK: + if (cinfo->num_components != 4) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + break; + + default: /* JCS_UNKNOWN can be anything */ + if (cinfo->num_components < 1) + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); + break; + } + + /* Set out_color_components and conversion method based on requested space. + * Also clear the component_needed flags for any unused components, + * so that earlier pipeline stages can avoid useless computation. + */ + + switch (cinfo->out_color_space) { + case JCS_GRAYSCALE: + cinfo->out_color_components = 1; + if (cinfo->jpeg_color_space == JCS_GRAYSCALE || + cinfo->jpeg_color_space == JCS_YCbCr) { + cconvert->pub.color_convert = grayscale_convert; + /* For color->grayscale conversion, only the Y (0) component is needed */ + for (ci = 1; ci < cinfo->num_components; ci++) + cinfo->comp_info[ci].component_needed = FALSE; + } else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + case JCS_RGB: + cinfo->out_color_components = RGB_PIXELSIZE; + if (cinfo->jpeg_color_space == JCS_YCbCr) { + cconvert->pub.color_convert = ycc_rgb_convert; + build_ycc_rgb_table(cinfo); + } else if (cinfo->jpeg_color_space == JCS_GRAYSCALE) { + cconvert->pub.color_convert = gray_rgb_convert; + } else if (cinfo->jpeg_color_space == JCS_RGB && RGB_PIXELSIZE == 3) { + cconvert->pub.color_convert = null_convert; + } else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + case JCS_CMYK: + cinfo->out_color_components = 4; + if (cinfo->jpeg_color_space == JCS_YCCK) { + cconvert->pub.color_convert = ycck_cmyk_convert; + build_ycc_rgb_table(cinfo); + } else if (cinfo->jpeg_color_space == JCS_CMYK) { + cconvert->pub.color_convert = null_convert; + } else + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + + default: + /* Permit null conversion to same output space */ + if (cinfo->out_color_space == cinfo->jpeg_color_space) { + cinfo->out_color_components = cinfo->num_components; + cconvert->pub.color_convert = null_convert; + } else /* unsupported non-null conversion */ + ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); + break; + } + + if (cinfo->quantize_colors) + cinfo->output_components = 1; /* single colormapped output component */ + else + cinfo->output_components = cinfo->out_color_components; +} diff --git a/src/gdcmjpeg/jdct.h b/src/gdcmjpeg/jdct.h new file mode 100644 index 00000000..ffdd5e50 --- /dev/null +++ b/src/gdcmjpeg/jdct.h @@ -0,0 +1,176 @@ +/* + * jdct.h + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This include file contains common declarations for the forward and + * inverse DCT modules. These declarations are private to the DCT managers + * (jcdctmgr.c, jddctmgr.c) and the individual DCT algorithms. + * The individual DCT algorithms are kept in separate files to ease + * machine-dependent tuning (e.g., assembly coding). + */ + + +/* + * A forward DCT routine is given a pointer to a work area of type DCTELEM[]; + * the DCT is to be performed in-place in that buffer. Type DCTELEM is int + * for 8-bit samples, INT32 for 12-bit samples. (NOTE: Floating-point DCT + * implementations use an array of type FAST_FLOAT, instead.) + * The DCT inputs are expected to be signed (range +-CENTERJSAMPLE). + * The DCT outputs are returned scaled up by a factor of 8; they therefore + * have a range of +-8K for 8-bit data, +-128K for 12-bit data. This + * convention improves accuracy in integer implementations and saves some + * work in floating-point ones. + * Quantization of the output coefficients is done by jcdctmgr.c. + */ + +#if BITS_IN_JSAMPLE == 8 +typedef int DCTELEM; /* 16 or 32 bits is fine */ +#else +typedef INT32 DCTELEM; /* must have 32 bits */ +#endif + +typedef JMETHOD(void, forward_DCT_method_ptr, (DCTELEM * data)); +typedef JMETHOD(void, float_DCT_method_ptr, (FAST_FLOAT * data)); + + +/* + * An inverse DCT routine is given a pointer to the input JBLOCK and a pointer + * to an output sample array. The routine must dequantize the input data as + * well as perform the IDCT; for dequantization, it uses the multiplier table + * pointed to by compptr->dct_table. The output data is to be placed into the + * sample array starting at a specified column. (Any row offset needed will + * be applied to the array pointer before it is passed to the IDCT code.) + * Note that the number of samples emitted by the IDCT routine is + * DCT_scaled_size * DCT_scaled_size. + */ + +/* typedef inverse_DCT_method_ptr is declared in jpegint.h */ + +/* + * Each IDCT routine has its own ideas about the best dct_table element type. + */ + +typedef MULTIPLIER ISLOW_MULT_TYPE; /* short or int, whichever is faster */ +#if BITS_IN_JSAMPLE == 8 +typedef MULTIPLIER IFAST_MULT_TYPE; /* 16 bits is OK, use short if faster */ +#define IFAST_SCALE_BITS 2 /* fractional bits in scale factors */ +#else +typedef INT32 IFAST_MULT_TYPE; /* need 32 bits for scaled quantizers */ +#define IFAST_SCALE_BITS 13 /* fractional bits in scale factors */ +#endif +typedef FAST_FLOAT FLOAT_MULT_TYPE; /* preferred floating type */ + + +/* + * Each IDCT routine is responsible for range-limiting its results and + * converting them to unsigned form (0..MAXJSAMPLE). The raw outputs could + * be quite far out of range if the input data is corrupt, so a bulletproof + * range-limiting step is required. We use a mask-and-table-lookup method + * to do the combined operations quickly. See the comments with + * prepare_range_limit_table (in jdmaster.c) for more info. + */ + +#define IDCT_range_limit(cinfo) ((cinfo)->sample_range_limit + CENTERJSAMPLE) + +#define RANGE_MASK (MAXJSAMPLE * 4 + 3) /* 2 bits wider than legal samples */ + + +/* Short forms of external names for systems with brain-damaged linkers. */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jpeg_fdct_islow jFDislow +#define jpeg_fdct_ifast jFDifast +#define jpeg_fdct_float jFDfloat +#define jpeg_idct_islow jRDislow +#define jpeg_idct_ifast jRDifast +#define jpeg_idct_float jRDfloat +#define jpeg_idct_4x4 jRD4x4 +#define jpeg_idct_2x2 jRD2x2 +#define jpeg_idct_1x1 jRD1x1 +#endif /* NEED_SHORT_EXTERNAL_NAMES */ + +/* Extern declarations for the forward and inverse DCT routines. */ + +EXTERN(void) jpeg_fdct_islow JPP((DCTELEM * data)); +EXTERN(void) jpeg_fdct_ifast JPP((DCTELEM * data)); +EXTERN(void) jpeg_fdct_float JPP((FAST_FLOAT * data)); + +EXTERN(void) jpeg_idct_islow + JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); +EXTERN(void) jpeg_idct_ifast + JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); +EXTERN(void) jpeg_idct_float + JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); +EXTERN(void) jpeg_idct_4x4 + JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); +EXTERN(void) jpeg_idct_2x2 + JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); +EXTERN(void) jpeg_idct_1x1 + JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col)); + + +/* + * Macros for handling fixed-point arithmetic; these are used by many + * but not all of the DCT/IDCT modules. + * + * All values are expected to be of type INT32. + * Fractional constants are scaled left by CONST_BITS bits. + * CONST_BITS is defined within each module using these macros, + * and may differ from one module to the next. + */ + +#define ONE ((INT32) 1) +#define CONST_SCALE (ONE << CONST_BITS) + +/* Convert a positive real constant to an integer scaled by CONST_SCALE. + * Caution: some C compilers fail to reduce "FIX(constant)" at compile time, + * thus causing a lot of useless floating-point operations at run time. + */ + +#define FIX(x) ((INT32) ((x) * CONST_SCALE + 0.5)) + +/* Descale and correctly round an INT32 value that's scaled by N bits. + * We assume RIGHT_SHIFT rounds towards minus infinity, so adding + * the fudge factor is correct for either sign of X. + */ + +#define DESCALE(x,n) RIGHT_SHIFT((x) + (ONE << ((n)-1)), n) + +/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result. + * This macro is used only when the two inputs will actually be no more than + * 16 bits wide, so that a 16x16->32 bit multiply can be used instead of a + * full 32x32 multiply. This provides a useful speedup on many machines. + * Unfortunately there is no way to specify a 16x16->32 multiply portably + * in C, but some C compilers will do the right thing if you provide the + * correct combination of casts. + */ + +#ifdef SHORTxSHORT_32 /* may work if 'int' is 32 bits */ +#define MULTIPLY16C16(var,const) (((INT16) (var)) * ((INT16) (const))) +#endif +#ifdef SHORTxLCONST_32 /* known to work with Microsoft C 6.0 */ +#define MULTIPLY16C16(var,const) (((INT16) (var)) * ((INT32) (const))) +#endif + +#ifndef MULTIPLY16C16 /* default definition */ +#define MULTIPLY16C16(var,const) ((var) * (const)) +#endif + +/* Same except both inputs are variables. */ + +#ifdef SHORTxSHORT_32 /* may work if 'int' is 32 bits */ +#define MULTIPLY16V16(var1,var2) (((INT16) (var1)) * ((INT16) (var2))) +#endif + +#ifndef MULTIPLY16V16 /* default definition */ +#define MULTIPLY16V16(var1,var2) ((var1) * (var2)) +#endif diff --git a/src/gdcmjpeg/jddctmgr.c b/src/gdcmjpeg/jddctmgr.c new file mode 100644 index 00000000..6f6c4442 --- /dev/null +++ b/src/gdcmjpeg/jddctmgr.c @@ -0,0 +1,270 @@ +/* + * jddctmgr.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the inverse-DCT management logic. + * This code selects a particular IDCT implementation to be used, + * and it performs related housekeeping chores. No code in this file + * is executed per IDCT step, only during output pass setup. + * + * Note that the IDCT routines are responsible for performing coefficient + * dequantization as well as the IDCT proper. This module sets up the + * dequantization multiplier table needed by the IDCT routine. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy subsystem */ +#include "jdct.h" /* Private declarations for DCT subsystem */ + + +/* + * The decompressor input side (jdinput.c) saves away the appropriate + * quantization table for each component at the start of the first scan + * involving that component. (This is necessary in order to correctly + * decode files that reuse Q-table slots.) + * When we are ready to make an output pass, the saved Q-table is converted + * to a multiplier table that will actually be used by the IDCT routine. + * The multiplier table contents are IDCT-method-dependent. To support + * application changes in IDCT method between scans, we can remake the + * multiplier tables if necessary. + * In buffered-image mode, the first output pass may occur before any data + * has been seen for some components, and thus before their Q-tables have + * been saved away. To handle this case, multiplier tables are preset + * to zeroes; the result of the IDCT will be a neutral gray level. + */ + + +/* Private subobject for this module */ + +typedef struct { + /* This array contains the IDCT method code that each multiplier table + * is currently set up for, or -1 if it's not yet set up. + * The actual multiplier tables are pointed to by dct_table in the + * per-component comp_info structures. + */ + int cur_method[MAX_COMPONENTS]; +} idct_controller; + +typedef idct_controller * idct_ptr; + + +/* Allocated multiplier tables: big enough for any supported variant */ + +typedef union { + ISLOW_MULT_TYPE islow_array[DCTSIZE2]; +#ifdef DCT_IFAST_SUPPORTED + IFAST_MULT_TYPE ifast_array[DCTSIZE2]; +#endif +#ifdef DCT_FLOAT_SUPPORTED + FLOAT_MULT_TYPE float_array[DCTSIZE2]; +#endif +} multiplier_table; + + +/* The current scaled-IDCT routines require ISLOW-style multiplier tables, + * so be sure to compile that code if either ISLOW or SCALING is requested. + */ +#ifdef DCT_ISLOW_SUPPORTED +#define PROVIDE_ISLOW_TABLES +#else +#ifdef IDCT_SCALING_SUPPORTED +#define PROVIDE_ISLOW_TABLES +#endif +#endif + + +/* + * Prepare for an output pass. + * Here we select the proper IDCT routine for each component and build + * a matching multiplier table. + */ + +METHODDEF(void) +start_pass (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + idct_ptr idct = (idct_ptr) lossyd->idct_private; + int ci, i; + jpeg_component_info *compptr; + int method = 0; + inverse_DCT_method_ptr method_ptr = NULL; + JQUANT_TBL * qtbl; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Select the proper IDCT routine for this component's scaling */ + switch (compptr->codec_data_unit) { +#ifdef IDCT_SCALING_SUPPORTED + case 1: + method_ptr = jpeg_idct_1x1; + method = JDCT_ISLOW; /* jidctred uses islow-style table */ + break; + case 2: + method_ptr = jpeg_idct_2x2; + method = JDCT_ISLOW; /* jidctred uses islow-style table */ + break; + case 4: + method_ptr = jpeg_idct_4x4; + method = JDCT_ISLOW; /* jidctred uses islow-style table */ + break; +#endif + case DCTSIZE: + switch (cinfo->dct_method) { +#ifdef DCT_ISLOW_SUPPORTED + case JDCT_ISLOW: + method_ptr = jpeg_idct_islow; + method = JDCT_ISLOW; + break; +#endif +#ifdef DCT_IFAST_SUPPORTED + case JDCT_IFAST: + method_ptr = jpeg_idct_ifast; + method = JDCT_IFAST; + break; +#endif +#ifdef DCT_FLOAT_SUPPORTED + case JDCT_FLOAT: + method_ptr = jpeg_idct_float; + method = JDCT_FLOAT; + break; +#endif + default: + ERREXIT(cinfo, JERR_NOT_COMPILED); + break; + } + break; + default: + ERREXIT1(cinfo, JERR_BAD_DCTSIZE, compptr->codec_data_unit); + break; + } + lossyd->inverse_DCT[ci] = method_ptr; + /* Create multiplier table from quant table. + * However, we can skip this if the component is uninteresting + * or if we already built the table. Also, if no quant table + * has yet been saved for the component, we leave the + * multiplier table all-zero; we'll be reading zeroes from the + * coefficient controller's buffer anyway. + */ + if (! compptr->component_needed || idct->cur_method[ci] == method) + continue; + qtbl = compptr->quant_table; + if (qtbl == NULL) /* happens if no data yet for component */ + continue; + idct->cur_method[ci] = method; + switch (method) { +#ifdef PROVIDE_ISLOW_TABLES + case JDCT_ISLOW: + { + /* For LL&M IDCT method, multipliers are equal to raw quantization + * coefficients, but are stored as ints to ensure access efficiency. + */ + ISLOW_MULT_TYPE * ismtbl = (ISLOW_MULT_TYPE *) compptr->dct_table; + for (i = 0; i < DCTSIZE2; i++) { + ismtbl[i] = (ISLOW_MULT_TYPE) qtbl->quantval[i]; + } + } + break; +#endif +#ifdef DCT_IFAST_SUPPORTED + case JDCT_IFAST: + { + /* For AA&N IDCT method, multipliers are equal to quantization + * coefficients scaled by scalefactor[row]*scalefactor[col], where + * scalefactor[0] = 1 + * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7 + * For integer operation, the multiplier table is to be scaled by + * IFAST_SCALE_BITS. + */ + IFAST_MULT_TYPE * ifmtbl = (IFAST_MULT_TYPE *) compptr->dct_table; +#define CONST_BITS 14 + static const INT16 aanscales[DCTSIZE2] = { + /* precomputed values scaled up by 14 bits */ + 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520, + 22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270, + 21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906, + 19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315, + 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520, + 12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552, + 8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446, + 4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247 + }; + SHIFT_TEMPS + + for (i = 0; i < DCTSIZE2; i++) { + ifmtbl[i] = (IFAST_MULT_TYPE) + DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i], + (INT32) aanscales[i]), + CONST_BITS-IFAST_SCALE_BITS); + } + } + break; +#endif +#ifdef DCT_FLOAT_SUPPORTED + case JDCT_FLOAT: + { + /* For float AA&N IDCT method, multipliers are equal to quantization + * coefficients scaled by scalefactor[row]*scalefactor[col], where + * scalefactor[0] = 1 + * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7 + */ + FLOAT_MULT_TYPE * fmtbl = (FLOAT_MULT_TYPE *) compptr->dct_table; + int row, col; + static const double aanscalefactor[DCTSIZE] = { + 1.0, 1.387039845, 1.306562965, 1.175875602, + 1.0, 0.785694958, 0.541196100, 0.275899379 + }; + + i = 0; + for (row = 0; row < DCTSIZE; row++) { + for (col = 0; col < DCTSIZE; col++) { + fmtbl[i] = (FLOAT_MULT_TYPE) + ((double) qtbl->quantval[i] * + aanscalefactor[row] * aanscalefactor[col]); + i++; + } + } + } + break; +#endif + default: + ERREXIT(cinfo, JERR_NOT_COMPILED); + break; + } + } +} + + +/* + * Initialize IDCT manager. + */ + +GLOBAL(void) +jinit_inverse_dct (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + idct_ptr idct; + int ci; + jpeg_component_info *compptr; + + idct = (idct_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(idct_controller)); + lossyd->idct_private = (void *) idct; + lossyd->idct_start_pass = start_pass; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Allocate and pre-zero a multiplier table for each component */ + compptr->dct_table = + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(multiplier_table)); + MEMZERO(compptr->dct_table, SIZEOF(multiplier_table)); + /* Mark multiplier table not yet set up for any method */ + idct->cur_method[ci] = -1; + } +} diff --git a/src/gdcmjpeg/jddiffct.c b/src/gdcmjpeg/jddiffct.c new file mode 100644 index 00000000..6dc61e44 --- /dev/null +++ b/src/gdcmjpeg/jddiffct.c @@ -0,0 +1,400 @@ +/* + * jddiffct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the [un]difference buffer controller for decompression. + * This controller is the top level of the lossless JPEG decompressor proper. + * The difference buffer lies between the entropy decoding and + * prediction/undifferencing steps. The undifference buffer lies between the + * prediction/undifferencing and scaling steps. + * + * In buffered-image mode, this controller is the interface between + * input-oriented processing and output-oriented processing. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" + + +#ifdef D_LOSSLESS_SUPPORTED + +/* Private buffer controller object */ + +typedef struct { + /* These variables keep track of the current location of the input side. */ + /* cinfo->input_iMCU_row is also used for this. */ + JDIMENSION MCU_ctr; /* counts MCUs processed in current row */ + unsigned int restart_rows_to_go; /* MCU-rows left in this restart interval */ + unsigned int MCU_vert_offset; /* counts MCU rows within iMCU row */ + unsigned int MCU_rows_per_iMCU_row; /* number of such rows needed */ + + /* The output side's location is represented by cinfo->output_iMCU_row. */ + + JDIFFARRAY diff_buf[MAX_COMPONENTS]; /* iMCU row of differences */ + JDIFFARRAY undiff_buf[MAX_COMPONENTS]; /* iMCU row of undiff'd samples */ + +#ifdef D_MULTISCAN_FILES_SUPPORTED + /* In multi-pass modes, we need a virtual sample array for each component. */ + jvirt_sarray_ptr whole_image[MAX_COMPONENTS]; +#endif +} d_diff_controller; + +typedef d_diff_controller * d_diff_ptr; + +/* Forward declarations */ +METHODDEF(int) decompress_data + JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); +#ifdef D_MULTISCAN_FILES_SUPPORTED +METHODDEF(int) output_data + JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); +#endif + + +LOCAL(void) +start_iMCU_row (j_decompress_ptr cinfo) +/* Reset within-iMCU-row counters for a new row (input side) */ +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff = (d_diff_ptr) losslsd->diff_private; + + /* In an interleaved scan, an MCU row is the same as an iMCU row. + * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows. + * But at the bottom of the image, process only what's left. + */ + if (cinfo->comps_in_scan > 1) { + diff->MCU_rows_per_iMCU_row = 1; + } else { + if (cinfo->input_iMCU_row < (cinfo->total_iMCU_rows-1)) + diff->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor; + else + diff->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height; + } + + diff->MCU_ctr = 0; + diff->MCU_vert_offset = 0; +} + + +/* + * Initialize for an input processing pass. + */ + +METHODDEF(void) +start_input_pass (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff = (d_diff_ptr) losslsd->diff_private; + + /* Check that the restart interval is an integer multiple of the number + * of MCU in an MCU-row. + */ + if (cinfo->restart_interval % cinfo->MCUs_per_row != 0) + ERREXIT2(cinfo, JERR_BAD_RESTART, + cinfo->restart_interval, cinfo->MCUs_per_row); + + /* Initialize restart counter */ + diff->restart_rows_to_go = cinfo->restart_interval / cinfo->MCUs_per_row; + + cinfo->input_iMCU_row = 0; + start_iMCU_row(cinfo); +} + + +/* + * Check for a restart marker & resynchronize decoder, undifferencer. + * Returns FALSE if must suspend. + */ + +METHODDEF(boolean) +process_restart (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff = (d_diff_ptr) losslsd->diff_private; + + if (! (*losslsd->entropy_process_restart) (cinfo)) + return FALSE; + + (*losslsd->predict_process_restart) (cinfo); + + /* Reset restart counter */ + diff->restart_rows_to_go = cinfo->restart_interval / cinfo->MCUs_per_row; + + return TRUE; +} + + +/* + * Initialize for an output processing pass. + */ + +METHODDEF(void) +start_output_pass (j_decompress_ptr cinfo) +{ + cinfo->output_iMCU_row = 0; +} + + +/* + * Decompress and return some data in the supplied buffer. + * Always attempts to emit one fully interleaved MCU row ("iMCU" row). + * Input and output must run in lockstep since we have only a one-MCU buffer. + * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED. + * + * NB: output_buf contains a plane for each component in image, + * which we index according to the component's SOF position. + */ + +METHODDEF(int) +decompress_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff = (d_diff_ptr) losslsd->diff_private; + JDIMENSION MCU_col_num; /* index of current MCU within row */ + JDIMENSION MCU_count; /* number of MCUs decoded */ + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + int comp, ci, row, prev_row; + unsigned int yoffset; + jpeg_component_info *compptr; + + /* Loop to process as much as one whole iMCU row */ + for (yoffset = diff->MCU_vert_offset; yoffset < diff->MCU_rows_per_iMCU_row; + yoffset++) { + + /* Process restart marker if needed; may have to suspend */ + if (cinfo->restart_interval) { + if (diff->restart_rows_to_go == 0) + if (! process_restart(cinfo)) + return JPEG_SUSPENDED; + } + + MCU_col_num = diff->MCU_ctr; + /* Try to fetch an MCU-row (or remaining portion of suspended MCU-row). */ + MCU_count = + (*losslsd->entropy_decode_mcus) (cinfo, + diff->diff_buf, yoffset, MCU_col_num, + cinfo->MCUs_per_row - MCU_col_num); + if (MCU_count != cinfo->MCUs_per_row - MCU_col_num) { + /* Suspension forced; update state counters and exit */ + diff->MCU_vert_offset = yoffset; + diff->MCU_ctr += MCU_count; + return JPEG_SUSPENDED; + } + + /* Account for restart interval (no-op if not using restarts) */ + diff->restart_rows_to_go--; + + /* Completed an MCU row, but perhaps not an iMCU row */ + diff->MCU_ctr = 0; + } + + /* + * Undifference and scale each scanline of the disassembled MCU-row + * separately. We do not process dummy samples at the end of a scanline + * or dummy rows at the end of the image. + */ + for (comp = 0; comp < cinfo->comps_in_scan; comp++) { + compptr = cinfo->cur_comp_info[comp]; + ci = compptr->component_index; + for (row = 0, prev_row = compptr->v_samp_factor - 1; + row < (cinfo->input_iMCU_row == last_iMCU_row ? + compptr->last_row_height : compptr->v_samp_factor); + prev_row = row, row++) { + (*losslsd->predict_undifference[ci]) (cinfo, ci, + diff->diff_buf[ci][row], + diff->undiff_buf[ci][prev_row], + diff->undiff_buf[ci][row], + compptr->width_in_data_units); + (*losslsd->scaler_scale) (cinfo, diff->undiff_buf[ci][row], + output_buf[ci][row], + compptr->width_in_data_units); + } + } + + /* Completed the iMCU row, advance counters for next one. + * + * NB: output_data will increment output_iMCU_row. + * This counter is not needed for the single-pass case + * or the input side of the multi-pass case. + */ + if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) { + start_iMCU_row(cinfo); + return JPEG_ROW_COMPLETED; + } + /* Completed the scan */ + (*cinfo->inputctl->finish_input_pass) (cinfo); + return JPEG_SCAN_COMPLETED; +} + + +/* + * Dummy consume-input routine for single-pass operation. + */ + +METHODDEF(int) +dummy_consume_data (j_decompress_ptr cinfo) +{ + (void)cinfo; + return JPEG_SUSPENDED; /* Always indicate nothing was done */ +} + + +#ifdef D_MULTISCAN_FILES_SUPPORTED + +/* + * Consume input data and store it in the full-image sample buffer. + * We read as much as one fully interleaved MCU row ("iMCU" row) per call, + * ie, v_samp_factor rows for each component in the scan. + * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED. + */ + +METHODDEF(int) +consume_data (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff = (d_diff_ptr) losslsd->diff_private; + /* JDIMENSION MCU_col_num; */ /* index of current MCU within row */ + /* JDIMENSION MCU_count; */ /* number of MCUs decoded */ + /* JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; */ + int comp, ci /* , yoffset, row, prev_row */; + JSAMPARRAY buffer[MAX_COMPS_IN_SCAN]; + jpeg_component_info *compptr; + + /* Align the virtual buffers for the components used in this scan. */ + for (comp = 0; comp < cinfo->comps_in_scan; comp++) { + compptr = cinfo->cur_comp_info[comp]; + ci = compptr->component_index; + buffer[ci] = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, diff->whole_image[ci], + cinfo->input_iMCU_row * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, TRUE); + } + + return decompress_data(cinfo, buffer); +} + + +/* + * Output some data from the full-image buffer sample in the multi-pass case. + * Always attempts to emit one fully interleaved MCU row ("iMCU" row). + * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED. + * + * NB: output_buf contains a plane for each component in image. + */ + +METHODDEF(int) +output_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff = (d_diff_ptr) losslsd->diff_private; + JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1; + int ci, samp_rows, row; + JSAMPARRAY buffer; + jpeg_component_info *compptr; + + /* Force some input to be done if we are getting ahead of the input. */ + while (cinfo->input_scan_number < cinfo->output_scan_number || + (cinfo->input_scan_number == cinfo->output_scan_number && + cinfo->input_iMCU_row <= cinfo->output_iMCU_row)) { + if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED) + return JPEG_SUSPENDED; + } + + /* OK, output from the virtual arrays. */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Align the virtual buffer for this component. */ + buffer = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, diff->whole_image[ci], + cinfo->output_iMCU_row * compptr->v_samp_factor, + (JDIMENSION) compptr->v_samp_factor, FALSE); + + if (cinfo->output_iMCU_row < last_iMCU_row) + samp_rows = compptr->v_samp_factor; + else { + /* NB: can't use last_row_height here; it is input-side-dependent! */ + samp_rows = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (samp_rows == 0) samp_rows = compptr->v_samp_factor; + } + + for (row = 0; row < samp_rows; row++) { + MEMCOPY(output_buf[ci][row], buffer[row], + compptr->width_in_data_units * SIZEOF(JSAMPLE)); + } + } + + if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows) + return JPEG_ROW_COMPLETED; + return JPEG_SCAN_COMPLETED; +} + +#endif /* D_MULTISCAN_FILES_SUPPORTED */ + + +/* + * Initialize difference buffer controller. + */ + +GLOBAL(void) +jinit_d_diff_controller (j_decompress_ptr cinfo, boolean need_full_buffer) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + d_diff_ptr diff; + int ci; + jpeg_component_info *compptr; + + diff = (d_diff_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(d_diff_controller)); + losslsd->diff_private = (void *) diff; + losslsd->diff_start_input_pass = start_input_pass; + losslsd->pub.start_output_pass = start_output_pass; + + /* Create the [un]difference buffers. */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + diff->diff_buf[ci] = (*cinfo->mem->alloc_darray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) compptr->v_samp_factor); + diff->undiff_buf[ci] = (*cinfo->mem->alloc_darray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) compptr->v_samp_factor); + } + + if (need_full_buffer) { +#ifdef D_MULTISCAN_FILES_SUPPORTED + /* Allocate a full-image virtual array for each component. */ + int access_rows; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + access_rows = compptr->v_samp_factor; + diff->whole_image[ci] = (*cinfo->mem->request_virt_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, + (JDIMENSION) jround_up((long) compptr->width_in_data_units, + (long) compptr->h_samp_factor), + (JDIMENSION) jround_up((long) compptr->height_in_data_units, + (long) compptr->v_samp_factor), + (JDIMENSION) access_rows); + } + losslsd->pub.consume_data = consume_data; + losslsd->pub.decompress_data = output_data; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + losslsd->pub.consume_data = dummy_consume_data; + losslsd->pub.decompress_data = decompress_data; + diff->whole_image[0] = NULL; /* flag for no virtual arrays */ + } +} + +#endif /* D_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jdhuff.c b/src/gdcmjpeg/jdhuff.c new file mode 100644 index 00000000..54a82724 --- /dev/null +++ b/src/gdcmjpeg/jdhuff.c @@ -0,0 +1,321 @@ +/* + * jdhuff.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy decoding routines which are shared + * by the sequential, progressive and lossless decoders. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ +#include "jlossls.h" /* Private declarations for lossless codec */ +#include "jdhuff.h" /* Declarations shared with jd*huff.c */ + + +/* + * Compute the derived values for a Huffman table. + * This routine also performs some validation checks on the table. + */ + +GLOBAL(void) +jpeg_make_d_derived_tbl (j_decompress_ptr cinfo, boolean isDC, int tblno, + d_derived_tbl ** pdtbl) +{ + JHUFF_TBL *htbl; + d_derived_tbl *dtbl; + int p, i, l, si, numsymbols; + int lookbits, ctr; + char huffsize[257]; + unsigned int huffcode[257]; + unsigned int code; + + /* Note that huffsize[] and huffcode[] are filled in code-length order, + * paralleling the order of the symbols themselves in htbl->huffval[]. + */ + + /* Find the input Huffman table */ + if (tblno < 0 || tblno >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno); + htbl = + isDC ? cinfo->dc_huff_tbl_ptrs[tblno] : cinfo->ac_huff_tbl_ptrs[tblno]; + if (htbl == NULL) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno); + + /* Allocate a workspace if we haven't already done so. */ + if (*pdtbl == NULL) + *pdtbl = (d_derived_tbl *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(d_derived_tbl)); + dtbl = *pdtbl; + dtbl->pub = htbl; /* fill in back link */ + + /* Figure C.1: make table of Huffman code length for each symbol */ + + p = 0; + for (l = 1; l <= 16; l++) { + i = (int) htbl->bits[l]; + if (i < 0 || p + i > 256) /* protect against table overrun */ + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + while (i--) + huffsize[p++] = (char) l; + } + huffsize[p] = 0; + numsymbols = p; + + /* Figure C.2: generate the codes themselves */ + /* We also validate that the counts represent a legal Huffman code tree. */ + + code = 0; + si = huffsize[0]; + p = 0; + while (huffsize[p]) { + while (((int) huffsize[p]) == si) { + huffcode[p++] = code; + code++; + } + /* code is now 1 more than the last code used for codelength si; but + * it must still fit in si bits, since no code is allowed to be all ones. + * BUG FIX 2001-09-03: Comparison must be >, not >= + */ + if (((INT32) code) > (((INT32) 1) << si)) + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + code <<= 1; + si++; + } + + /* Figure F.15: generate decoding tables for bit-sequential decoding */ + + p = 0; + for (l = 1; l <= 16; l++) { + if (htbl->bits[l]) { + /* valoffset[l] = huffval[] index of 1st symbol of code length l, + * minus the minimum code of length l + */ + dtbl->valoffset[l] = (INT32) p - (INT32) huffcode[p]; + p += htbl->bits[l]; + dtbl->maxcode[l] = huffcode[p-1]; /* maximum code of length l */ + } else { + dtbl->maxcode[l] = -1; /* -1 if no codes of this length */ + } + } + dtbl->maxcode[17] = 0xFFFFFL; /* ensures jpeg_huff_decode terminates */ + + /* Compute lookahead tables to speed up decoding. + * First we set all the table entries to 0, indicating "too long"; + * then we iterate through the Huffman codes that are short enough and + * fill in all the entries that correspond to bit sequences starting + * with that code. + */ + + MEMZERO(dtbl->look_nbits, SIZEOF(dtbl->look_nbits)); + + p = 0; + for (l = 1; l <= HUFF_LOOKAHEAD; l++) { + for (i = 1; i <= (int) htbl->bits[l]; i++, p++) { + /* l = current code's length, p = its index in huffcode[] & huffval[]. */ + /* Generate left-justified code followed by all possible bit sequences */ + lookbits = huffcode[p] << (HUFF_LOOKAHEAD-l); + for (ctr = 1 << (HUFF_LOOKAHEAD-l); ctr > 0; ctr--) { + dtbl->look_nbits[lookbits] = l; + dtbl->look_sym[lookbits] = htbl->huffval[p]; + lookbits++; + } + } + } + + /* Validate symbols as being reasonable. + * For AC tables, we make no check, but accept all byte values 0..255. + * For DC tables, we require the symbols to be in range 0..16. + * (Tighter bounds could be applied depending on the data depth and mode, + * but this is sufficient to ensure safe decoding.) + */ + if (isDC) { + for (i = 0; i < numsymbols; i++) { + int sym = htbl->huffval[i]; + if (sym < 0 || sym > 16) +/* The following is needed to be able to read certain Philips DICOM MRI images */ +#if BITS_IN_JSAMPLE == 12 + htbl->huffval[i]=15; +#else + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); +#endif /* BITS_IN_JSAMPLE == 12 */ + } + } +} + + +/* + * Out-of-line code for bit fetching. + * See jdhuff.h for info about usage. + * Note: current values of get_buffer and bits_left are passed as parameters, + * but are returned in the corresponding fields of the state struct. + * + * On most machines MIN_GET_BITS should be 25 to allow the full 32-bit width + * of get_buffer to be used. (On machines with wider words, an even larger + * buffer could be used.) However, on some machines 32-bit shifts are + * quite slow and take time proportional to the number of places shifted. + * (This is true with most PC compilers, for instance.) In this case it may + * be a win to set MIN_GET_BITS to the minimum value of 15. This reduces the + * average shift distance at the cost of more calls to jpeg_fill_bit_buffer. + */ + +#ifdef SLOW_SHIFT_32 +#define MIN_GET_BITS 15 /* minimum allowable value */ +#else +#define MIN_GET_BITS (BIT_BUF_SIZE-7) +#endif + + +GLOBAL(boolean) +jpeg_fill_bit_buffer (bitread_working_state * state, + register bit_buf_type get_buffer, register int bits_left, + int nbits) +/* Load up the bit buffer to a depth of at least nbits */ +{ + /* Copy heavily used state fields into locals (hopefully registers) */ + register const JOCTET * next_input_byte = state->next_input_byte; + register size_t bytes_in_buffer = state->bytes_in_buffer; + j_decompress_ptr cinfo = state->cinfo; + + /* Attempt to load at least MIN_GET_BITS bits into get_buffer. */ + /* (It is assumed that no request will be for more than that many bits.) */ + /* We fail to do so only if we hit a marker or are forced to suspend. */ + + if (cinfo->unread_marker == 0) { /* cannot advance past a marker */ + while (bits_left < MIN_GET_BITS) { + register int c; + + /* Attempt to read a byte */ + if (bytes_in_buffer == 0) { + if (! (*cinfo->src->fill_input_buffer) (cinfo)) + return FALSE; + next_input_byte = cinfo->src->next_input_byte; + bytes_in_buffer = cinfo->src->bytes_in_buffer; + } + bytes_in_buffer--; + c = GETJOCTET(*next_input_byte++); + + /* If it's 0xFF, check and discard stuffed zero byte */ + if (c == 0xFF) { + /* Loop here to discard any padding FF's on terminating marker, + * so that we can save a valid unread_marker value. NOTE: we will + * accept multiple FF's followed by a 0 as meaning a single FF data + * byte. This data pattern is not valid according to the standard. + */ + do { + if (bytes_in_buffer == 0) { + if (! (*cinfo->src->fill_input_buffer) (cinfo)) + return FALSE; + next_input_byte = cinfo->src->next_input_byte; + bytes_in_buffer = cinfo->src->bytes_in_buffer; + } + bytes_in_buffer--; + c = GETJOCTET(*next_input_byte++); + } while (c == 0xFF); + + if (c == 0) { + /* Found FF/00, which represents an FF data byte */ + c = 0xFF; + } else { + /* Oops, it's actually a marker indicating end of compressed data. + * Save the marker code for later use. + * Fine point: it might appear that we should save the marker into + * bitread working state, not straight into permanent state. But + * once we have hit a marker, we cannot need to suspend within the + * current MCU, because we will read no more bytes from the data + * source. So it is OK to update permanent state right away. + */ + cinfo->unread_marker = c; + /* See if we need to insert some fake zero bits. */ + goto no_more_bytes; + } + } + + /* OK, load c into get_buffer */ + get_buffer = (get_buffer << 8) | c; + bits_left += 8; + } /* end while */ + } else { + no_more_bytes: + /* We get here if we've read the marker that terminates the compressed + * data segment. There should be enough bits in the buffer register + * to satisfy the request; if so, no problem. + */ + if (nbits > bits_left) { + /* Uh-oh. Report corrupted data to user and stuff zeroes into + * the data stream, so that we can produce some kind of image. + * We use a nonvolatile flag to ensure that only one warning message + * appears per data segment. + */ + huffd_common_ptr huffd; + if (cinfo->process == JPROC_LOSSLESS) + huffd = (huffd_common_ptr) ((j_lossless_d_ptr) cinfo->codec)->entropy_private; + else + huffd = (huffd_common_ptr) ((j_lossy_d_ptr) cinfo->codec)->entropy_private; + if (! huffd->insufficient_data) { + WARNMS(cinfo, JWRN_HIT_MARKER); + huffd->insufficient_data = TRUE; + } + /* Fill the buffer with zero bits */ + get_buffer <<= MIN_GET_BITS - bits_left; + bits_left = MIN_GET_BITS; + } + } + + /* Unload the local registers */ + state->next_input_byte = next_input_byte; + state->bytes_in_buffer = bytes_in_buffer; + state->get_buffer = get_buffer; + state->bits_left = bits_left; + + return TRUE; +} + + +/* + * Out-of-line code for Huffman code decoding. + * See jdhuff.h for info about usage. + */ + +GLOBAL(int) +jpeg_huff_decode (bitread_working_state * state, + register bit_buf_type get_buffer, register int bits_left, + d_derived_tbl * htbl, int min_bits) +{ + register int l = min_bits; + register INT32 code; + + /* HUFF_DECODE has determined that the code is at least min_bits */ + /* bits long, so fetch that many bits in one swoop. */ + + CHECK_BIT_BUFFER(*state, l, return -1); + code = GET_BITS(l); + + /* Collect the rest of the Huffman code one bit at a time. */ + /* This is per Figure F.16 in the JPEG spec. */ + + while (code > htbl->maxcode[l]) { + code <<= 1; + CHECK_BIT_BUFFER(*state, 1, return -1); + code |= GET_BITS(1); + l++; + } + + /* Unload the local registers */ + state->get_buffer = get_buffer; + state->bits_left = bits_left; + + /* With garbage input we may reach the sentinel value l = 17. */ + + if (l > 16) { + WARNMS(state->cinfo, JWRN_HUFF_BAD_CODE); + return 0; /* fake a zero as the safest result */ + } + + return htbl->pub->huffval[ (int) (code + htbl->valoffset[l]) ]; +} diff --git a/src/gdcmjpeg/jdhuff.h b/src/gdcmjpeg/jdhuff.h new file mode 100644 index 00000000..90746562 --- /dev/null +++ b/src/gdcmjpeg/jdhuff.h @@ -0,0 +1,229 @@ +/* + * jdhuff.h + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains declarations for Huffman entropy decoding routines + * that are shared between the sequential decoder (jdhuff.c), the + * progressive decoder (jdphuff.c) and the lossless decoder (jdlhuff.c). + * No other modules need to see these. + */ + +/* Short forms of external names for systems with brain-damaged linkers. */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jpeg_make_d_derived_tbl jMkDDerived +#define jpeg_fill_bit_buffer jFilBitBuf +#define jpeg_huff_decode jHufDecode +#endif /* NEED_SHORT_EXTERNAL_NAMES */ + + +/* Derived data constructed for each Huffman table */ + +#define HUFF_LOOKAHEAD 8 /* # of bits of lookahead */ + +typedef struct { + /* Basic tables: (element [0] of each array is unused) */ + INT32 maxcode[18]; /* largest code of length k (-1 if none) */ + /* (maxcode[17] is a sentinel to ensure jpeg_huff_decode terminates) */ + INT32 valoffset[17]; /* huffval[] offset for codes of length k */ + /* valoffset[k] = huffval[] index of 1st symbol of code length k, less + * the smallest code of length k; so given a code of length k, the + * corresponding symbol is huffval[code + valoffset[k]] + */ + + /* Link to public Huffman table (needed only in jpeg_huff_decode) */ + JHUFF_TBL *pub; + + /* Lookahead tables: indexed by the next HUFF_LOOKAHEAD bits of + * the input data stream. If the next Huffman code is no more + * than HUFF_LOOKAHEAD bits long, we can obtain its length and + * the corresponding symbol directly from these tables. + */ + int look_nbits[1< 32 bits on your machine, and shifting/masking longs is + * reasonably fast, making bit_buf_type be long and setting BIT_BUF_SIZE + * appropriately should be a win. Unfortunately we can't define the size + * with something like #define BIT_BUF_SIZE (sizeof(bit_buf_type)*8) + * because not all machines measure sizeof in 8-bit bytes. + */ + +typedef struct { /* Bitreading state saved across MCUs */ + bit_buf_type get_buffer; /* current bit-extraction buffer */ + int bits_left; /* # of unused bits in it */ +} bitread_perm_state; + +typedef struct { /* Bitreading working state within an MCU */ + /* Current data source location */ + /* We need a copy, rather than munging the original, in case of suspension */ + const JOCTET * next_input_byte; /* => next byte to read from source */ + size_t bytes_in_buffer; /* # of bytes remaining in source buffer */ + /* Bit input buffer --- note these values are kept in register variables, + * not in this struct, inside the inner loops. + */ + bit_buf_type get_buffer; /* current bit-extraction buffer */ + int bits_left; /* # of unused bits in it */ + /* Pointer needed by jpeg_fill_bit_buffer. */ + j_decompress_ptr cinfo; /* back link to decompress master record */ +} bitread_working_state; + +/* Macros to declare and load/save bitread local variables. */ +#define BITREAD_STATE_VARS \ + register bit_buf_type get_buffer; \ + register int bits_left; \ + bitread_working_state br_state + +#define BITREAD_LOAD_STATE(cinfop,permstate) \ + br_state.cinfo = cinfop; \ + br_state.next_input_byte = cinfop->src->next_input_byte; \ + br_state.bytes_in_buffer = cinfop->src->bytes_in_buffer; \ + get_buffer = permstate.get_buffer; \ + bits_left = permstate.bits_left; + +#define BITREAD_SAVE_STATE(cinfop,permstate) \ + cinfop->src->next_input_byte = br_state.next_input_byte; \ + cinfop->src->bytes_in_buffer = br_state.bytes_in_buffer; \ + permstate.get_buffer = get_buffer; \ + permstate.bits_left = bits_left + +/* + * These macros provide the in-line portion of bit fetching. + * Use CHECK_BIT_BUFFER to ensure there are N bits in get_buffer + * before using GET_BITS, PEEK_BITS, or DROP_BITS. + * The variables get_buffer and bits_left are assumed to be locals, + * but the state struct might not be (jpeg_huff_decode needs this). + * CHECK_BIT_BUFFER(state,n,action); + * Ensure there are N bits in get_buffer; if suspend, take action. + * val = GET_BITS(n); + * Fetch next N bits. + * val = PEEK_BITS(n); + * Fetch next N bits without removing them from the buffer. + * DROP_BITS(n); + * Discard next N bits. + * The value N should be a simple variable, not an expression, because it + * is evaluated multiple times. + */ + +#define CHECK_BIT_BUFFER(state,nbits,action) \ + { if (bits_left < (nbits)) { \ + if (! jpeg_fill_bit_buffer(&(state),get_buffer,bits_left,nbits)) \ + { action; } \ + get_buffer = (state).get_buffer; bits_left = (state).bits_left; } } + +#define GET_BITS(nbits) \ + (((int) (get_buffer >> (bits_left -= (nbits)))) & ((1<<(nbits))-1)) + +#define PEEK_BITS(nbits) \ + (((int) (get_buffer >> (bits_left - (nbits)))) & ((1<<(nbits))-1)) + +#define DROP_BITS(nbits) \ + (bits_left -= (nbits)) + +/* Load up the bit buffer to a depth of at least nbits */ +EXTERN(boolean) jpeg_fill_bit_buffer + JPP((bitread_working_state * state, register bit_buf_type get_buffer, + register int bits_left, int nbits)); + + +/* + * Code for extracting next Huffman-coded symbol from input bit stream. + * Again, this is time-critical and we make the main paths be macros. + * + * We use a lookahead table to process codes of up to HUFF_LOOKAHEAD bits + * without looping. Usually, more than 95% of the Huffman codes will be 8 + * or fewer bits long. The few overlength codes are handled with a loop, + * which need not be inline code. + * + * Notes about the HUFF_DECODE macro: + * 1. Near the end of the data segment, we may fail to get enough bits + * for a lookahead. In that case, we do it the hard way. + * 2. If the lookahead table contains no entry, the next code must be + * more than HUFF_LOOKAHEAD bits long. + * 3. jpeg_huff_decode returns -1 if forced to suspend. + */ + +#define HUFF_DECODE(result,state,htbl,failaction,slowlabel) \ +{ register int nb, look; \ + if (bits_left < HUFF_LOOKAHEAD) { \ + if (! jpeg_fill_bit_buffer(&state,get_buffer,bits_left, 0)) {failaction;} \ + get_buffer = state.get_buffer; bits_left = state.bits_left; \ + if (bits_left < HUFF_LOOKAHEAD) { \ + nb = 1; goto slowlabel; \ + } \ + } \ + look = PEEK_BITS(HUFF_LOOKAHEAD); \ + if ((nb = htbl->look_nbits[look]) != 0) { \ + DROP_BITS(nb); \ + result = htbl->look_sym[look]; \ + } else { \ + nb = HUFF_LOOKAHEAD+1; \ +slowlabel: \ + if ((result=jpeg_huff_decode(&state,get_buffer,bits_left,htbl,nb)) < 0) \ + { failaction; } \ + get_buffer = state.get_buffer; bits_left = state.bits_left; \ + } \ +} + +/* Out-of-line case for Huffman code fetching */ +EXTERN(int) jpeg_huff_decode + JPP((bitread_working_state * state, register bit_buf_type get_buffer, + register int bits_left, d_derived_tbl * htbl, int min_bits)); + + +/* Common fields between sequential, progressive and lossless Huffman entropy + * decoder master structs. + */ + +#define huffd_common_fields \ + boolean insufficient_data; /* set TRUE after emmitting warning */ \ + /* These fields are loaded into local variables at start of each MCU. \ + * In case of suspension, we exit WITHOUT updating them. \ + */ \ + bitread_perm_state bitstate /* Bit buffer at start of MCU */ + +/* Routines that are to be used by any or all of the entropy decoders are + * declared to receive a pointer to this structure. There are no actual + * instances of huffd_common_struct, only of shuff_entropy_decoder, + * phuff_entropy_decoder and lhuff_entropy_decoder. + */ +struct huffd_common_struct { + huffd_common_fields; /* Fields common to all decoder struct types */ + /* Additional fields follow in an actual shuff_entropy_decoder, + * phuff_entropy_decoder or lhuff_entropy_decoder struct. All four structs + * must agree on these initial fields! (This would be a lot cleaner in C++.) + */ +}; + +typedef struct huffd_common_struct * huffd_common_ptr; diff --git a/src/gdcmjpeg/jdinput.c b/src/gdcmjpeg/jdinput.c new file mode 100644 index 00000000..8cb0f22d --- /dev/null +++ b/src/gdcmjpeg/jdinput.c @@ -0,0 +1,347 @@ +/* + * jdinput.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains input control logic for the JPEG decompressor. + * These routines are concerned with controlling the decompressor's input + * processing (marker reading and coefficient/difference decoding). + * The actual input reading is done in jdmarker.c, jdhuff.c, jdphuff.c, + * and jdlhuff.c. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Private state */ + +typedef struct { + struct jpeg_input_controller pub; /* public fields */ + + boolean inheaders; /* TRUE until first SOS is reached */ +} my_input_controller; + +typedef my_input_controller * my_inputctl_ptr; + + +/* Forward declarations */ +METHODDEF(int) consume_markers JPP((j_decompress_ptr cinfo)); + + +/* + * Routines to calculate various quantities related to the size of the image. + */ + +LOCAL(void) +initial_setup (j_decompress_ptr cinfo) +/* Called once, when first SOS marker is reached */ +{ + int ci; + jpeg_component_info *compptr; + + /* Make sure image isn't bigger than I can handle */ + if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION || + (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION) + ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION); + + if (cinfo->process == JPROC_LOSSLESS) { + /* If precision > compiled-in value, we must downscale */ + if (cinfo->data_precision > BITS_IN_JSAMPLE) + WARNMS2(cinfo, JWRN_MUST_DOWNSCALE, + cinfo->data_precision, BITS_IN_JSAMPLE); + } + else { /* Lossy processes */ + /* For now, precision must match compiled-in value... */ + if (cinfo->data_precision != BITS_IN_JSAMPLE) + ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision); + } + + /* Check that number of components won't exceed internal array sizes */ + if (cinfo->num_components > MAX_COMPONENTS) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components, + MAX_COMPONENTS); + + /* Compute maximum sampling factors; check factor validity */ + cinfo->max_h_samp_factor = 1; + cinfo->max_v_samp_factor = 1; + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR || + compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR) + ERREXIT(cinfo, JERR_BAD_SAMPLING); + cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor, + compptr->h_samp_factor); + cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor, + compptr->v_samp_factor); + } + + /* We initialize codec_data_unit and min_codec_data_unit to data_unit. + * In the full decompressor, this will be overridden by jdmaster.c; + * but in the transcoder, jdmaster.c is not used, so we must do it here. + */ + cinfo->min_codec_data_unit = cinfo->data_unit; + + /* Compute dimensions of components */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + compptr->codec_data_unit = cinfo->data_unit; + /* Size in data units */ + compptr->width_in_data_units = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, + (long) (cinfo->max_h_samp_factor * cinfo->data_unit)); + compptr->height_in_data_units = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, + (long) (cinfo->max_v_samp_factor * cinfo->data_unit)); + /* downsampled_width and downsampled_height will also be overridden by + * jdmaster.c if we are doing full decompression. The transcoder library + * doesn't use these values, but the calling application might. + */ + /* Size in samples */ + compptr->downsampled_width = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor, + (long) cinfo->max_h_samp_factor); + compptr->downsampled_height = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor, + (long) cinfo->max_v_samp_factor); + /* Mark component needed, until color conversion says otherwise */ + compptr->component_needed = TRUE; + /* Mark no quantization table yet saved for component */ + compptr->quant_table = NULL; + } + + /* Compute number of fully interleaved MCU rows. */ + cinfo->total_iMCU_rows = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, + (long) (cinfo->max_v_samp_factor*cinfo->data_unit)); + + /* Decide whether file contains multiple scans */ + if (cinfo->comps_in_scan < cinfo->num_components || + cinfo->process == JPROC_PROGRESSIVE) + cinfo->inputctl->has_multiple_scans = TRUE; + else + cinfo->inputctl->has_multiple_scans = FALSE; +} + + +LOCAL(void) +per_scan_setup (j_decompress_ptr cinfo) +/* Do computations that are needed before processing a JPEG scan */ +/* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */ +{ + int ci, mcublks, tmp; + jpeg_component_info *compptr; + + if (cinfo->comps_in_scan == 1) { + + /* Noninterleaved (single-component) scan */ + compptr = cinfo->cur_comp_info[0]; + + /* Overall image size in MCUs */ + cinfo->MCUs_per_row = compptr->width_in_data_units; + cinfo->MCU_rows_in_scan = compptr->height_in_data_units; + + /* For noninterleaved scan, always one data unit per MCU */ + compptr->MCU_width = 1; + compptr->MCU_height = 1; + compptr->MCU_data_units = 1; + compptr->MCU_sample_width = compptr->codec_data_unit; + compptr->last_col_width = 1; + /* For noninterleaved scans, it is convenient to define last_row_height + * as the number of data unit rows present in the last iMCU row. + */ + tmp = (int) (compptr->height_in_data_units % compptr->v_samp_factor); + if (tmp == 0) tmp = compptr->v_samp_factor; + compptr->last_row_height = tmp; + + /* Prepare array describing MCU composition */ + cinfo->data_units_in_MCU = 1; + cinfo->MCU_membership[0] = 0; + + } else { + + /* Interleaved (multi-component) scan */ + if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN) + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan, + MAX_COMPS_IN_SCAN); + + /* Overall image size in MCUs */ + cinfo->MCUs_per_row = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width, + (long) (cinfo->max_h_samp_factor*cinfo->data_unit)); + cinfo->MCU_rows_in_scan = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, + (long) (cinfo->max_v_samp_factor*cinfo->data_unit)); + + cinfo->data_units_in_MCU = 0; + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + /* Sampling factors give # of data units of component in each MCU */ + compptr->MCU_width = compptr->h_samp_factor; + compptr->MCU_height = compptr->v_samp_factor; + compptr->MCU_data_units = compptr->MCU_width * compptr->MCU_height; + compptr->MCU_sample_width = compptr->MCU_width * compptr->codec_data_unit; + /* Figure number of non-dummy data units in last MCU column & row */ + tmp = (int) (compptr->width_in_data_units % compptr->MCU_width); + if (tmp == 0) tmp = compptr->MCU_width; + compptr->last_col_width = tmp; + tmp = (int) (compptr->height_in_data_units % compptr->MCU_height); + if (tmp == 0) tmp = compptr->MCU_height; + compptr->last_row_height = tmp; + /* Prepare array describing MCU composition */ + mcublks = compptr->MCU_data_units; + if (cinfo->data_units_in_MCU + mcublks > D_MAX_DATA_UNITS_IN_MCU) + ERREXIT(cinfo, JERR_BAD_MCU_SIZE); + while (mcublks-- > 0) { + cinfo->MCU_membership[cinfo->data_units_in_MCU++] = ci; + } + } + + } +} + + +/* + * Initialize the input modules to read a scan of compressed data. + * The first call to this is done by jdmaster.c after initializing + * the entire decompressor (during jpeg_start_decompress). + * Subsequent calls come from consume_markers, below. + */ + +METHODDEF(void) +start_input_pass (j_decompress_ptr cinfo) +{ + per_scan_setup(cinfo); + (*cinfo->codec->start_input_pass) (cinfo); + cinfo->inputctl->consume_input = cinfo->codec->consume_data; +} + + +/* + * Finish up after inputting a compressed-data scan. + * This is called by the coefficient controller after it's read all + * the expected data of the scan. + */ + +METHODDEF(void) +finish_input_pass (j_decompress_ptr cinfo) +{ + cinfo->inputctl->consume_input = consume_markers; +} + + +/* + * Read JPEG markers before, between, or after compressed-data scans. + * Change state as necessary when a new scan is reached. + * Return value is JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. + * + * The consume_input method pointer points either here or to the + * coefficient controller's consume_data routine, depending on whether + * we are reading a compressed data segment or inter-segment markers. + */ + +METHODDEF(int) +consume_markers (j_decompress_ptr cinfo) +{ + my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl; + int val; + + if (inputctl->pub.eoi_reached) /* After hitting EOI, read no further */ + return JPEG_REACHED_EOI; + + val = (*cinfo->marker->read_markers) (cinfo); + + switch (val) { + case JPEG_REACHED_SOS: /* Found SOS */ + if (inputctl->inheaders) { /* 1st SOS */ + initial_setup(cinfo); + /* + * Initialize the decompression codec. We need to do this here so that + * any codec-specific fields and function pointers are available to + * the rest of the library. + */ + jinit_d_codec(cinfo); + inputctl->inheaders = FALSE; + /* Note: start_input_pass must be called by jdmaster.c + * before any more input can be consumed. jdapimin.c is + * responsible for enforcing this sequencing. + */ + } else { /* 2nd or later SOS marker */ + if (! inputctl->pub.has_multiple_scans) + ERREXIT(cinfo, JERR_EOI_EXPECTED); /* Oops, I wasn't expecting this! */ + start_input_pass(cinfo); + } + break; + case JPEG_REACHED_EOI: /* Found EOI */ + inputctl->pub.eoi_reached = TRUE; + if (inputctl->inheaders) { /* Tables-only datastream, apparently */ + if (cinfo->marker->saw_SOF) + ERREXIT(cinfo, JERR_SOF_NO_SOS); + } else { + /* Prevent infinite loop in coef ctlr's decompress_data routine + * if user set output_scan_number larger than number of scans. + */ + if (cinfo->output_scan_number > cinfo->input_scan_number) + cinfo->output_scan_number = cinfo->input_scan_number; + } + break; + case JPEG_SUSPENDED: + break; + } + + return val; +} + + +/* + * Reset state to begin a fresh datastream. + */ + +METHODDEF(void) +reset_input_controller (j_decompress_ptr cinfo) +{ + my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl; + + inputctl->pub.consume_input = consume_markers; + inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */ + inputctl->pub.eoi_reached = FALSE; + inputctl->inheaders = TRUE; + /* Reset other modules */ + (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo); + (*cinfo->marker->reset_marker_reader) (cinfo); + /* Reset progression state -- would be cleaner if entropy decoder did this */ + cinfo->coef_bits = NULL; +} + + +/* + * Initialize the input controller module. + * This is called only once, when the decompression object is created. + */ + +GLOBAL(void) +jinit_input_controller (j_decompress_ptr cinfo) +{ + my_inputctl_ptr inputctl; + + /* Create subobject in permanent pool */ + inputctl = (my_inputctl_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(my_input_controller)); + cinfo->inputctl = (struct jpeg_input_controller *) inputctl; + /* Initialize method pointers */ + inputctl->pub.consume_input = consume_markers; + inputctl->pub.reset_input_controller = reset_input_controller; + inputctl->pub.start_input_pass = start_input_pass; + inputctl->pub.finish_input_pass = finish_input_pass; + /* Initialize state: can't use reset_input_controller since we don't + * want to try to reset other modules yet. + */ + inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */ + inputctl->pub.eoi_reached = FALSE; + inputctl->inheaders = TRUE; +} diff --git a/src/gdcmjpeg/jdlhuff.c b/src/gdcmjpeg/jdlhuff.c new file mode 100644 index 00000000..2ee9f28a --- /dev/null +++ b/src/gdcmjpeg/jdlhuff.c @@ -0,0 +1,291 @@ +/* + * jdlhuff.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy decoding routines for lossless JPEG. + * + * Much of the complexity here has to do with supporting input suspension. + * If the data source module demands suspension, we want to be able to back + * up to the start of the current MCU. To do this, we copy state variables + * into local working storage, and update them back to the permanent + * storage only upon successful completion of an MCU. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ +#include "jdhuff.h" /* Declarations shared with jd*huff.c */ + + +#ifdef D_LOSSLESS_SUPPORTED + +typedef struct { + int ci, yoffset, MCU_width; +} lhd_output_ptr_info; + +/* + * Private entropy decoder object for lossless Huffman decoding. + */ + +typedef struct { + huffd_common_fields; /* Fields shared with other entropy decoders */ + + /* Pointers to derived tables (these workspaces have image lifespan) */ + d_derived_tbl * derived_tbls[NUM_HUFF_TBLS]; + + /* Precalculated info set up by start_pass for use in decode_mcus: */ + + /* Pointers to derived tables to be used for each data unit within an MCU */ + d_derived_tbl * cur_tbls[D_MAX_DATA_UNITS_IN_MCU]; + + /* Pointers to the proper output difference row for each group of data units + * within an MCU. For each component, there are Vi groups of Hi data units. + */ + JDIFFROW output_ptr[D_MAX_DATA_UNITS_IN_MCU]; + + /* Number of output pointers in use for the current MCU. This is the sum + * of all Vi in the MCU. + */ + int num_output_ptrs; + + /* Information used for positioning the output pointers within the output + * difference rows. + */ + lhd_output_ptr_info output_ptr_info[D_MAX_DATA_UNITS_IN_MCU]; + + /* Index of the proper output pointer for each data unit within an MCU */ + int output_ptr_index[D_MAX_DATA_UNITS_IN_MCU]; + +} lhuff_entropy_decoder; + +typedef lhuff_entropy_decoder * lhuff_entropy_ptr; + + +/* + * Initialize for a Huffman-compressed scan. + */ + +METHODDEF(void) +start_pass_lhuff_decoder (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsd->entropy_private; + int ci, dctbl, sampn, ptrn, yoffset, xoffset; + jpeg_component_info * compptr; + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + dctbl = compptr->dc_tbl_no; + /* Make sure requested tables are present */ + if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS || + cinfo->dc_huff_tbl_ptrs[dctbl] == NULL) + ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl); + /* Compute derived values for Huffman tables */ + /* We may do this more than once for a table, but it's not expensive */ + jpeg_make_d_derived_tbl(cinfo, TRUE, dctbl, + & entropy->derived_tbls[dctbl]); + } + + /* Precalculate decoding info for each sample in an MCU of this scan */ + for (sampn = 0, ptrn = 0; sampn < cinfo->data_units_in_MCU;) { + compptr = cinfo->cur_comp_info[cinfo->MCU_membership[sampn]]; + ci = compptr->component_index; + for (yoffset = 0; yoffset < compptr->MCU_height; yoffset++, ptrn++) { + /* Precalculate the setup info for each output pointer */ + entropy->output_ptr_info[ptrn].ci = ci; + entropy->output_ptr_info[ptrn].yoffset = yoffset; + entropy->output_ptr_info[ptrn].MCU_width = compptr->MCU_width; + for (xoffset = 0; xoffset < compptr->MCU_width; xoffset++, sampn++) { + /* Precalculate the output pointer index for each sample */ + entropy->output_ptr_index[sampn] = ptrn; + /* Precalculate which table to use for each sample */ + entropy->cur_tbls[sampn] = entropy->derived_tbls[compptr->dc_tbl_no]; + } + } + } + entropy->num_output_ptrs = ptrn; + + /* Initialize bitread state variables */ + entropy->bitstate.bits_left = 0; + entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */ + entropy->insufficient_data = FALSE; +} + + +/* + * Figure F.12: extend sign bit. + * On some machines, a shift and add will be faster than a table lookup. + */ + +#ifdef AVOID_TABLES + +#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x)) + +#else + +#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x)) + +static const int extend_test[16] = /* entry n is 2**(n-1) */ + { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, + 0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 }; + +static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */ + { 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1, + ((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1, + ((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1, + ((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 }; + +#endif /* AVOID_TABLES */ + + +/* + * Check for a restart marker & resynchronize decoder. + * Returns FALSE if must suspend. + */ + +METHODDEF(boolean) +process_restart (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsd->entropy_private; + /* int ci; */ + + /* Throw away any unused bits remaining in bit buffer; */ + /* include any full bytes in next_marker's count of discarded bytes */ + cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8; + entropy->bitstate.bits_left = 0; + + /* Advance past the RSTn marker */ + if (! (*cinfo->marker->read_restart_marker) (cinfo)) + return FALSE; + + /* Reset out-of-data flag, unless read_restart_marker left us smack up + * against a marker. In that case we will end up treating the next data + * segment as empty, and we can avoid producing bogus output pixels by + * leaving the flag set. + */ + if (cinfo->unread_marker == 0) + entropy->insufficient_data = FALSE; + + return TRUE; +} + + +/* + * Decode and return nMCU's worth of Huffman-compressed differences. + * Each MCU is also disassembled and placed accordingly in diff_buf. + * + * MCU_col_num specifies the column of the first MCU being requested within + * the MCU-row. This tells us where to position the output row pointers in + * diff_buf. + * + * Returns the number of MCUs decoded. This may be less than nMCU if data + * source requested suspension. In that case no changes have been made to + * permanent state. (Exception: some output differences may already have + * been assigned. This is harmless for this module, since we'll just + * re-assign them on the next call.) + */ + +METHODDEF(JDIMENSION) +decode_mcus (j_decompress_ptr cinfo, JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, JDIMENSION MCU_col_num, JDIMENSION nMCU) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + lhuff_entropy_ptr entropy = (lhuff_entropy_ptr) losslsd->entropy_private; + unsigned int mcu_num; + int sampn, ci, yoffset, MCU_width, ptrn; + BITREAD_STATE_VARS; + + /* Set output pointer locations based on MCU_col_num */ + for (ptrn = 0; ptrn < entropy->num_output_ptrs; ptrn++) { + ci = entropy->output_ptr_info[ptrn].ci; + yoffset = entropy->output_ptr_info[ptrn].yoffset; + MCU_width = entropy->output_ptr_info[ptrn].MCU_width; + entropy->output_ptr[ptrn] = + diff_buf[ci][MCU_row_num + yoffset] + (MCU_col_num * MCU_width); + } + + /* + * If we've run out of data, zero out the buffers and return. + * By resetting the undifferencer, the output samples will be CENTERJSAMPLE. + * + * NB: We should find a way to do this without interacting with the + * undifferencer module directly. + */ + if (entropy->insufficient_data) { + for (ptrn = 0; ptrn < entropy->num_output_ptrs; ptrn++) + jzero_far((void FAR *) entropy->output_ptr[ptrn], + nMCU * entropy->output_ptr_info[ptrn].MCU_width * SIZEOF(JDIFF)); + + (*losslsd->predict_process_restart) (cinfo); + } + + else { + + /* Load up working state */ + BITREAD_LOAD_STATE(cinfo,entropy->bitstate); + + /* Outer loop handles the number of MCU requested */ + + for (mcu_num = 0; mcu_num < nMCU; mcu_num++) { + + /* Inner loop handles the samples in the MCU */ + for (sampn = 0; sampn < cinfo->data_units_in_MCU; sampn++) { + d_derived_tbl * dctbl = entropy->cur_tbls[sampn]; + register int s, r; + + /* Section H.2.2: decode the sample difference */ + HUFF_DECODE(s, br_state, dctbl, return mcu_num, label1); + if (s) { + if (s == 16) /* special case: always output 32768 */ + s = 32768; + else { /* normal case: fetch subsequent bits */ + CHECK_BIT_BUFFER(br_state, s, return mcu_num); + r = GET_BITS(s); + s = HUFF_EXTEND(r, s); + } + } + + /* Output the sample difference */ + *entropy->output_ptr[entropy->output_ptr_index[sampn]]++ = (JDIFF) s; + } + + /* Completed MCU, so update state */ + BITREAD_SAVE_STATE(cinfo,entropy->bitstate); + } + } + + return nMCU; +} + + +/* + * Module initialization routine for lossless Huffman entropy decoding. + */ + +GLOBAL(void) +jinit_lhuff_decoder (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + lhuff_entropy_ptr entropy; + int i; + + entropy = (lhuff_entropy_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(lhuff_entropy_decoder)); + losslsd->entropy_private = (void *) entropy; + losslsd->entropy_start_pass = start_pass_lhuff_decoder; + losslsd->entropy_process_restart = process_restart; + losslsd->entropy_decode_mcus = decode_mcus; + + /* Mark tables unallocated */ + for (i = 0; i < NUM_HUFF_TBLS; i++) { + entropy->derived_tbls[i] = NULL; + } +} + +#endif /* D_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jdlossls.c b/src/gdcmjpeg/jdlossls.c new file mode 100644 index 00000000..046cd3b7 --- /dev/null +++ b/src/gdcmjpeg/jdlossls.c @@ -0,0 +1,94 @@ +/* + * jdlossls.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the control logic for the lossless JPEG decompressor. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" + + +#ifdef D_LOSSLESS_SUPPORTED + +/* + * Compute output image dimensions and related values. + */ + +METHODDEF(void) +calc_output_dimensions (j_decompress_ptr cinfo) +{ + /* Hardwire it to "no scaling" */ + cinfo->output_width = cinfo->image_width; + cinfo->output_height = cinfo->image_height; + /* jdinput.c has already initialized codec_data_unit to 1, + * and has computed unscaled downsampled_width and downsampled_height. + */ +} + + +/* + * Initialize for an input processing pass. + */ + +METHODDEF(void) +start_input_pass (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + + (*losslsd->entropy_start_pass) (cinfo); + (*losslsd->predict_start_pass) (cinfo); + (*losslsd->scaler_start_pass) (cinfo); + (*losslsd->diff_start_input_pass) (cinfo); +} + + +/* + * Initialize the lossless decompression codec. + * This is called only once, during master selection. + */ + +GLOBAL(void) +jinit_lossless_d_codec(j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd; + boolean use_c_buffer; + + /* Create subobject in permanent pool */ + losslsd = (j_lossless_d_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(jpeg_lossless_d_codec)); + cinfo->codec = (struct jpeg_d_codec *) losslsd; + + /* Initialize sub-modules */ + /* Entropy decoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { + jinit_arith_decoder(cinfo); + } else { + jinit_lhuff_decoder(cinfo); + } + + /* Undifferencer */ + jinit_undifferencer(cinfo); + + /* Scaler */ + jinit_d_scaler(cinfo); + + use_c_buffer = cinfo->inputctl->has_multiple_scans || cinfo->buffered_image; + jinit_d_diff_controller(cinfo, use_c_buffer); + + /* Initialize method pointers. + * + * Note: consume_data, start_output_pass and decompress_data are + * assigned in jddiffct.c. + */ + losslsd->pub.calc_output_dimensions = calc_output_dimensions; + losslsd->pub.start_input_pass = start_input_pass; +} + +#endif /* D_LOSSLESS_SUPPORTED */ diff --git a/src/gdcmjpeg/jdlossy.c b/src/gdcmjpeg/jdlossy.c new file mode 100644 index 00000000..637714fa --- /dev/null +++ b/src/gdcmjpeg/jdlossy.c @@ -0,0 +1,228 @@ +/* + * jdlossy.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the control logic for the lossy JPEG decompressor. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" + + +/* + * Compute output image dimensions and related values. + */ + +METHODDEF(void) +calc_output_dimensions (j_decompress_ptr cinfo) +{ +#ifdef IDCT_SCALING_SUPPORTED + int ci; + jpeg_component_info *compptr; + + /* Compute actual output image dimensions and DCT scaling choices. */ + if (cinfo->scale_num * 8 <= cinfo->scale_denom) { + /* Provide 1/8 scaling */ + cinfo->output_width = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width, 8L); + cinfo->output_height = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, 8L); + cinfo->min_codec_data_unit = 1; + } else if (cinfo->scale_num * 4 <= cinfo->scale_denom) { + /* Provide 1/4 scaling */ + cinfo->output_width = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width, 4L); + cinfo->output_height = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, 4L); + cinfo->min_codec_data_unit = 2; + } else if (cinfo->scale_num * 2 <= cinfo->scale_denom) { + /* Provide 1/2 scaling */ + cinfo->output_width = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width, 2L); + cinfo->output_height = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height, 2L); + cinfo->min_codec_data_unit = 4; + } else { + /* Provide 1/1 scaling */ + cinfo->output_width = cinfo->image_width; + cinfo->output_height = cinfo->image_height; + cinfo->min_codec_data_unit = DCTSIZE; + } + /* In selecting the actual DCT scaling for each component, we try to + * scale up the chroma components via IDCT scaling rather than upsampling. + * This saves time if the upsampler gets to use 1:1 scaling. + * Note this code assumes that the supported DCT scalings are powers of 2. + */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + int ssize = cinfo->min_codec_data_unit; + while (ssize < DCTSIZE && + (compptr->h_samp_factor * ssize * 2 <= + cinfo->max_h_samp_factor * cinfo->min_codec_data_unit) && + (compptr->v_samp_factor * ssize * 2 <= + cinfo->max_v_samp_factor * cinfo->min_codec_data_unit)) { + ssize = ssize * 2; + } + compptr->codec_data_unit = ssize; + } + + /* Recompute downsampled dimensions of components; + * application needs to know these if using raw downsampled data. + */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Size in samples, after IDCT scaling */ + compptr->downsampled_width = (JDIMENSION) + jdiv_round_up((long) cinfo->image_width * + (long) (compptr->h_samp_factor * compptr->codec_data_unit), + (long) (cinfo->max_h_samp_factor * DCTSIZE)); + compptr->downsampled_height = (JDIMENSION) + jdiv_round_up((long) cinfo->image_height * + (long) (compptr->v_samp_factor * compptr->codec_data_unit), + (long) (cinfo->max_v_samp_factor * DCTSIZE)); + } + +#else /* !IDCT_SCALING_SUPPORTED */ + + /* Hardwire it to "no scaling" */ + cinfo->output_width = cinfo->image_width; + cinfo->output_height = cinfo->image_height; + /* jdinput.c has already initialized codec_data_unit to DCTSIZE, + * and has computed unscaled downsampled_width and downsampled_height. + */ + +#endif /* IDCT_SCALING_SUPPORTED */ +} + + +/* + * Save away a copy of the Q-table referenced by each component present + * in the current scan, unless already saved during a prior scan. + * + * In a multiple-scan JPEG file, the encoder could assign different components + * the same Q-table slot number, but change table definitions between scans + * so that each component uses a different Q-table. (The IJG encoder is not + * currently capable of doing this, but other encoders might.) Since we want + * to be able to dequantize all the components at the end of the file, this + * means that we have to save away the table actually used for each component. + * We do this by copying the table at the start of the first scan containing + * the component. + * The JPEG spec prohibits the encoder from changing the contents of a Q-table + * slot between scans of a component using that slot. If the encoder does so + * anyway, this decoder will simply use the Q-table values that were current + * at the start of the first scan for the component. + * + * The decompressor output side looks only at the saved quant tables, + * not at the current Q-table slots. + */ + +LOCAL(void) +latch_quant_tables (j_decompress_ptr cinfo) +{ + int ci, qtblno; + jpeg_component_info *compptr; + JQUANT_TBL * qtbl; + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + /* No work if we already saved Q-table for this component */ + if (compptr->quant_table != NULL) + continue; + /* Make sure specified quantization table is present */ + qtblno = compptr->quant_tbl_no; + if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS || + cinfo->quant_tbl_ptrs[qtblno] == NULL) + ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno); + /* OK, save away the quantization table */ + qtbl = (JQUANT_TBL *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(JQUANT_TBL)); + MEMCOPY(qtbl, cinfo->quant_tbl_ptrs[qtblno], SIZEOF(JQUANT_TBL)); + compptr->quant_table = qtbl; + } +} + + +/* + * Initialize for an input processing pass. + */ + +METHODDEF(void) +start_input_pass (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + + latch_quant_tables(cinfo); + (*lossyd->entropy_start_pass) (cinfo); + (*lossyd->coef_start_input_pass) (cinfo); +} + + +/* + * Initialize for an output processing pass. + */ + +METHODDEF(void) +start_output_pass (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + + (*lossyd->idct_start_pass) (cinfo); + (*lossyd->coef_start_output_pass) (cinfo); +} + +/* + * Initialize the lossy decompression codec. + * This is called only once, during master selection. + */ + +GLOBAL(void) +jinit_lossy_d_codec (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd; + boolean use_c_buffer; + + /* Create subobject in permanent pool */ + lossyd = (j_lossy_d_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(jpeg_lossy_d_codec)); + cinfo->codec = (struct jpeg_d_codec *) lossyd; + + /* Initialize sub-modules */ + + /* Inverse DCT */ + jinit_inverse_dct(cinfo); + /* Entropy decoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { + jinit_arith_decoder(cinfo); + } else { + if (cinfo->process == JPROC_PROGRESSIVE) { +#ifdef D_PROGRESSIVE_SUPPORTED + jinit_phuff_decoder(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else + jinit_shuff_decoder(cinfo); + } + + use_c_buffer = cinfo->inputctl->has_multiple_scans || cinfo->buffered_image; + jinit_d_coef_controller(cinfo, use_c_buffer); + + /* Initialize method pointers. + * + * Note: consume_data and decompress_data are assigned in jdcoefct.c. + */ + lossyd->pub.calc_output_dimensions = calc_output_dimensions; + lossyd->pub.start_input_pass = start_input_pass; + lossyd->pub.start_output_pass = start_output_pass; +} + + + + diff --git a/src/gdcmjpeg/jdmainct.c b/src/gdcmjpeg/jdmainct.c new file mode 100644 index 00000000..43cb09b7 --- /dev/null +++ b/src/gdcmjpeg/jdmainct.c @@ -0,0 +1,512 @@ +/* + * jdmainct.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the main buffer controller for decompression. + * The main buffer lies between the JPEG decompressor proper and the + * post-processor; it holds downsampled data in the JPEG colorspace. + * + * Note that this code is bypassed in raw-data mode, since the application + * supplies the equivalent of the main buffer in that case. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * In the current system design, the main buffer need never be a full-image + * buffer; any full-height buffers will be found inside the coefficient or + * postprocessing controllers. Nonetheless, the main controller is not + * trivial. Its responsibility is to provide context rows for upsampling/ + * rescaling, and doing this in an efficient fashion is a bit tricky. + * + * Postprocessor input data is counted in "row groups". A row group + * is defined to be (v_samp_factor * codec_data_unit / min_codec_data_unit) + * sample rows of each component. (We require codec_data_unit values to be + * chosen such that these numbers are integers. In practice codec_data_unit + * values will likely be powers of two, so we actually have the stronger + * condition that codec_data_unit / min_codec_data_unit is an integer.) + * Upsampling will typically produce max_v_samp_factor pixel rows from each + * row group (times any additional scale factor that the upsampler is + * applying). + * + * The decompression codec will deliver data to us one iMCU row at a time; + * each iMCU row contains v_samp_factor * codec_data_unit sample rows, or + * exactly min_codec_data_unit row groups. (This amount of data corresponds + * to one row of MCUs when the image is fully interleaved.) Note that the + * number of sample rows varies across components, but the number of row + * groups does not. Some garbage sample rows may be included in the last iMCU + * row at the bottom of the image. + * + * Depending on the vertical scaling algorithm used, the upsampler may need + * access to the sample row(s) above and below its current input row group. + * The upsampler is required to set need_context_rows TRUE at global selection + * time if so. When need_context_rows is FALSE, this controller can simply + * obtain one iMCU row at a time from the coefficient controller and dole it + * out as row groups to the postprocessor. + * + * When need_context_rows is TRUE, this controller guarantees that the buffer + * passed to postprocessing contains at least one row group's worth of samples + * above and below the row group(s) being processed. Note that the context + * rows "above" the first passed row group appear at negative row offsets in + * the passed buffer. At the top and bottom of the image, the required + * context rows are manufactured by duplicating the first or last real sample + * row; this avoids having special cases in the upsampling inner loops. + * + * The amount of context is fixed at one row group just because that's a + * convenient number for this controller to work with. The existing + * upsamplers really only need one sample row of context. An upsampler + * supporting arbitrary output rescaling might wish for more than one row + * group of context when shrinking the image; tough, we don't handle that. + * (This is justified by the assumption that downsizing will be handled mostly + * by adjusting the codec_data_unit values, so that the actual scale factor at + * the upsample step needn't be much less than one.) + * + * To provide the desired context, we have to retain the last two row groups + * of one iMCU row while reading in the next iMCU row. (The last row group + * can't be processed until we have another row group for its below-context, + * and so we have to save the next-to-last group too for its above-context.) + * We could do this most simply by copying data around in our buffer, but + * that'd be very slow. We can avoid copying any data by creating a rather + * strange pointer structure. Here's how it works. We allocate a workspace + * consisting of M+2 row groups (where M = min_codec_data_unit is the number + * of row groups per iMCU row). We create two sets of redundant pointers to + * the workspace. Labeling the physical row groups 0 to M+1, the synthesized + * pointer lists look like this: + * M+1 M-1 + * master pointer --> 0 master pointer --> 0 + * 1 1 + * ... ... + * M-3 M-3 + * M-2 M + * M-1 M+1 + * M M-2 + * M+1 M-1 + * 0 0 + * We read alternate iMCU rows using each master pointer; thus the last two + * row groups of the previous iMCU row remain un-overwritten in the workspace. + * The pointer lists are set up so that the required context rows appear to + * be adjacent to the proper places when we pass the pointer lists to the + * upsampler. + * + * The above pictures describe the normal state of the pointer lists. + * At top and bottom of the image, we diddle the pointer lists to duplicate + * the first or last sample row as necessary (this is cheaper than copying + * sample rows around). + * + * This scheme breaks down if M < 2, ie, min_codec_data_unit is 1. In that + * situation each iMCU row provides only one row group so the buffering logic + * must be different (eg, we must read two iMCU rows before we can emit the + * first row group). For now, we simply do not support providing context + * rows when min_codec_data_unit is 1. That combination seems unlikely to + * be worth providing --- if someone wants a 1/8th-size preview, they probably + * want it quick and dirty, so a context-free upsampler is sufficient. + */ + + +/* Private buffer controller object */ + +typedef struct { + struct jpeg_d_main_controller pub; /* public fields */ + + /* Pointer to allocated workspace (M or M+2 row groups). */ + JSAMPARRAY buffer[MAX_COMPONENTS]; + + boolean buffer_full; /* Have we gotten an iMCU row from decoder? */ + JDIMENSION rowgroup_ctr; /* counts row groups output to postprocessor */ + + /* Remaining fields are only used in the context case. */ + + /* These are the master pointers to the funny-order pointer lists. */ + JSAMPIMAGE xbuffer[2]; /* pointers to weird pointer lists */ + + int whichptr; /* indicates which pointer set is now in use */ + int context_state; /* process_data state machine status */ + JDIMENSION rowgroups_avail; /* row groups available to postprocessor */ + JDIMENSION iMCU_row_ctr; /* counts iMCU rows to detect image top/bot */ +} my_main_controller; + +typedef my_main_controller * my_main_ptr; + +/* context_state values: */ +#define CTX_PREPARE_FOR_IMCU 0 /* need to prepare for MCU row */ +#define CTX_PROCESS_IMCU 1 /* feeding iMCU to postprocessor */ +#define CTX_POSTPONED_ROW 2 /* feeding postponed row group */ + + +/* Forward declarations */ +METHODDEF(void) process_data_simple_main + JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); +METHODDEF(void) process_data_context_main + JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); +#ifdef QUANT_2PASS_SUPPORTED +METHODDEF(void) process_data_crank_post + JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); +#endif + + +LOCAL(void) +alloc_funny_pointers (j_decompress_ptr cinfo) +/* Allocate space for the funny pointer lists. + * This is done only once, not once per pass. + */ +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + int ci, rgroup; + int M = cinfo->min_codec_data_unit; + jpeg_component_info *compptr; + JSAMPARRAY xbuf; + + /* Get top-level space for component array pointers. + * We alloc both arrays with one call to save a few cycles. + */ + mainPtr->xbuffer[0] = (JSAMPIMAGE) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + cinfo->num_components * 2 * SIZEOF(JSAMPARRAY)); + mainPtr->xbuffer[1] = mainPtr->xbuffer[0] + cinfo->num_components; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + rgroup = (compptr->v_samp_factor * compptr->codec_data_unit) / + cinfo->min_codec_data_unit; /* height of a row group of component */ + /* Get space for pointer lists --- M+4 row groups in each list. + * We alloc both pointer lists with one call to save a few cycles. + */ + xbuf = (JSAMPARRAY) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + 2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW)); + xbuf += rgroup; /* want one row group at negative offsets */ + mainPtr->xbuffer[0][ci] = xbuf; + xbuf += rgroup * (M + 4); + mainPtr->xbuffer[1][ci] = xbuf; + } +} + + +LOCAL(void) +make_funny_pointers (j_decompress_ptr cinfo) +/* Create the funny pointer lists discussed in the comments above. + * The actual workspace is already allocated (in mainPtr->buffer), + * and the space for the pointer lists is allocated too. + * This routine just fills in the curiously ordered lists. + * This will be repeated at the beginning of each pass. + */ +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + int ci, i, rgroup; + int M = cinfo->min_codec_data_unit; + jpeg_component_info *compptr; + JSAMPARRAY buf, xbuf0, xbuf1; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + rgroup = (compptr->v_samp_factor * compptr->codec_data_unit) / + cinfo->min_codec_data_unit; /* height of a row group of component */ + xbuf0 = mainPtr->xbuffer[0][ci]; + xbuf1 = mainPtr->xbuffer[1][ci]; + /* First copy the workspace pointers as-is */ + buf = mainPtr->buffer[ci]; + for (i = 0; i < rgroup * (M + 2); i++) { + xbuf0[i] = xbuf1[i] = buf[i]; + } + /* In the second list, put the last four row groups in swapped order */ + for (i = 0; i < rgroup * 2; i++) { + xbuf1[rgroup*(M-2) + i] = buf[rgroup*M + i]; + xbuf1[rgroup*M + i] = buf[rgroup*(M-2) + i]; + } + /* The wraparound pointers at top and bottom will be filled later + * (see set_wraparound_pointers, below). Initially we want the "above" + * pointers to duplicate the first actual data line. This only needs + * to happen in xbuffer[0]. + */ + for (i = 0; i < rgroup; i++) { + xbuf0[i - rgroup] = xbuf0[0]; + } + } +} + + +LOCAL(void) +set_wraparound_pointers (j_decompress_ptr cinfo) +/* Set up the "wraparound" pointers at top and bottom of the pointer lists. + * This changes the pointer list state from top-of-image to the normal state. + */ +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + int ci, i, rgroup; + int M = cinfo->min_codec_data_unit; + jpeg_component_info *compptr; + JSAMPARRAY xbuf0, xbuf1; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + rgroup = (compptr->v_samp_factor * compptr->codec_data_unit) / + cinfo->min_codec_data_unit; /* height of a row group of component */ + xbuf0 = mainPtr->xbuffer[0][ci]; + xbuf1 = mainPtr->xbuffer[1][ci]; + for (i = 0; i < rgroup; i++) { + xbuf0[i - rgroup] = xbuf0[rgroup*(M+1) + i]; + xbuf1[i - rgroup] = xbuf1[rgroup*(M+1) + i]; + xbuf0[rgroup*(M+2) + i] = xbuf0[i]; + xbuf1[rgroup*(M+2) + i] = xbuf1[i]; + } + } +} + + +LOCAL(void) +set_bottom_pointers (j_decompress_ptr cinfo) +/* Change the pointer lists to duplicate the last sample row at the bottom + * of the image. whichptr indicates which xbuffer holds the final iMCU row. + * Also sets rowgroups_avail to indicate number of nondummy row groups in row. + */ +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + int ci, i, rgroup, iMCUheight, rows_left; + jpeg_component_info *compptr; + JSAMPARRAY xbuf; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Count sample rows in one iMCU row and in one row group */ + iMCUheight = compptr->v_samp_factor * compptr->codec_data_unit; + rgroup = iMCUheight / cinfo->min_codec_data_unit; + /* Count nondummy sample rows remaining for this component */ + rows_left = (int) (compptr->downsampled_height % (JDIMENSION) iMCUheight); + if (rows_left == 0) rows_left = iMCUheight; + /* Count nondummy row groups. Should get same answer for each component, + * so we need only do it once. + */ + if (ci == 0) { + mainPtr->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1); + } + /* Duplicate the last real sample row rgroup*2 times; this pads out the + * last partial rowgroup and ensures at least one full rowgroup of context. + */ + xbuf = mainPtr->xbuffer[mainPtr->whichptr][ci]; + for (i = 0; i < rgroup * 2; i++) { + xbuf[rows_left + i] = xbuf[rows_left-1]; + } + } +} + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode) +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + + switch (pass_mode) { + case JBUF_PASS_THRU: + if (cinfo->upsample->need_context_rows) { + mainPtr->pub.process_data = process_data_context_main; + make_funny_pointers(cinfo); /* Create the xbuffer[] lists */ + mainPtr->whichptr = 0; /* Read first iMCU row into xbuffer[0] */ + mainPtr->context_state = CTX_PREPARE_FOR_IMCU; + mainPtr->iMCU_row_ctr = 0; + } else { + /* Simple case with no context needed */ + mainPtr->pub.process_data = process_data_simple_main; + } + mainPtr->buffer_full = FALSE; /* Mark buffer empty */ + mainPtr->rowgroup_ctr = 0; + break; +#ifdef QUANT_2PASS_SUPPORTED + case JBUF_CRANK_DEST: + /* For last pass of 2-pass quantization, just crank the postprocessor */ + mainPtr->pub.process_data = process_data_crank_post; + break; +#endif + default: + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + break; + } +} + + +/* + * Process some data. + * This handles the simple case where no context is required. + */ + +METHODDEF(void) +process_data_simple_main (j_decompress_ptr cinfo, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + JDIMENSION rowgroups_avail; + + /* Read input data if we haven't filled the main buffer yet */ + if (! mainPtr->buffer_full) { + if (! (*cinfo->codec->decompress_data) (cinfo, mainPtr->buffer)) + return; /* suspension forced, can do nothing more */ + mainPtr->buffer_full = TRUE; /* OK, we have an iMCU row to work with */ + } + + /* There are always min_codec_data_unit row groups in an iMCU row. */ + rowgroups_avail = (JDIMENSION) cinfo->min_codec_data_unit; + /* Note: at the bottom of the image, we may pass extra garbage row groups + * to the postprocessor. The postprocessor has to check for bottom + * of image anyway (at row resolution), so no point in us doing it too. + */ + + /* Feed the postprocessor */ + (*cinfo->post->post_process_data) (cinfo, mainPtr->buffer, + &mainPtr->rowgroup_ctr, rowgroups_avail, + output_buf, out_row_ctr, out_rows_avail); + + /* Has postprocessor consumed all the data yet? If so, mark buffer empty */ + if (mainPtr->rowgroup_ctr >= rowgroups_avail) { + mainPtr->buffer_full = FALSE; + mainPtr->rowgroup_ctr = 0; + } +} + + +/* + * Process some data. + * This handles the case where context rows must be provided. + */ + +METHODDEF(void) +process_data_context_main (j_decompress_ptr cinfo, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + my_main_ptr mainPtr = (my_main_ptr) cinfo->main; + + /* Read input data if we haven't filled the main buffer yet */ + if (! mainPtr->buffer_full) { + if (! (*cinfo->codec->decompress_data) (cinfo, + mainPtr->xbuffer[mainPtr->whichptr])) + return; /* suspension forced, can do nothing more */ + mainPtr->buffer_full = TRUE; /* OK, we have an iMCU row to work with */ + mainPtr->iMCU_row_ctr++; /* count rows received */ + } + + /* Postprocessor typically will not swallow all the input data it is handed + * in one call (due to filling the output buffer first). Must be prepared + * to exit and restart. This switch lets us keep track of how far we got. + * Note that each case falls through to the next on successful completion. + */ + switch (mainPtr->context_state) { + case CTX_POSTPONED_ROW: + /* Call postprocessor using previously set pointers for postponed row */ + (*cinfo->post->post_process_data) (cinfo, mainPtr->xbuffer[mainPtr->whichptr], + &mainPtr->rowgroup_ctr, mainPtr->rowgroups_avail, + output_buf, out_row_ctr, out_rows_avail); + if (mainPtr->rowgroup_ctr < mainPtr->rowgroups_avail) + return; /* Need to suspend */ + mainPtr->context_state = CTX_PREPARE_FOR_IMCU; + if (*out_row_ctr >= out_rows_avail) + return; /* Postprocessor exactly filled output buf */ + /*FALLTHROUGH*/ + case CTX_PREPARE_FOR_IMCU: + /* Prepare to process first M-1 row groups of this iMCU row */ + mainPtr->rowgroup_ctr = 0; + mainPtr->rowgroups_avail = (JDIMENSION) (cinfo->min_codec_data_unit - 1); + /* Check for bottom of image: if so, tweak pointers to "duplicate" + * the last sample row, and adjust rowgroups_avail to ignore padding rows. + */ + if (mainPtr->iMCU_row_ctr == cinfo->total_iMCU_rows) + set_bottom_pointers(cinfo); + mainPtr->context_state = CTX_PROCESS_IMCU; + /*FALLTHROUGH*/ + case CTX_PROCESS_IMCU: + /* Call postprocessor using previously set pointers */ + (*cinfo->post->post_process_data) (cinfo, mainPtr->xbuffer[mainPtr->whichptr], + &mainPtr->rowgroup_ctr, mainPtr->rowgroups_avail, + output_buf, out_row_ctr, out_rows_avail); + if (mainPtr->rowgroup_ctr < mainPtr->rowgroups_avail) + return; /* Need to suspend */ + /* After the first iMCU, change wraparound pointers to normal state */ + if (mainPtr->iMCU_row_ctr == 1) + set_wraparound_pointers(cinfo); + /* Prepare to load new iMCU row using other xbuffer list */ + mainPtr->whichptr ^= 1; /* 0=>1 or 1=>0 */ + mainPtr->buffer_full = FALSE; + /* Still need to process last row group of this iMCU row, */ + /* which is saved at index M+1 of the other xbuffer */ + mainPtr->rowgroup_ctr = (JDIMENSION) (cinfo->min_codec_data_unit + 1); + mainPtr->rowgroups_avail = (JDIMENSION) (cinfo->min_codec_data_unit + 2); + mainPtr->context_state = CTX_POSTPONED_ROW; + } +} + + +/* + * Process some data. + * Final pass of two-pass quantization: just call the postprocessor. + * Source data will be the postprocessor controller's internal buffer. + */ + +#ifdef QUANT_2PASS_SUPPORTED + +METHODDEF(void) +process_data_crank_post (j_decompress_ptr cinfo, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + (*cinfo->post->post_process_data) (cinfo, (JSAMPIMAGE) NULL, + (JDIMENSION *) NULL, (JDIMENSION) 0, + output_buf, out_row_ctr, out_rows_avail); +} + +#endif /* QUANT_2PASS_SUPPORTED */ + + +/* + * Initialize main buffer controller. + */ + +GLOBAL(void) +jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer) +{ + my_main_ptr mainPtr; + int ci, rgroup, ngroups; + jpeg_component_info *compptr; + + mainPtr = (my_main_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_main_controller)); + cinfo->main = (struct jpeg_d_main_controller *) mainPtr; + mainPtr->pub.start_pass = start_pass_main; + + if (need_full_buffer) /* shouldn't happen */ + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + + /* Allocate the workspace. + * ngroups is the number of row groups we need. + */ + if (cinfo->upsample->need_context_rows) { + if (cinfo->min_codec_data_unit < 2) /* unsupported, see comments above */ + ERREXIT(cinfo, JERR_NOTIMPL); + alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */ + ngroups = cinfo->min_codec_data_unit + 2; + } else { + ngroups = cinfo->min_codec_data_unit; + } + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + rgroup = (compptr->v_samp_factor * compptr->codec_data_unit) / + cinfo->min_codec_data_unit; /* height of a row group of component */ + mainPtr->buffer[ci] = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + compptr->width_in_data_units * compptr->codec_data_unit, + (JDIMENSION) (rgroup * ngroups)); + } +} diff --git a/src/gdcmjpeg/jdmarker.c b/src/gdcmjpeg/jdmarker.c new file mode 100644 index 00000000..e280621b --- /dev/null +++ b/src/gdcmjpeg/jdmarker.c @@ -0,0 +1,1370 @@ +/* + * jdmarker.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains routines to decode JPEG datastream markers. + * Most of the complexity arises from our desire to support input + * suspension: if not all of the data for a marker is available, + * we must exit back to the application. On resumption, we reprocess + * the marker. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +typedef enum { /* JPEG marker codes */ + M_SOF0 = 0xc0, + M_SOF1 = 0xc1, + M_SOF2 = 0xc2, + M_SOF3 = 0xc3, + + M_SOF5 = 0xc5, + M_SOF6 = 0xc6, + M_SOF7 = 0xc7, + + M_JPG = 0xc8, + M_SOF9 = 0xc9, + M_SOF10 = 0xca, + M_SOF11 = 0xcb, + + M_SOF13 = 0xcd, + M_SOF14 = 0xce, + M_SOF15 = 0xcf, + + M_DHT = 0xc4, + + M_DAC = 0xcc, + + M_RST0 = 0xd0, + M_RST1 = 0xd1, + M_RST2 = 0xd2, + M_RST3 = 0xd3, + M_RST4 = 0xd4, + M_RST5 = 0xd5, + M_RST6 = 0xd6, + M_RST7 = 0xd7, + + M_SOI = 0xd8, + M_EOI = 0xd9, + M_SOS = 0xda, + M_DQT = 0xdb, + M_DNL = 0xdc, + M_DRI = 0xdd, + M_DHP = 0xde, + M_EXP = 0xdf, + + M_APP0 = 0xe0, + M_APP1 = 0xe1, + M_APP2 = 0xe2, + M_APP3 = 0xe3, + M_APP4 = 0xe4, + M_APP5 = 0xe5, + M_APP6 = 0xe6, + M_APP7 = 0xe7, + M_APP8 = 0xe8, + M_APP9 = 0xe9, + M_APP10 = 0xea, + M_APP11 = 0xeb, + M_APP12 = 0xec, + M_APP13 = 0xed, + M_APP14 = 0xee, + M_APP15 = 0xef, + + M_JPG0 = 0xf0, + M_JPG13 = 0xfd, + M_COM = 0xfe, + + M_TEM = 0x01, + + M_ERROR = 0x100 +} JPEG_MARKER; + + +/* Private state */ + +typedef struct { + struct jpeg_marker_reader pub; /* public fields */ + + /* Application-overridable marker processing methods */ + jpeg_marker_parser_method process_COM; + jpeg_marker_parser_method process_APPn[16]; + + /* Limit on marker data length to save for each marker type */ + unsigned int length_limit_COM; + unsigned int length_limit_APPn[16]; + + /* Status of COM/APPn marker saving */ + jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */ + unsigned int bytes_read; /* data bytes read so far in marker */ + /* Note: cur_marker is not linked into marker_list until it's all read. */ +} my_marker_reader; + +typedef my_marker_reader * my_marker_ptr; + + +/* + * Macros for fetching data from the data source module. + * + * At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect + * the current restart point; we update them only when we have reached a + * suitable place to restart if a suspension occurs. + */ + +/* Declare and initialize local copies of input pointer/count */ +#define INPUT_VARS(cinfo) \ + struct jpeg_source_mgr * datasrc = (cinfo)->src; \ + const JOCTET * next_input_byte = datasrc->next_input_byte; \ + size_t bytes_in_buffer = datasrc->bytes_in_buffer + +/* Unload the local copies --- do this only at a restart boundary */ +#define INPUT_SYNC(cinfo) \ + ( datasrc->next_input_byte = next_input_byte, \ + datasrc->bytes_in_buffer = bytes_in_buffer ) + +/* Reload the local copies --- used only in MAKE_BYTE_AVAIL */ +#define INPUT_RELOAD(cinfo) \ + ( next_input_byte = datasrc->next_input_byte, \ + bytes_in_buffer = datasrc->bytes_in_buffer ) + +/* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available. + * Note we do *not* do INPUT_SYNC before calling fill_input_buffer, + * but we must reload the local copies after a successful fill. + */ +#define MAKE_BYTE_AVAIL(cinfo,action) \ + if (bytes_in_buffer == 0) { \ + if (! (*datasrc->fill_input_buffer) (cinfo)) \ + { action; } \ + INPUT_RELOAD(cinfo); \ + } + +/* Read a byte into variable V. + * If must suspend, take the specified action (typically "return FALSE"). + */ +#define INPUT_BYTE(cinfo,V,action) \ + MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ + bytes_in_buffer--; \ + V = GETJOCTET(*next_input_byte++); ) + +/* As above, but read two bytes interpreted as an unsigned 16-bit integer. + * V should be declared unsigned int or perhaps INT32. + */ +#define INPUT_2BYTES(cinfo,V,action) \ + MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ + bytes_in_buffer--; \ + V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \ + MAKE_BYTE_AVAIL(cinfo,action); \ + bytes_in_buffer--; \ + V += GETJOCTET(*next_input_byte++); ) + + +/* + * Routines to process JPEG markers. + * + * Entry condition: JPEG marker itself has been read and its code saved + * in cinfo->unread_marker; input restart point is just after the marker. + * + * Exit: if return TRUE, have read and processed any parameters, and have + * updated the restart point to point after the parameters. + * If return FALSE, was forced to suspend before reaching end of + * marker parameters; restart point has not been moved. Same routine + * will be called again after application supplies more input data. + * + * This approach to suspension assumes that all of a marker's parameters + * can fit into a single input bufferload. This should hold for "normal" + * markers. Some COM/APPn markers might have large parameter segments + * that might not fit. If we are simply dropping such a marker, we use + * skip_input_data to get past it, and thereby put the problem on the + * source manager's shoulders. If we are saving the marker's contents + * into memory, we use a slightly different convention: when forced to + * suspend, the marker processor updates the restart point to the end of + * what it's consumed (ie, the end of the buffer) before returning FALSE. + * On resumption, cinfo->unread_marker still contains the marker code, + * but the data source will point to the next chunk of marker data. + * The marker processor must retain internal state to deal with this. + * + * Note that we don't bother to avoid duplicate trace messages if a + * suspension occurs within marker parameters. Other side effects + * require more care. + */ + + +LOCAL(boolean) +get_soi (j_decompress_ptr cinfo) +/* Process an SOI marker */ +{ + int i; + + TRACEMS(cinfo, 1, JTRC_SOI); + + if (cinfo->marker->saw_SOI) + ERREXIT(cinfo, JERR_SOI_DUPLICATE); + + /* Reset all parameters that are defined to be reset by SOI */ + + for (i = 0; i < NUM_ARITH_TBLS; i++) { + cinfo->arith_dc_L[i] = 0; + cinfo->arith_dc_U[i] = 1; + cinfo->arith_ac_K[i] = 5; + } + cinfo->restart_interval = 0; + + /* Set initial assumptions for colorspace etc */ + + cinfo->jpeg_color_space = JCS_UNKNOWN; + cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */ + + cinfo->saw_JFIF_marker = FALSE; + cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */ + cinfo->JFIF_minor_version = 1; + cinfo->density_unit = 0; + cinfo->X_density = 1; + cinfo->Y_density = 1; + cinfo->saw_Adobe_marker = FALSE; + cinfo->Adobe_transform = 0; + + cinfo->marker->saw_SOI = TRUE; + + return TRUE; +} + + +LOCAL(boolean) +get_sof (j_decompress_ptr cinfo, J_CODEC_PROCESS process, boolean is_arith, + int data_unit) +/* Process a SOFn marker */ +{ + INT32 length; + int c, ci; + jpeg_component_info * compptr; + INPUT_VARS(cinfo); + + cinfo->data_unit = data_unit; + cinfo->process = process; + cinfo->arith_code = is_arith; + + INPUT_2BYTES(cinfo, length, return FALSE); + + INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE); + INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE); + INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE); + INPUT_BYTE(cinfo, cinfo->num_components, return FALSE); + + length -= 8; + + TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker, + (int) cinfo->image_width, (int) cinfo->image_height, + cinfo->num_components); + + if (cinfo->marker->saw_SOF) + ERREXIT(cinfo, JERR_SOF_DUPLICATE); + + /* We don't support files in which the image height is initially specified */ + /* as 0 and is later redefined by DNL. As long as we have to check that, */ + /* might as well have a general sanity check. */ + if (cinfo->image_height <= 0 || cinfo->image_width <= 0 + || cinfo->num_components <= 0) + ERREXIT(cinfo, JERR_EMPTY_IMAGE); + + if (length != (cinfo->num_components * 3)) + ERREXIT(cinfo, JERR_BAD_LENGTH); + + if (cinfo->comp_info == NULL) /* do only once, even if suspend */ + cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + cinfo->num_components * SIZEOF(jpeg_component_info)); + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + compptr->component_index = ci; + INPUT_BYTE(cinfo, compptr->component_id, return FALSE); + INPUT_BYTE(cinfo, c, return FALSE); + compptr->h_samp_factor = (c >> 4) & 15; + compptr->v_samp_factor = (c ) & 15; + INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE); + + TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT, + compptr->component_id, compptr->h_samp_factor, + compptr->v_samp_factor, compptr->quant_tbl_no); + } + + cinfo->marker->saw_SOF = TRUE; + + INPUT_SYNC(cinfo); + return TRUE; +} + + +LOCAL(boolean) +get_sos (j_decompress_ptr cinfo) +/* Process a SOS marker */ +{ + INT32 length; + int i, ci, n, c, cc; + jpeg_component_info * compptr; + INPUT_VARS(cinfo); + + if (! cinfo->marker->saw_SOF) + ERREXIT(cinfo, JERR_SOS_NO_SOF); + + INPUT_2BYTES(cinfo, length, return FALSE); + + INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */ + + TRACEMS1(cinfo, 1, JTRC_SOS, n); + + if (length != (n * 2 + 6) || n < 1 || n > MAX_COMPS_IN_SCAN) + ERREXIT(cinfo, JERR_BAD_LENGTH); + + cinfo->comps_in_scan = n; + + /* Collect the component-spec parameters */ + + for (i = 0; i < n; i++) { + INPUT_BYTE(cinfo, cc, return FALSE); + INPUT_BYTE(cinfo, c, return FALSE); + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + if (cc == compptr->component_id) + goto id_found; + } + + ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc); + + id_found: + + cinfo->cur_comp_info[i] = compptr; + compptr->dc_tbl_no = (c >> 4) & 15; + compptr->ac_tbl_no = (c ) & 15; + + TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc, + compptr->dc_tbl_no, compptr->ac_tbl_no); + } + + /* Collect the additional scan parameters Ss, Se, Ah/Al. */ + INPUT_BYTE(cinfo, c, return FALSE); + cinfo->Ss = c; + INPUT_BYTE(cinfo, c, return FALSE); + cinfo->Se = c; + INPUT_BYTE(cinfo, c, return FALSE); + cinfo->Ah = (c >> 4) & 15; + cinfo->Al = (c ) & 15; + + TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se, + cinfo->Ah, cinfo->Al); + + /* Prepare to scan data & restart markers */ + cinfo->marker->next_restart_num = 0; + + /* Count another SOS marker */ + cinfo->input_scan_number++; + + INPUT_SYNC(cinfo); + return TRUE; +} + + +#ifdef D_ARITH_CODING_SUPPORTED + +LOCAL(boolean) +get_dac (j_decompress_ptr cinfo) +/* Process a DAC marker */ +{ + INT32 length; + int index, val; + INPUT_VARS(cinfo); + + INPUT_2BYTES(cinfo, length, return FALSE); + length -= 2; + + while (length > 0) { + INPUT_BYTE(cinfo, index, return FALSE); + INPUT_BYTE(cinfo, val, return FALSE); + + length -= 2; + + TRACEMS2(cinfo, 1, JTRC_DAC, index, val); + + if (index < 0 || index >= (2*NUM_ARITH_TBLS)) + ERREXIT1(cinfo, JERR_DAC_INDEX, index); + + if (index >= NUM_ARITH_TBLS) { /* define AC table */ + cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val; + } else { /* define DC table */ + cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F); + cinfo->arith_dc_U[index] = (UINT8) (val >> 4); + if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index]) + ERREXIT1(cinfo, JERR_DAC_VALUE, val); + } + } + + if (length != 0) + ERREXIT(cinfo, JERR_BAD_LENGTH); + + INPUT_SYNC(cinfo); + return TRUE; +} + +#else /* ! D_ARITH_CODING_SUPPORTED */ + +#define get_dac(cinfo) skip_variable(cinfo) + +#endif /* D_ARITH_CODING_SUPPORTED */ + + +LOCAL(boolean) +get_dht (j_decompress_ptr cinfo) +/* Process a DHT marker */ +{ + INT32 length; + UINT8 bits[17]; + UINT8 huffval[256]; + int i, index, count; + JHUFF_TBL **htblptr; + INPUT_VARS(cinfo); + + INPUT_2BYTES(cinfo, length, return FALSE); + length -= 2; + + while (length > 16) { + INPUT_BYTE(cinfo, index, return FALSE); + + TRACEMS1(cinfo, 1, JTRC_DHT, index); + + bits[0] = 0; + count = 0; + for (i = 1; i <= 16; i++) { + INPUT_BYTE(cinfo, bits[i], return FALSE); + count += bits[i]; + } + + length -= 1 + 16; + + TRACEMS8(cinfo, 2, JTRC_HUFFBITS, + bits[1], bits[2], bits[3], bits[4], + bits[5], bits[6], bits[7], bits[8]); + TRACEMS8(cinfo, 2, JTRC_HUFFBITS, + bits[9], bits[10], bits[11], bits[12], + bits[13], bits[14], bits[15], bits[16]); + + /* Here we just do minimal validation of the counts to avoid walking + * off the end of our table space. jdhuff.c will check more carefully. + */ + if (count > 256 || ((INT32) count) > length) + ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); + + for (i = 0; i < count; i++) + INPUT_BYTE(cinfo, huffval[i], return FALSE); + + length -= count; + + if (index & 0x10) { /* AC table definition */ + index -= 0x10; + htblptr = &cinfo->ac_huff_tbl_ptrs[index]; + } else { /* DC table definition */ + htblptr = &cinfo->dc_huff_tbl_ptrs[index]; + } + + if (index < 0 || index >= NUM_HUFF_TBLS) + ERREXIT1(cinfo, JERR_DHT_INDEX, index); + + if (*htblptr == NULL) + *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); + + MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits)); + MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval)); + } + + if (length != 0) + ERREXIT(cinfo, JERR_BAD_LENGTH); + + INPUT_SYNC(cinfo); + return TRUE; +} + + +LOCAL(boolean) +get_dqt (j_decompress_ptr cinfo) +/* Process a DQT marker */ +{ + INT32 length; + int n, i, prec; + unsigned int tmp; + JQUANT_TBL *quant_ptr; + INPUT_VARS(cinfo); + + INPUT_2BYTES(cinfo, length, return FALSE); + length -= 2; + + while (length > 0) { + INPUT_BYTE(cinfo, n, return FALSE); + prec = n >> 4; + n &= 0x0F; + + TRACEMS2(cinfo, 1, JTRC_DQT, n, prec); + + if (n >= NUM_QUANT_TBLS) + ERREXIT1(cinfo, JERR_DQT_INDEX, n); + + if (cinfo->quant_tbl_ptrs[n] == NULL) + cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo); + quant_ptr = cinfo->quant_tbl_ptrs[n]; + + for (i = 0; i < DCTSIZE2; i++) { + if (prec) + INPUT_2BYTES(cinfo, tmp, return FALSE); + else + INPUT_BYTE(cinfo, tmp, return FALSE); + /* We convert the zigzag-order table to natural array order. */ + quant_ptr->quantval[jpeg_natural_order[i]] = (UINT16) tmp; + } + + if (cinfo->err->trace_level >= 2) { + for (i = 0; i < DCTSIZE2; i += 8) { + TRACEMS8(cinfo, 2, JTRC_QUANTVALS, + quant_ptr->quantval[i], quant_ptr->quantval[i+1], + quant_ptr->quantval[i+2], quant_ptr->quantval[i+3], + quant_ptr->quantval[i+4], quant_ptr->quantval[i+5], + quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]); + } + } + + length -= DCTSIZE2+1; + if (prec) length -= DCTSIZE2; + } + + if (length != 0) + ERREXIT(cinfo, JERR_BAD_LENGTH); + + INPUT_SYNC(cinfo); + return TRUE; +} + + +LOCAL(boolean) +get_dri (j_decompress_ptr cinfo) +/* Process a DRI marker */ +{ + INT32 length; + unsigned int tmp; + INPUT_VARS(cinfo); + + INPUT_2BYTES(cinfo, length, return FALSE); + + if (length != 4) + ERREXIT(cinfo, JERR_BAD_LENGTH); + + INPUT_2BYTES(cinfo, tmp, return FALSE); + + TRACEMS1(cinfo, 1, JTRC_DRI, tmp); + + cinfo->restart_interval = tmp; + + INPUT_SYNC(cinfo); + return TRUE; +} + + +/* + * Routines for processing APPn and COM markers. + * These are either saved in memory or discarded, per application request. + * APP0 and APP14 are specially checked to see if they are + * JFIF and Adobe markers, respectively. + */ + +#define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */ +#define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */ +#define APPN_DATA_LEN 14 /* Must be the largest of the above!! */ + + +LOCAL(void) +examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data, + unsigned int datalen, INT32 remaining) +/* Examine first few bytes from an APP0. + * Take appropriate action if it is a JFIF marker. + * datalen is # of bytes at data[], remaining is length of rest of marker data. + */ +{ + INT32 totallen = (INT32) datalen + remaining; + + if (datalen >= APP0_DATA_LEN && + GETJOCTET(data[0]) == 0x4A && + GETJOCTET(data[1]) == 0x46 && + GETJOCTET(data[2]) == 0x49 && + GETJOCTET(data[3]) == 0x46 && + GETJOCTET(data[4]) == 0) { + /* Found JFIF APP0 marker: save info */ + cinfo->saw_JFIF_marker = TRUE; + cinfo->JFIF_major_version = GETJOCTET(data[5]); + cinfo->JFIF_minor_version = GETJOCTET(data[6]); + cinfo->density_unit = GETJOCTET(data[7]); + cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]); + cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]); + /* Check version. + * Major version must be 1, anything else signals an incompatible change. + * (We used to treat this as an error, but now it's a nonfatal warning, + * because some bozo at Hijaak couldn't read the spec.) + * Minor version should be 0..2, but process anyway if newer. + */ + if (cinfo->JFIF_major_version != 1) + WARNMS2(cinfo, JWRN_JFIF_MAJOR, + cinfo->JFIF_major_version, cinfo->JFIF_minor_version); + /* Generate trace messages */ + TRACEMS5(cinfo, 1, JTRC_JFIF, + cinfo->JFIF_major_version, cinfo->JFIF_minor_version, + cinfo->X_density, cinfo->Y_density, cinfo->density_unit); + /* Validate thumbnail dimensions and issue appropriate messages */ + if (GETJOCTET(data[12]) | GETJOCTET(data[13])) + TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL, + GETJOCTET(data[12]), GETJOCTET(data[13])); + totallen -= APP0_DATA_LEN; + if (totallen != + ((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3)) + TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen); + } else if (datalen >= 6 && + GETJOCTET(data[0]) == 0x4A && + GETJOCTET(data[1]) == 0x46 && + GETJOCTET(data[2]) == 0x58 && + GETJOCTET(data[3]) == 0x58 && + GETJOCTET(data[4]) == 0) { + /* Found JFIF "JFXX" extension APP0 marker */ + /* The library doesn't actually do anything with these, + * but we try to produce a helpful trace message. + */ + switch (GETJOCTET(data[5])) { + case 0x10: + TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen); + break; + case 0x11: + TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen); + break; + case 0x13: + TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen); + break; + default: + TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION, + GETJOCTET(data[5]), (int) totallen); + break; + } + } else { + /* Start of APP0 does not match "JFIF" or "JFXX", or too short */ + TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen); + } +} + + +LOCAL(void) +examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data, + unsigned int datalen, INT32 remaining) +/* Examine first few bytes from an APP14. + * Take appropriate action if it is an Adobe marker. + * datalen is # of bytes at data[], remaining is length of rest of marker data. + */ +{ + unsigned int version, flags0, flags1, transform; + + if (datalen >= APP14_DATA_LEN && + GETJOCTET(data[0]) == 0x41 && + GETJOCTET(data[1]) == 0x64 && + GETJOCTET(data[2]) == 0x6F && + GETJOCTET(data[3]) == 0x62 && + GETJOCTET(data[4]) == 0x65) { + /* Found Adobe APP14 marker */ + version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]); + flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]); + flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]); + transform = GETJOCTET(data[11]); + TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform); + cinfo->saw_Adobe_marker = TRUE; + cinfo->Adobe_transform = (UINT8) transform; + } else { + /* Start of APP14 does not match "Adobe", or too short */ + TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining)); + } +} + + +METHODDEF(boolean) +get_interesting_appn (j_decompress_ptr cinfo) +/* Process an APP0 or APP14 marker without saving it */ +{ + INT32 length; + JOCTET b[APPN_DATA_LEN]; + unsigned int i, numtoread; + INPUT_VARS(cinfo); + + INPUT_2BYTES(cinfo, length, return FALSE); + length -= 2; + + /* get the interesting part of the marker data */ + if (length >= APPN_DATA_LEN) + numtoread = APPN_DATA_LEN; + else if (length > 0) + numtoread = (unsigned int) length; + else + numtoread = 0; + for (i = 0; i < numtoread; i++) + INPUT_BYTE(cinfo, b[i], return FALSE); + length -= numtoread; + + /* process it */ + switch (cinfo->unread_marker) { + case M_APP0: + examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length); + break; + case M_APP14: + examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length); + break; + default: + /* can't get here unless jpeg_save_markers chooses wrong processor */ + ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); + break; + } + + /* skip any remaining data -- could be lots */ + INPUT_SYNC(cinfo); + if (length > 0) + (*cinfo->src->skip_input_data) (cinfo, (long) length); + + return TRUE; +} + + +#ifdef SAVE_MARKERS_SUPPORTED + +METHODDEF(boolean) +save_marker (j_decompress_ptr cinfo) +/* Save an APPn or COM marker into the marker list */ +{ + my_marker_ptr marker = (my_marker_ptr) cinfo->marker; + jpeg_saved_marker_ptr cur_marker = marker->cur_marker; + unsigned int bytes_read, data_length; + JOCTET FAR * data; + INT32 length = 0; + INPUT_VARS(cinfo); + + if (cur_marker == NULL) { + /* begin reading a marker */ + INPUT_2BYTES(cinfo, length, return FALSE); + length -= 2; + if (length >= 0) { /* watch out for bogus length word */ + /* figure out how much we want to save */ + unsigned int limit; + if (cinfo->unread_marker == (int) M_COM) + limit = marker->length_limit_COM; + else + limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0]; + if ((unsigned int) length < limit) + limit = (unsigned int) length; + /* allocate and initialize the marker item */ + cur_marker = (jpeg_saved_marker_ptr) + (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(struct jpeg_marker_struct) + limit); + cur_marker->next = NULL; + cur_marker->marker = (UINT8) cinfo->unread_marker; + cur_marker->original_length = (unsigned int) length; + cur_marker->data_length = limit; + /* data area is just beyond the jpeg_marker_struct */ + data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1); + marker->cur_marker = cur_marker; + marker->bytes_read = 0; + bytes_read = 0; + data_length = limit; + } else { + /* deal with bogus length word */ + bytes_read = data_length = 0; + data = NULL; + } + } else { + /* resume reading a marker */ + bytes_read = marker->bytes_read; + data_length = cur_marker->data_length; + data = cur_marker->data + bytes_read; + } + + while (bytes_read < data_length) { + INPUT_SYNC(cinfo); /* move the restart point to here */ + marker->bytes_read = bytes_read; + /* If there's not at least one byte in buffer, suspend */ + MAKE_BYTE_AVAIL(cinfo, return FALSE); + /* Copy bytes with reasonable rapidity */ + while (bytes_read < data_length && bytes_in_buffer > 0) { + *data++ = *next_input_byte++; + bytes_in_buffer--; + bytes_read++; + } + } + + /* Done reading what we want to read */ + if (cur_marker != NULL) { /* will be NULL if bogus length word */ + /* Add new marker to end of list */ + if (cinfo->marker_list == NULL) { + cinfo->marker_list = cur_marker; + } else { + jpeg_saved_marker_ptr prev = cinfo->marker_list; + while (prev->next != NULL) + prev = prev->next; + prev->next = cur_marker; + } + /* Reset pointer & calc remaining data length */ + data = cur_marker->data; + length = cur_marker->original_length - data_length; + } + /* Reset to initial state for next marker */ + marker->cur_marker = NULL; + + /* Process the marker if interesting; else just make a generic trace msg */ + switch (cinfo->unread_marker) { + case M_APP0: + examine_app0(cinfo, data, data_length, length); + break; + case M_APP14: + examine_app14(cinfo, data, data_length, length); + break; + default: + TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, + (int) (data_length + length)); + break; + } + + /* skip any remaining data -- could be lots */ + INPUT_SYNC(cinfo); /* do before skip_input_data */ + if (length > 0) + (*cinfo->src->skip_input_data) (cinfo, (long) length); + + return TRUE; +} + +#endif /* SAVE_MARKERS_SUPPORTED */ + + +METHODDEF(boolean) +skip_variable (j_decompress_ptr cinfo) +/* Skip over an unknown or uninteresting variable-length marker */ +{ + INT32 length; + INPUT_VARS(cinfo); + + INPUT_2BYTES(cinfo, length, return FALSE); + length -= 2; + + TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length); + + INPUT_SYNC(cinfo); /* do before skip_input_data */ + if (length > 0) + (*cinfo->src->skip_input_data) (cinfo, (long) length); + + return TRUE; +} + + +/* + * Find the next JPEG marker, save it in cinfo->unread_marker. + * Returns FALSE if had to suspend before reaching a marker; + * in that case cinfo->unread_marker is unchanged. + * + * Note that the result might not be a valid marker code, + * but it will never be 0 or FF. + */ + +LOCAL(boolean) +next_marker (j_decompress_ptr cinfo) +{ + int c; + INPUT_VARS(cinfo); + + for (;;) { + INPUT_BYTE(cinfo, c, return FALSE); + /* Skip any non-FF bytes. + * This may look a bit inefficient, but it will not occur in a valid file. + * We sync after each discarded byte so that a suspending data source + * can discard the byte from its buffer. + */ + while (c != 0xFF) { + cinfo->marker->discarded_bytes++; + INPUT_SYNC(cinfo); + INPUT_BYTE(cinfo, c, return FALSE); + } + /* This loop swallows any duplicate FF bytes. Extra FFs are legal as + * pad bytes, so don't count them in discarded_bytes. We assume there + * will not be so many consecutive FF bytes as to overflow a suspending + * data source's input buffer. + */ + do { + INPUT_BYTE(cinfo, c, return FALSE); + } while (c == 0xFF); + if (c != 0) + break; /* found a valid marker, exit loop */ + /* Reach here if we found a stuffed-zero data sequence (FF/00). + * Discard it and loop back to try again. + */ + cinfo->marker->discarded_bytes += 2; + INPUT_SYNC(cinfo); + } + + if (cinfo->marker->discarded_bytes != 0) { + WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c); + cinfo->marker->discarded_bytes = 0; + } + + cinfo->unread_marker = c; + + INPUT_SYNC(cinfo); + return TRUE; +} + + +LOCAL(boolean) +first_marker (j_decompress_ptr cinfo) +/* Like next_marker, but used to obtain the initial SOI marker. */ +/* For this marker, we do not allow preceding garbage or fill; otherwise, + * we might well scan an entire input file before realizing it ain't JPEG. + * If an application wants to process non-JFIF files, it must seek to the + * SOI before calling the JPEG library. + */ +{ + int c, c2; + INPUT_VARS(cinfo); + + INPUT_BYTE(cinfo, c, return FALSE); + INPUT_BYTE(cinfo, c2, return FALSE); + if (c != 0xFF || c2 != (int) M_SOI) + ERREXIT2(cinfo, JERR_NO_SOI, c, c2); + + cinfo->unread_marker = c2; + + INPUT_SYNC(cinfo); + return TRUE; +} + + +/* + * Read markers until SOS or EOI. + * + * Returns same codes as are defined for jpeg_consume_input: + * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. + */ + +METHODDEF(int) +read_markers (j_decompress_ptr cinfo) +{ + /* Outer loop repeats once for each marker. */ + for (;;) { + /* Collect the marker proper, unless we already did. */ + /* NB: first_marker() enforces the requirement that SOI appear first. */ + if (cinfo->unread_marker == 0) { + if (! cinfo->marker->saw_SOI) { + if (! first_marker(cinfo)) + return JPEG_SUSPENDED; + } else { + if (! next_marker(cinfo)) + return JPEG_SUSPENDED; + } + } + /* At this point cinfo->unread_marker contains the marker code and the + * input point is just past the marker proper, but before any parameters. + * A suspension will cause us to return with this state still true. + */ + switch (cinfo->unread_marker) { + case M_SOI: + if (! get_soi(cinfo)) + return JPEG_SUSPENDED; + break; + + case M_SOF0: /* Baseline */ + case M_SOF1: /* Extended sequential, Huffman */ + if (! get_sof(cinfo, JPROC_SEQUENTIAL, FALSE, DCTSIZE)) + return JPEG_SUSPENDED; + break; + + case M_SOF2: /* Progressive, Huffman */ + if (! get_sof(cinfo, JPROC_PROGRESSIVE, FALSE, DCTSIZE)) + return JPEG_SUSPENDED; + break; + + case M_SOF3: /* Lossless, Huffman */ + if (! get_sof(cinfo, JPROC_LOSSLESS, FALSE, 1)) + return JPEG_SUSPENDED; + break; + + case M_SOF9: /* Extended sequential, arithmetic */ + if (! get_sof(cinfo, JPROC_SEQUENTIAL, TRUE, DCTSIZE)) + return JPEG_SUSPENDED; + break; + + case M_SOF10: /* Progressive, arithmetic */ + if (! get_sof(cinfo, JPROC_PROGRESSIVE, TRUE, DCTSIZE)) + return JPEG_SUSPENDED; + break; + + case M_SOF11: /* Lossless, arithmetic */ + if (! get_sof(cinfo, JPROC_LOSSLESS, TRUE, 1)) + return JPEG_SUSPENDED; + break; + + /* Currently unsupported SOFn types */ + case M_SOF5: /* Differential sequential, Huffman */ + case M_SOF6: /* Differential progressive, Huffman */ + case M_SOF7: /* Differential lossless, Huffman */ + case M_JPG: /* Reserved for JPEG extensions */ + case M_SOF13: /* Differential sequential, arithmetic */ + case M_SOF14: /* Differential progressive, arithmetic */ + case M_SOF15: /* Differential lossless, arithmetic */ + ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker); + break; + + case M_SOS: + if (! get_sos(cinfo)) + return JPEG_SUSPENDED; + cinfo->unread_marker = 0; /* processed the marker */ + return JPEG_REACHED_SOS; + + case M_EOI: + TRACEMS(cinfo, 1, JTRC_EOI); + cinfo->unread_marker = 0; /* processed the marker */ + return JPEG_REACHED_EOI; + + case M_DAC: + if (! get_dac(cinfo)) + return JPEG_SUSPENDED; + break; + + case M_DHT: + if (! get_dht(cinfo)) + return JPEG_SUSPENDED; + break; + + case M_DQT: + if (! get_dqt(cinfo)) + return JPEG_SUSPENDED; + break; + + case M_DRI: + if (! get_dri(cinfo)) + return JPEG_SUSPENDED; + break; + + case M_APP0: + case M_APP1: + case M_APP2: + case M_APP3: + case M_APP4: + case M_APP5: + case M_APP6: + case M_APP7: + case M_APP8: + case M_APP9: + case M_APP10: + case M_APP11: + case M_APP12: + case M_APP13: + case M_APP14: + case M_APP15: + if (! (*((my_marker_ptr) cinfo->marker)->process_APPn[ + cinfo->unread_marker - (int) M_APP0]) (cinfo)) + return JPEG_SUSPENDED; + break; + + case M_COM: + if (! (*((my_marker_ptr) cinfo->marker)->process_COM) (cinfo)) + return JPEG_SUSPENDED; + break; + + case M_RST0: /* these are all parameterless */ + case M_RST1: + case M_RST2: + case M_RST3: + case M_RST4: + case M_RST5: + case M_RST6: + case M_RST7: + case M_TEM: + TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker); + break; + + case M_DNL: /* Ignore DNL ... perhaps the wrong thing */ + if (! skip_variable(cinfo)) + return JPEG_SUSPENDED; + break; + + default: /* must be DHP, EXP, JPGn, or RESn */ + /* For now, we treat the reserved markers as fatal errors since they are + * likely to be used to signal incompatible JPEG Part 3 extensions. + * Once the JPEG 3 version-number marker is well defined, this code + * ought to change! + */ + ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); + break; + } + /* Successfully processed marker, so reset state variable */ + cinfo->unread_marker = 0; + } /* end loop */ +} + + +/* + * Read a restart marker, which is expected to appear next in the datastream; + * if the marker is not there, take appropriate recovery action. + * Returns FALSE if suspension is required. + * + * This is called by the entropy decoder after it has read an appropriate + * number of MCUs. cinfo->unread_marker may be nonzero if the entropy decoder + * has already read a marker from the data source. Under normal conditions + * cinfo->unread_marker will be reset to 0 before returning; if not reset, + * it holds a marker which the decoder will be unable to read past. + */ + +METHODDEF(boolean) +read_restart_marker (j_decompress_ptr cinfo) +{ + /* Obtain a marker unless we already did. */ + /* Note that next_marker will complain if it skips any data. */ + if (cinfo->unread_marker == 0) { + if (! next_marker(cinfo)) + return FALSE; + } + + if (cinfo->unread_marker == + ((int) M_RST0 + cinfo->marker->next_restart_num)) { + /* Normal case --- swallow the marker and let entropy decoder continue */ + TRACEMS1(cinfo, 3, JTRC_RST, cinfo->marker->next_restart_num); + cinfo->unread_marker = 0; + } else { + /* Uh-oh, the restart markers have been messed up. */ + /* Let the data source manager determine how to resync. */ + if (! (*cinfo->src->resync_to_restart) (cinfo, + cinfo->marker->next_restart_num)) + return FALSE; + } + + /* Update next-restart state */ + cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7; + + return TRUE; +} + + +/* + * This is the default resync_to_restart method for data source managers + * to use if they don't have any better approach. Some data source managers + * may be able to back up, or may have additional knowledge about the data + * which permits a more intelligent recovery strategy; such managers would + * presumably supply their own resync method. + * + * read_restart_marker calls resync_to_restart if it finds a marker other than + * the restart marker it was expecting. (This code is *not* used unless + * a nonzero restart interval has been declared.) cinfo->unread_marker is + * the marker code actually found (might be anything, except 0 or FF). + * The desired restart marker number (0..7) is passed as a parameter. + * This routine is supposed to apply whatever error recovery strategy seems + * appropriate in order to position the input stream to the next data segment. + * Note that cinfo->unread_marker is treated as a marker appearing before + * the current data-source input point; usually it should be reset to zero + * before returning. + * Returns FALSE if suspension is required. + * + * This implementation is substantially constrained by wanting to treat the + * input as a data stream; this means we can't back up. Therefore, we have + * only the following actions to work with: + * 1. Simply discard the marker and let the entropy decoder resume at next + * byte of file. + * 2. Read forward until we find another marker, discarding intervening + * data. (In theory we could look ahead within the current bufferload, + * without having to discard data if we don't find the desired marker. + * This idea is not implemented here, in part because it makes behavior + * dependent on buffer size and chance buffer-boundary positions.) + * 3. Leave the marker unread (by failing to zero cinfo->unread_marker). + * This will cause the entropy decoder to process an empty data segment, + * inserting dummy zeroes, and then we will reprocess the marker. + * + * #2 is appropriate if we think the desired marker lies ahead, while #3 is + * appropriate if the found marker is a future restart marker (indicating + * that we have missed the desired restart marker, probably because it got + * corrupted). + * We apply #2 or #3 if the found marker is a restart marker no more than + * two counts behind or ahead of the expected one. We also apply #2 if the + * found marker is not a legal JPEG marker code (it's certainly bogus data). + * If the found marker is a restart marker more than 2 counts away, we do #1 + * (too much risk that the marker is erroneous; with luck we will be able to + * resync at some future point). + * For any valid non-restart JPEG marker, we apply #3. This keeps us from + * overrunning the end of a scan. An implementation limited to single-scan + * files might find it better to apply #2 for markers other than EOI, since + * any other marker would have to be bogus data in that case. + */ + +GLOBAL(boolean) +jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired) +{ + int marker = cinfo->unread_marker; + int action = 1; + + /* Always put up a warning. */ + WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired); + + /* Outer loop handles repeated decision after scanning forward. */ + for (;;) { + if (marker < (int) M_SOF0) + action = 2; /* invalid marker */ + else if (marker < (int) M_RST0 || marker > (int) M_RST7) + action = 3; /* valid non-restart marker */ + else { + if (marker == ((int) M_RST0 + ((desired+1) & 7)) || + marker == ((int) M_RST0 + ((desired+2) & 7))) + action = 3; /* one of the next two expected restarts */ + else if (marker == ((int) M_RST0 + ((desired-1) & 7)) || + marker == ((int) M_RST0 + ((desired-2) & 7))) + action = 2; /* a prior restart, so advance */ + else + action = 1; /* desired restart or too far away */ + } + TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action); + switch (action) { + case 1: + /* Discard marker and let entropy decoder resume processing. */ + cinfo->unread_marker = 0; + return TRUE; + case 2: + /* Scan to the next marker, and repeat the decision loop. */ + if (! next_marker(cinfo)) + return FALSE; + marker = cinfo->unread_marker; + break; + case 3: + /* Return without advancing past this marker. */ + /* Entropy decoder will be forced to process an empty segment. */ + return TRUE; + } + } /* end loop */ +} + + +/* + * Reset marker processing state to begin a fresh datastream. + */ + +METHODDEF(void) +reset_marker_reader (j_decompress_ptr cinfo) +{ + my_marker_ptr marker = (my_marker_ptr) cinfo->marker; + + cinfo->comp_info = NULL; /* until allocated by get_sof */ + cinfo->input_scan_number = 0; /* no SOS seen yet */ + cinfo->unread_marker = 0; /* no pending marker */ + marker->pub.saw_SOI = FALSE; /* set internal state too */ + marker->pub.saw_SOF = FALSE; + marker->pub.discarded_bytes = 0; + marker->cur_marker = NULL; +} + + +/* + * Initialize the marker reader module. + * This is called only once, when the decompression object is created. + */ + +GLOBAL(void) +jinit_marker_reader (j_decompress_ptr cinfo) +{ + my_marker_ptr marker; + int i; + + /* Create subobject in permanent pool */ + marker = (my_marker_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, + SIZEOF(my_marker_reader)); + cinfo->marker = (struct jpeg_marker_reader *) marker; + /* Initialize public method pointers */ + marker->pub.reset_marker_reader = reset_marker_reader; + marker->pub.read_markers = read_markers; + marker->pub.read_restart_marker = read_restart_marker; + /* Initialize COM/APPn processing. + * By default, we examine and then discard APP0 and APP14, + * but simply discard COM and all other APPn. + */ + marker->process_COM = skip_variable; + marker->length_limit_COM = 0; + for (i = 0; i < 16; i++) { + marker->process_APPn[i] = skip_variable; + marker->length_limit_APPn[i] = 0; + } + marker->process_APPn[0] = get_interesting_appn; + marker->process_APPn[14] = get_interesting_appn; + /* Reset marker processing state */ + reset_marker_reader(cinfo); +} + + +/* + * Control saving of COM and APPn markers into marker_list. + */ + +#ifdef SAVE_MARKERS_SUPPORTED + +GLOBAL(void) +jpeg_save_markers (j_decompress_ptr cinfo, int marker_code, + unsigned int length_limit) +{ + my_marker_ptr marker = (my_marker_ptr) cinfo->marker; + long maxlength; + jpeg_marker_parser_method processor; + + /* Length limit mustn't be larger than what we can allocate + * (should only be a concern in a 16-bit environment). + */ + maxlength = cinfo->mem->max_alloc_chunk - SIZEOF(struct jpeg_marker_struct); + if (((long) length_limit) > maxlength) + length_limit = (unsigned int) maxlength; + + /* Choose processor routine to use. + * APP0/APP14 have special requirements. + */ + if (length_limit) { + processor = save_marker; + /* If saving APP0/APP14, save at least enough for our internal use. */ + if (marker_code == (int) M_APP0 && length_limit < APP0_DATA_LEN) + length_limit = APP0_DATA_LEN; + else if (marker_code == (int) M_APP14 && length_limit < APP14_DATA_LEN) + length_limit = APP14_DATA_LEN; + } else { + processor = skip_variable; + /* If discarding APP0/APP14, use our regular on-the-fly processor. */ + if (marker_code == (int) M_APP0 || marker_code == (int) M_APP14) + processor = get_interesting_appn; + } + + if (marker_code == (int) M_COM) { + marker->process_COM = processor; + marker->length_limit_COM = length_limit; + } else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) { + marker->process_APPn[marker_code - (int) M_APP0] = processor; + marker->length_limit_APPn[marker_code - (int) M_APP0] = length_limit; + } else + ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); +} + +#endif /* SAVE_MARKERS_SUPPORTED */ + + +/* + * Install a special processing method for COM or APPn markers. + */ + +GLOBAL(void) +jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code, + jpeg_marker_parser_method routine) +{ + my_marker_ptr marker = (my_marker_ptr) cinfo->marker; + + if (marker_code == (int) M_COM) + marker->process_COM = routine; + else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) + marker->process_APPn[marker_code - (int) M_APP0] = routine; + else + ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); +} diff --git a/src/gdcmjpeg/jdmaster.c b/src/gdcmjpeg/jdmaster.c new file mode 100644 index 00000000..cb06e011 --- /dev/null +++ b/src/gdcmjpeg/jdmaster.c @@ -0,0 +1,460 @@ +/* + * jdmaster.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains master control logic for the JPEG decompressor. + * These routines are concerned with selecting the modules to be executed + * and with determining the number of passes and the work to be done in each + * pass. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Private state */ + +typedef struct { + struct jpeg_decomp_master pub; /* public fields */ + + int pass_number; /* # of passes completed */ + + boolean using_merged_upsample; /* TRUE if using merged upsample/cconvert */ + + /* Saved references to initialized quantizer modules, + * in case we need to switch modes. + */ + struct jpeg_color_quantizer * quantizer_1pass; + struct jpeg_color_quantizer * quantizer_2pass; +} my_decomp_master; + +typedef my_decomp_master * my_master_ptr; + + +/* + * Determine whether merged upsample/color conversion should be used. + * CRUCIAL: this must match the actual capabilities of jdmerge.c! + */ + +LOCAL(boolean) +use_merged_upsample (j_decompress_ptr cinfo) +{ +#ifdef UPSAMPLE_MERGING_SUPPORTED + /* Merging is the equivalent of plain box-filter upsampling */ + if (cinfo->do_fancy_upsampling || cinfo->CCIR601_sampling) + return FALSE; + /* jdmerge.c only supports YCC=>RGB color conversion */ + if (cinfo->jpeg_color_space != JCS_YCbCr || cinfo->num_components != 3 || + cinfo->out_color_space != JCS_RGB || + cinfo->out_color_components != RGB_PIXELSIZE) + return FALSE; + /* and it only handles 2h1v or 2h2v sampling ratios */ + if (cinfo->comp_info[0].h_samp_factor != 2 || + cinfo->comp_info[1].h_samp_factor != 1 || + cinfo->comp_info[2].h_samp_factor != 1 || + cinfo->comp_info[0].v_samp_factor > 2 || + cinfo->comp_info[1].v_samp_factor != 1 || + cinfo->comp_info[2].v_samp_factor != 1) + return FALSE; + /* furthermore, it doesn't work if each component has been + processed differently */ + if (cinfo->comp_info[0].codec_data_unit != cinfo->min_codec_data_unit || + cinfo->comp_info[1].codec_data_unit != cinfo->min_codec_data_unit || + cinfo->comp_info[2].codec_data_unit != cinfo->min_codec_data_unit) + return FALSE; + /* ??? also need to test for upsample-time rescaling, when & if supported */ + return TRUE; /* by golly, it'll work... */ +#else + return FALSE; +#endif +} + + +/* + * Compute output image dimensions and related values. + * NOTE: this is exported for possible use by application. + * Hence it mustn't do anything that can't be done twice. + * Also note that it may be called before the master module is initialized! + */ + +GLOBAL(void) +jpeg_calc_output_dimensions (j_decompress_ptr cinfo) +/* Do computations that are needed before master selection phase */ +{ + /* Prevent application from calling me at wrong times */ + if (cinfo->global_state != DSTATE_READY) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + (*cinfo->codec->calc_output_dimensions) (cinfo); + + /* Report number of components in selected colorspace. */ + /* Probably this should be in the color conversion module... */ + switch (cinfo->out_color_space) { + case JCS_GRAYSCALE: + cinfo->out_color_components = 1; + break; + case JCS_RGB: +#if RGB_PIXELSIZE != 3 + cinfo->out_color_components = RGB_PIXELSIZE; + break; +#endif /* else share code with YCbCr */ + case JCS_YCbCr: + cinfo->out_color_components = 3; + break; + case JCS_CMYK: + case JCS_YCCK: + cinfo->out_color_components = 4; + break; + default: /* else must be same colorspace as in file */ + cinfo->out_color_components = cinfo->num_components; + break; + } + cinfo->output_components = (cinfo->quantize_colors ? 1 : + cinfo->out_color_components); + + /* See if upsampler will want to emit more than one row at a time */ + if (use_merged_upsample(cinfo)) + cinfo->rec_outbuf_height = cinfo->max_v_samp_factor; + else + cinfo->rec_outbuf_height = 1; +} + + +/* + * Several decompression processes need to range-limit values to the range + * 0..MAXJSAMPLE; the input value may fall somewhat outside this range + * due to noise introduced by quantization, roundoff error, etc. These + * processes are inner loops and need to be as fast as possible. On most + * machines, particularly CPUs with pipelines or instruction prefetch, + * a (subscript-check-less) C table lookup + * x = sample_range_limit[x]; + * is faster than explicit tests + * if (x < 0) x = 0; + * else if (x > MAXJSAMPLE) x = MAXJSAMPLE; + * These processes all use a common table prepared by the routine below. + * + * For most steps we can mathematically guarantee that the initial value + * of x is within MAXJSAMPLE+1 of the legal range, so a table running from + * -(MAXJSAMPLE+1) to 2*MAXJSAMPLE+1 is sufficient. But for the initial + * limiting step (just after the IDCT), a wildly out-of-range value is + * possible if the input data is corrupt. To avoid any chance of indexing + * off the end of memory and getting a bad-pointer trap, we perform the + * post-IDCT limiting thus: + * x = range_limit[x & MASK]; + * where MASK is 2 bits wider than legal sample data, ie 10 bits for 8-bit + * samples. Under normal circumstances this is more than enough range and + * a correct output will be generated; with bogus input data the mask will + * cause wraparound, and we will safely generate a bogus-but-in-range output. + * For the post-IDCT step, we want to convert the data from signed to unsigned + * representation by adding CENTERJSAMPLE at the same time that we limit it. + * So the post-IDCT limiting table ends up looking like this: + * CENTERJSAMPLE,CENTERJSAMPLE+1,...,MAXJSAMPLE, + * MAXJSAMPLE (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times), + * 0 (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times), + * 0,1,...,CENTERJSAMPLE-1 + * Negative inputs select values from the upper half of the table after + * masking. + * + * We can save some space by overlapping the start of the post-IDCT table + * with the simpler range limiting table. The post-IDCT table begins at + * sample_range_limit + CENTERJSAMPLE. + * + * Note that the table is allocated in near data space on PCs; it's small + * enough and used often enough to justify this. + */ + +LOCAL(void) +prepare_range_limit_table (j_decompress_ptr cinfo) +/* Allocate and fill in the sample_range_limit table */ +{ + JSAMPLE * table; + int i; + + table = (JSAMPLE *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (5 * (MAXJSAMPLE+1) + CENTERJSAMPLE) * SIZEOF(JSAMPLE)); + table += (MAXJSAMPLE+1); /* allow negative subscripts of simple table */ + cinfo->sample_range_limit = table; + /* First segment of "simple" table: limit[x] = 0 for x < 0 */ + MEMZERO(table - (MAXJSAMPLE+1), (MAXJSAMPLE+1) * SIZEOF(JSAMPLE)); + /* Main part of "simple" table: limit[x] = x */ + for (i = 0; i <= MAXJSAMPLE; i++) + table[i] = (JSAMPLE) i; + table += CENTERJSAMPLE; /* Point to where post-IDCT table starts */ + /* End of simple table, rest of first half of post-IDCT table */ + for (i = CENTERJSAMPLE; i < 2*(MAXJSAMPLE+1); i++) + table[i] = MAXJSAMPLE; + /* Second half of post-IDCT table */ + MEMZERO(table + (2 * (MAXJSAMPLE+1)), + (2 * (MAXJSAMPLE+1) - CENTERJSAMPLE) * SIZEOF(JSAMPLE)); + MEMCOPY(table + (4 * (MAXJSAMPLE+1) - CENTERJSAMPLE), + cinfo->sample_range_limit, CENTERJSAMPLE * SIZEOF(JSAMPLE)); +} + + +/* + * Master selection of decompression modules. + * This is done once at jpeg_start_decompress time. We determine + * which modules will be used and give them appropriate initialization calls. + * We also initialize the decompressor input side to begin consuming data. + * + * Since jpeg_read_header has finished, we know what is in the SOF + * and (first) SOS markers. We also have all the application parameter + * settings. + */ + +LOCAL(void) +master_selection (j_decompress_ptr cinfo) +{ + my_master_ptr master = (my_master_ptr) cinfo->master; + long samplesperrow; + JDIMENSION jd_samplesperrow; + + /* Initialize dimensions and other stuff */ + jpeg_calc_output_dimensions(cinfo); + prepare_range_limit_table(cinfo); + + /* Width of an output scanline must be representable as JDIMENSION. */ + samplesperrow = (long) cinfo->output_width * (long) cinfo->out_color_components; + jd_samplesperrow = (JDIMENSION) samplesperrow; + if ((long) jd_samplesperrow != samplesperrow) + ERREXIT(cinfo, JERR_WIDTH_OVERFLOW); + + /* Initialize my private state */ + master->pass_number = 0; + master->using_merged_upsample = use_merged_upsample(cinfo); + + /* Color quantizer selection */ + master->quantizer_1pass = NULL; + master->quantizer_2pass = NULL; + /* No mode changes if not using buffered-image mode. */ + if (! cinfo->quantize_colors || ! cinfo->buffered_image) { + cinfo->enable_1pass_quant = FALSE; + cinfo->enable_external_quant = FALSE; + cinfo->enable_2pass_quant = FALSE; + } + if (cinfo->quantize_colors) { + if (cinfo->raw_data_out) + ERREXIT(cinfo, JERR_NOTIMPL); + /* 2-pass quantizer only works in 3-component color space. */ + if (cinfo->out_color_components != 3) { + cinfo->enable_1pass_quant = TRUE; + cinfo->enable_external_quant = FALSE; + cinfo->enable_2pass_quant = FALSE; + cinfo->colormap = NULL; + } else if (cinfo->colormap != NULL) { + cinfo->enable_external_quant = TRUE; + } else if (cinfo->two_pass_quantize) { + cinfo->enable_2pass_quant = TRUE; + } else { + cinfo->enable_1pass_quant = TRUE; + } + + if (cinfo->enable_1pass_quant) { +#ifdef QUANT_1PASS_SUPPORTED + jinit_1pass_quantizer(cinfo); + master->quantizer_1pass = cinfo->cquantize; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } + + /* We use the 2-pass code to map to external colormaps. */ + if (cinfo->enable_2pass_quant || cinfo->enable_external_quant) { +#ifdef QUANT_2PASS_SUPPORTED + jinit_2pass_quantizer(cinfo); + master->quantizer_2pass = cinfo->cquantize; +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } + /* If both quantizers are initialized, the 2-pass one is left active; + * this is necessary for starting with quantization to an external map. + */ + } + + /* Post-processing: in particular, color conversion first */ + if (! cinfo->raw_data_out) { + if (master->using_merged_upsample) { +#ifdef UPSAMPLE_MERGING_SUPPORTED + jinit_merged_upsampler(cinfo); /* does color conversion too */ +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else { + jinit_color_deconverter(cinfo); + jinit_upsampler(cinfo); + } + jinit_d_post_controller(cinfo, cinfo->enable_2pass_quant); + } + + /* Initialize principal buffer controllers. */ + if (! cinfo->raw_data_out) + jinit_d_main_controller(cinfo, FALSE /* never need full buffer here */); + + /* We can now tell the memory manager to allocate virtual arrays. */ + (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo); + + /* Initialize input side of decompressor to consume first scan. */ + (*cinfo->inputctl->start_input_pass) (cinfo); + +#ifdef D_MULTISCAN_FILES_SUPPORTED + /* If jpeg_start_decompress will read the whole file, initialize + * progress monitoring appropriately. The input step is counted + * as one pass. + */ + if (cinfo->progress != NULL && ! cinfo->buffered_image && + cinfo->inputctl->has_multiple_scans) { + int nscans; + /* Estimate number of scans to set pass_limit. */ + if (cinfo->process == JPROC_PROGRESSIVE) { + /* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */ + nscans = 2 + 3 * cinfo->num_components; + } else { + /* For a nonprogressive multiscan file, estimate 1 scan per component. */ + nscans = cinfo->num_components; + } + cinfo->progress->pass_counter = 0L; + cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans; + cinfo->progress->completed_passes = 0; + cinfo->progress->total_passes = (cinfo->enable_2pass_quant ? 3 : 2); + /* Count the input pass as done */ + master->pass_number++; + } +#endif /* D_MULTISCAN_FILES_SUPPORTED */ +} + + +/* + * Per-pass setup. + * This is called at the beginning of each output pass. We determine which + * modules will be active during this pass and give them appropriate + * start_pass calls. We also set is_dummy_pass to indicate whether this + * is a "real" output pass or a dummy pass for color quantization. + * (In the latter case, jdapistd.c will crank the pass to completion.) + */ + +METHODDEF(void) +prepare_for_output_pass (j_decompress_ptr cinfo) +{ + my_master_ptr master = (my_master_ptr) cinfo->master; + + if (master->pub.is_dummy_pass) { +#ifdef QUANT_2PASS_SUPPORTED + /* Final pass of 2-pass quantization */ + master->pub.is_dummy_pass = FALSE; + (*cinfo->cquantize->start_pass) (cinfo, FALSE); + (*cinfo->post->start_pass) (cinfo, JBUF_CRANK_DEST); + (*cinfo->main->start_pass) (cinfo, JBUF_CRANK_DEST); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif /* QUANT_2PASS_SUPPORTED */ + } else { + if (cinfo->quantize_colors && cinfo->colormap == NULL) { + /* Select new quantization method */ + if (cinfo->two_pass_quantize && cinfo->enable_2pass_quant) { + cinfo->cquantize = master->quantizer_2pass; + master->pub.is_dummy_pass = TRUE; + } else if (cinfo->enable_1pass_quant) { + cinfo->cquantize = master->quantizer_1pass; + } else { + ERREXIT(cinfo, JERR_MODE_CHANGE); + } + } + (*cinfo->codec->start_output_pass) (cinfo); + if (! cinfo->raw_data_out) { + if (! master->using_merged_upsample) + (*cinfo->cconvert->start_pass) (cinfo); + (*cinfo->upsample->start_pass) (cinfo); + if (cinfo->quantize_colors) + (*cinfo->cquantize->start_pass) (cinfo, master->pub.is_dummy_pass); + (*cinfo->post->start_pass) (cinfo, + (master->pub.is_dummy_pass ? JBUF_SAVE_AND_PASS : JBUF_PASS_THRU)); + (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU); + } + } + + /* Set up progress monitor's pass info if present */ + if (cinfo->progress != NULL) { + cinfo->progress->completed_passes = master->pass_number; + cinfo->progress->total_passes = master->pass_number + + (master->pub.is_dummy_pass ? 2 : 1); + /* In buffered-image mode, we assume one more output pass if EOI not + * yet reached, but no more passes if EOI has been reached. + */ + if (cinfo->buffered_image && ! cinfo->inputctl->eoi_reached) { + cinfo->progress->total_passes += (cinfo->enable_2pass_quant ? 2 : 1); + } + } +} + + +/* + * Finish up at end of an output pass. + */ + +METHODDEF(void) +finish_output_pass (j_decompress_ptr cinfo) +{ + my_master_ptr master = (my_master_ptr) cinfo->master; + + if (cinfo->quantize_colors) + (*cinfo->cquantize->finish_pass) (cinfo); + master->pass_number++; +} + + +#ifdef D_MULTISCAN_FILES_SUPPORTED + +/* + * Switch to a new external colormap between output passes. + */ + +GLOBAL(void) +jpeg_new_colormap (j_decompress_ptr cinfo) +{ + my_master_ptr master = (my_master_ptr) cinfo->master; + + /* Prevent application from calling me at wrong times */ + if (cinfo->global_state != DSTATE_BUFIMAGE) + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + + if (cinfo->quantize_colors && cinfo->enable_external_quant && + cinfo->colormap != NULL) { + /* Select 2-pass quantizer for external colormap use */ + cinfo->cquantize = master->quantizer_2pass; + /* Notify quantizer of colormap change */ + (*cinfo->cquantize->new_color_map) (cinfo); + master->pub.is_dummy_pass = FALSE; /* just in case */ + } else + ERREXIT(cinfo, JERR_MODE_CHANGE); +} + +#endif /* D_MULTISCAN_FILES_SUPPORTED */ + + +/* + * Initialize master decompression control and select active modules. + * This is performed at the start of jpeg_start_decompress. + */ + +GLOBAL(void) +jinit_master_decompress (j_decompress_ptr cinfo) +{ + my_master_ptr master; + + master = (my_master_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_decomp_master)); + cinfo->master = (struct jpeg_decomp_master *) master; + master->pub.prepare_for_output_pass = prepare_for_output_pass; + master->pub.finish_output_pass = finish_output_pass; + + master->pub.is_dummy_pass = FALSE; + + master_selection(cinfo); +} diff --git a/src/gdcmjpeg/jdmerge.c b/src/gdcmjpeg/jdmerge.c new file mode 100644 index 00000000..7a235959 --- /dev/null +++ b/src/gdcmjpeg/jdmerge.c @@ -0,0 +1,402 @@ +/* + * jdmerge.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains code for merged upsampling/color conversion. + * + * This file combines functions from jdsample.c and jdcolor.c; + * read those files first to understand what's going on. + * + * When the chroma components are to be upsampled by simple replication + * (ie, box filtering), we can save some work in color conversion by + * calculating all the output pixels corresponding to a pair of chroma + * samples at one time. In the conversion equations + * R = Y + K1 * Cr + * G = Y + K2 * Cb + K3 * Cr + * B = Y + K4 * Cb + * only the Y term varies among the group of pixels corresponding to a pair + * of chroma samples, so the rest of the terms can be calculated just once. + * At typical sampling ratios, this eliminates half or three-quarters of the + * multiplications needed for color conversion. + * + * This file currently provides implementations for the following cases: + * YCbCr => RGB color conversion only. + * Sampling ratios of 2h1v or 2h2v. + * No scaling needed at upsample time. + * Corner-aligned (non-CCIR601) sampling alignment. + * Other special cases could be added, but in most applications these are + * the only common cases. (For uncommon cases we fall back on the more + * general code in jdsample.c and jdcolor.c.) + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + +#ifdef UPSAMPLE_MERGING_SUPPORTED + + +/* Private subobject */ + +typedef struct { + struct jpeg_upsampler pub; /* public fields */ + + /* Pointer to routine to do actual upsampling/conversion of one row group */ + JMETHOD(void, upmethod, (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr, + JSAMPARRAY output_buf)); + + /* Private state for YCC->RGB conversion */ + int * Cr_r_tab; /* => table for Cr to R conversion */ + int * Cb_b_tab; /* => table for Cb to B conversion */ + INT32 * Cr_g_tab; /* => table for Cr to G conversion */ + INT32 * Cb_g_tab; /* => table for Cb to G conversion */ + + /* For 2:1 vertical sampling, we produce two output rows at a time. + * We need a "spare" row buffer to hold the second output row if the + * application provides just a one-row buffer; we also use the spare + * to discard the dummy last row if the image height is odd. + */ + JSAMPROW spare_row; + boolean spare_full; /* T if spare buffer is occupied */ + + JDIMENSION out_row_width; /* samples per output row */ + JDIMENSION rows_to_go; /* counts rows remaining in image */ +} my_upsampler; + +typedef my_upsampler * my_upsample_ptr; + +#define SCALEBITS 16 /* speediest right-shift on some machines */ +#define ONE_HALF ((INT32) 1 << (SCALEBITS-1)) +#define FIX(x) ((INT32) ((x) * (1L<RGB colorspace conversion. + * This is taken directly from jdcolor.c; see that file for more info. + */ + +LOCAL(void) +build_ycc_rgb_table (j_decompress_ptr cinfo) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + int i; + INT32 x; + SHIFT_TEMPS + + upsample->Cr_r_tab = (int *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(int)); + upsample->Cb_b_tab = (int *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(int)); + upsample->Cr_g_tab = (INT32 *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(INT32)); + upsample->Cb_g_tab = (INT32 *) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (MAXJSAMPLE+1) * SIZEOF(INT32)); + + for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) { + /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */ + /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */ + /* Cr=>R value is nearest int to 1.40200 * x */ + upsample->Cr_r_tab[i] = (int) + RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS); + /* Cb=>B value is nearest int to 1.77200 * x */ + upsample->Cb_b_tab[i] = (int) + RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS); + /* Cr=>G value is scaled-up -0.71414 * x */ + upsample->Cr_g_tab[i] = (- FIX(0.71414)) * x; + /* Cb=>G value is scaled-up -0.34414 * x */ + /* We also add in ONE_HALF so that need not do it in inner loop */ + upsample->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF; + } +} + + +/* + * Initialize for an upsampling pass. + */ + +METHODDEF(void) +start_pass_merged_upsample (j_decompress_ptr cinfo) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + + /* Mark the spare buffer empty */ + upsample->spare_full = FALSE; + /* Initialize total-height counter for detecting bottom of image */ + upsample->rows_to_go = cinfo->output_height; +} + + +/* + * Control routine to do upsampling (and color conversion). + * + * The control routine just handles the row buffering considerations. + */ + +METHODDEF(void) +merged_2v_upsample (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +/* 2:1 vertical sampling case: may need a spare row. */ +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + JSAMPROW work_ptrs[2]; + JDIMENSION num_rows; /* number of rows returned to caller */ + (void)in_row_groups_avail; + + if (upsample->spare_full) { + /* If we have a spare row saved from a previous cycle, just return it. */ + jcopy_sample_rows(& upsample->spare_row, 0, output_buf + *out_row_ctr, 0, + 1, upsample->out_row_width); + num_rows = 1; + upsample->spare_full = FALSE; + } else { + /* Figure number of rows to return to caller. */ + num_rows = 2; + /* Not more than the distance to the end of the image. */ + if (num_rows > upsample->rows_to_go) + num_rows = upsample->rows_to_go; + /* And not more than what the client can accept: */ + out_rows_avail -= *out_row_ctr; + if (num_rows > out_rows_avail) + num_rows = out_rows_avail; + /* Create output pointer array for upsampler. */ + work_ptrs[0] = output_buf[*out_row_ctr]; + if (num_rows > 1) { + work_ptrs[1] = output_buf[*out_row_ctr + 1]; + } else { + work_ptrs[1] = upsample->spare_row; + upsample->spare_full = TRUE; + } + /* Now do the upsampling. */ + (*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr, work_ptrs); + } + + /* Adjust counts */ + *out_row_ctr += num_rows; + upsample->rows_to_go -= num_rows; + /* When the buffer is emptied, declare this input row group consumed */ + if (! upsample->spare_full) + (*in_row_group_ctr)++; +} + + +METHODDEF(void) +merged_1v_upsample (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +/* 1:1 vertical sampling case: much easier, never need a spare row. */ +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + (void)in_row_groups_avail;(void)out_rows_avail; + + /* Just do the upsampling. */ + (*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr, + output_buf + *out_row_ctr); + /* Adjust counts */ + (*out_row_ctr)++; + (*in_row_group_ctr)++; +} + + +/* + * These are the routines invoked by the control routines to do + * the actual upsampling/conversion. One row group is processed per call. + * + * Note: since we may be writing directly into application-supplied buffers, + * we have to be honest about the output width; we can't assume the buffer + * has been rounded up to an even width. + */ + + +/* + * Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical. + */ + +METHODDEF(void) +h2v1_merged_upsample (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr, + JSAMPARRAY output_buf) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + register int y, cred, cgreen, cblue; + int cb, cr; + register JSAMPROW outptr; + JSAMPROW inptr0, inptr1, inptr2; + JDIMENSION col; + /* copy these pointers into registers if possible */ + register JSAMPLE * range_limit = cinfo->sample_range_limit; + int * Crrtab = upsample->Cr_r_tab; + int * Cbbtab = upsample->Cb_b_tab; + INT32 * Crgtab = upsample->Cr_g_tab; + INT32 * Cbgtab = upsample->Cb_g_tab; + SHIFT_TEMPS + + inptr0 = input_buf[0][in_row_group_ctr]; + inptr1 = input_buf[1][in_row_group_ctr]; + inptr2 = input_buf[2][in_row_group_ctr]; + outptr = output_buf[0]; + /* Loop for each pair of output pixels */ + for (col = cinfo->output_width >> 1; col > 0; col--) { + /* Do the chroma part of the calculation */ + cb = GETJSAMPLE(*inptr1++); + cr = GETJSAMPLE(*inptr2++); + cred = Crrtab[cr]; + cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); + cblue = Cbbtab[cb]; + /* Fetch 2 Y values and emit 2 pixels */ + y = GETJSAMPLE(*inptr0++); + outptr[RGB_RED] = range_limit[y + cred]; + outptr[RGB_GREEN] = range_limit[y + cgreen]; + outptr[RGB_BLUE] = range_limit[y + cblue]; + outptr += RGB_PIXELSIZE; + y = GETJSAMPLE(*inptr0++); + outptr[RGB_RED] = range_limit[y + cred]; + outptr[RGB_GREEN] = range_limit[y + cgreen]; + outptr[RGB_BLUE] = range_limit[y + cblue]; + outptr += RGB_PIXELSIZE; + } + /* If image width is odd, do the last output column separately */ + if (cinfo->output_width & 1) { + cb = GETJSAMPLE(*inptr1); + cr = GETJSAMPLE(*inptr2); + cred = Crrtab[cr]; + cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); + cblue = Cbbtab[cb]; + y = GETJSAMPLE(*inptr0); + outptr[RGB_RED] = range_limit[y + cred]; + outptr[RGB_GREEN] = range_limit[y + cgreen]; + outptr[RGB_BLUE] = range_limit[y + cblue]; + } +} + + +/* + * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical. + */ + +METHODDEF(void) +h2v2_merged_upsample (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr, + JSAMPARRAY output_buf) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + register int y, cred, cgreen, cblue; + int cb, cr; + register JSAMPROW outptr0, outptr1; + JSAMPROW inptr00, inptr01, inptr1, inptr2; + JDIMENSION col; + /* copy these pointers into registers if possible */ + register JSAMPLE * range_limit = cinfo->sample_range_limit; + int * Crrtab = upsample->Cr_r_tab; + int * Cbbtab = upsample->Cb_b_tab; + INT32 * Crgtab = upsample->Cr_g_tab; + INT32 * Cbgtab = upsample->Cb_g_tab; + SHIFT_TEMPS + + inptr00 = input_buf[0][in_row_group_ctr*2]; + inptr01 = input_buf[0][in_row_group_ctr*2 + 1]; + inptr1 = input_buf[1][in_row_group_ctr]; + inptr2 = input_buf[2][in_row_group_ctr]; + outptr0 = output_buf[0]; + outptr1 = output_buf[1]; + /* Loop for each group of output pixels */ + for (col = cinfo->output_width >> 1; col > 0; col--) { + /* Do the chroma part of the calculation */ + cb = GETJSAMPLE(*inptr1++); + cr = GETJSAMPLE(*inptr2++); + cred = Crrtab[cr]; + cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); + cblue = Cbbtab[cb]; + /* Fetch 4 Y values and emit 4 pixels */ + y = GETJSAMPLE(*inptr00++); + outptr0[RGB_RED] = range_limit[y + cred]; + outptr0[RGB_GREEN] = range_limit[y + cgreen]; + outptr0[RGB_BLUE] = range_limit[y + cblue]; + outptr0 += RGB_PIXELSIZE; + y = GETJSAMPLE(*inptr00++); + outptr0[RGB_RED] = range_limit[y + cred]; + outptr0[RGB_GREEN] = range_limit[y + cgreen]; + outptr0[RGB_BLUE] = range_limit[y + cblue]; + outptr0 += RGB_PIXELSIZE; + y = GETJSAMPLE(*inptr01++); + outptr1[RGB_RED] = range_limit[y + cred]; + outptr1[RGB_GREEN] = range_limit[y + cgreen]; + outptr1[RGB_BLUE] = range_limit[y + cblue]; + outptr1 += RGB_PIXELSIZE; + y = GETJSAMPLE(*inptr01++); + outptr1[RGB_RED] = range_limit[y + cred]; + outptr1[RGB_GREEN] = range_limit[y + cgreen]; + outptr1[RGB_BLUE] = range_limit[y + cblue]; + outptr1 += RGB_PIXELSIZE; + } + /* If image width is odd, do the last output column separately */ + if (cinfo->output_width & 1) { + cb = GETJSAMPLE(*inptr1); + cr = GETJSAMPLE(*inptr2); + cred = Crrtab[cr]; + cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS); + cblue = Cbbtab[cb]; + y = GETJSAMPLE(*inptr00); + outptr0[RGB_RED] = range_limit[y + cred]; + outptr0[RGB_GREEN] = range_limit[y + cgreen]; + outptr0[RGB_BLUE] = range_limit[y + cblue]; + y = GETJSAMPLE(*inptr01); + outptr1[RGB_RED] = range_limit[y + cred]; + outptr1[RGB_GREEN] = range_limit[y + cgreen]; + outptr1[RGB_BLUE] = range_limit[y + cblue]; + } +} + + +/* + * Module initialization routine for merged upsampling/color conversion. + * + * NB: this is called under the conditions determined by use_merged_upsample() + * in jdmaster.c. That routine MUST correspond to the actual capabilities + * of this module; no safety checks are made here. + */ + +GLOBAL(void) +jinit_merged_upsampler (j_decompress_ptr cinfo) +{ + my_upsample_ptr upsample; + + upsample = (my_upsample_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_upsampler)); + cinfo->upsample = (struct jpeg_upsampler *) upsample; + upsample->pub.start_pass = start_pass_merged_upsample; + upsample->pub.need_context_rows = FALSE; + + upsample->out_row_width = cinfo->output_width * cinfo->out_color_components; + + if (cinfo->max_v_samp_factor == 2) { + upsample->pub.upsample = merged_2v_upsample; + upsample->upmethod = h2v2_merged_upsample; + /* Allocate a spare row buffer */ + upsample->spare_row = (JSAMPROW) + (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, + (size_t) (upsample->out_row_width * SIZEOF(JSAMPLE))); + } else { + upsample->pub.upsample = merged_1v_upsample; + upsample->upmethod = h2v1_merged_upsample; + /* No spare row needed */ + upsample->spare_row = NULL; + } + + build_ycc_rgb_table(cinfo); +} + +#endif /* UPSAMPLE_MERGING_SUPPORTED */ diff --git a/src/gdcmjpeg/jdphuff.c b/src/gdcmjpeg/jdphuff.c new file mode 100644 index 00000000..7baaff92 --- /dev/null +++ b/src/gdcmjpeg/jdphuff.c @@ -0,0 +1,675 @@ +/* + * jdphuff.c + * + * Copyright (C) 1995-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy decoding routines for progressive JPEG. + * + * Much of the complexity here has to do with supporting input suspension. + * If the data source module demands suspension, we want to be able to back + * up to the start of the current MCU. To do this, we copy state variables + * into local working storage, and update them back to the permanent + * storage only upon successful completion of an MCU. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy subsystem */ +#include "jdhuff.h" /* Declarations shared with jd*huff.c */ + + +#ifdef D_PROGRESSIVE_SUPPORTED + +/* + * Private entropy decoder object for progressive Huffman decoding. + * + * The savable_state subrecord contains fields that change within an MCU, + * but must not be updated permanently until we complete the MCU. + */ + +typedef struct { + unsigned int EOBRUN; /* remaining EOBs in EOBRUN */ + int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */ +} savable_state; + +/* This macro is to work around compilers with missing or broken + * structure assignment. You'll need to fix this code if you have + * such a compiler and you change MAX_COMPS_IN_SCAN. + */ + +#ifndef NO_STRUCT_ASSIGN +#define ASSIGN_STATE(dest,src) ((dest) = (src)) +#else +#if MAX_COMPS_IN_SCAN == 4 +#define ASSIGN_STATE(dest,src) \ + ((dest).EOBRUN = (src).EOBRUN, \ + (dest).last_dc_val[0] = (src).last_dc_val[0], \ + (dest).last_dc_val[1] = (src).last_dc_val[1], \ + (dest).last_dc_val[2] = (src).last_dc_val[2], \ + (dest).last_dc_val[3] = (src).last_dc_val[3]) +#endif +#endif + + +typedef struct { + huffd_common_fields; /* Fields shared with other entropy decoders */ + + /* These fields are loaded into local variables at start of each MCU. + * In case of suspension, we exit WITHOUT updating them. + */ + savable_state saved; /* Other state at start of MCU */ + + /* These fields are NOT loaded into local working state. */ + unsigned int restarts_to_go; /* MCUs left in this restart interval */ + + /* Pointers to derived tables (these workspaces have image lifespan) */ + d_derived_tbl * derived_tbls[NUM_HUFF_TBLS]; + + d_derived_tbl * ac_derived_tbl; /* active table during an AC scan */ +} phuff_entropy_decoder; + +typedef phuff_entropy_decoder * phuff_entropy_ptr; + +/* Forward declarations */ +METHODDEF(boolean) decode_mcu_DC_first JPP((j_decompress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(boolean) decode_mcu_AC_first JPP((j_decompress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(boolean) decode_mcu_DC_refine JPP((j_decompress_ptr cinfo, + JBLOCKROW *MCU_data)); +METHODDEF(boolean) decode_mcu_AC_refine JPP((j_decompress_ptr cinfo, + JBLOCKROW *MCU_data)); + + +/* + * Initialize for a Huffman-compressed scan. + */ + +METHODDEF(void) +start_pass_phuff_decoder (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyd->entropy_private; + boolean is_DC_band, bad; + int ci, coefi, tbl; + int *coef_bit_ptr; + jpeg_component_info * compptr; + + is_DC_band = (cinfo->Ss == 0); + + /* Validate scan parameters */ + bad = FALSE; + if (is_DC_band) { + if (cinfo->Se != 0) + bad = TRUE; + } else { + /* need not check Ss/Se < 0 since they came from unsigned bytes */ + if (cinfo->Ss > cinfo->Se || cinfo->Se >= DCTSIZE2) + bad = TRUE; + /* AC scans may have only one component */ + if (cinfo->comps_in_scan != 1) + bad = TRUE; + } + if (cinfo->Ah != 0) { + /* Successive approximation refinement scan: must have Al = Ah-1. */ + if (cinfo->Al != cinfo->Ah-1) + bad = TRUE; + } + if (cinfo->Al > 13) /* need not check for < 0 */ + bad = TRUE; + /* Arguably the maximum Al value should be less than 13 for 8-bit precision, + * but the spec doesn't say so, and we try to be liberal about what we + * accept. Note: large Al values could result in out-of-range DC + * coefficients during early scans, leading to bizarre displays due to + * overflows in the IDCT math. But we won't crash. + */ + if (bad) + ERREXIT4(cinfo, JERR_BAD_PROGRESSION, + cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al); + /* Update progression status, and verify that scan order is legal. + * Note that inter-scan inconsistencies are treated as warnings + * not fatal errors ... not clear if this is right way to behave. + */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + int cindex = cinfo->cur_comp_info[ci]->component_index; + coef_bit_ptr = & cinfo->coef_bits[cindex][0]; + if (!is_DC_band && coef_bit_ptr[0] < 0) /* AC without prior DC scan */ + WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0); + for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) { + int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi]; + if (cinfo->Ah != expected) + WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi); + coef_bit_ptr[coefi] = cinfo->Al; + } + } + + /* Select MCU decoding routine */ + if (cinfo->Ah == 0) { + if (is_DC_band) + lossyd->entropy_decode_mcu = decode_mcu_DC_first; + else + lossyd->entropy_decode_mcu = decode_mcu_AC_first; + } else { + if (is_DC_band) + lossyd->entropy_decode_mcu = decode_mcu_DC_refine; + else + lossyd->entropy_decode_mcu = decode_mcu_AC_refine; + } + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + /* Make sure requested tables are present, and compute derived tables. + * We may build same derived table more than once, but it's not expensive. + */ + if (is_DC_band) { + if (cinfo->Ah == 0) { /* DC refinement needs no table */ + tbl = compptr->dc_tbl_no; + jpeg_make_d_derived_tbl(cinfo, TRUE, tbl, + & entropy->derived_tbls[tbl]); + } + } else { + tbl = compptr->ac_tbl_no; + jpeg_make_d_derived_tbl(cinfo, FALSE, tbl, + & entropy->derived_tbls[tbl]); + /* remember the single active table */ + entropy->ac_derived_tbl = entropy->derived_tbls[tbl]; + } + /* Initialize DC predictions to 0 */ + entropy->saved.last_dc_val[ci] = 0; + } + + /* Initialize bitread state variables */ + entropy->bitstate.bits_left = 0; + entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */ + entropy->insufficient_data = FALSE; + + /* Initialize private state variables */ + entropy->saved.EOBRUN = 0; + + /* Initialize restart counter */ + entropy->restarts_to_go = cinfo->restart_interval; +} + + +/* + * Figure F.12: extend sign bit. + * On some machines, a shift and add will be faster than a table lookup. + */ + +#ifdef AVOID_TABLES + +#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x)) + +#else + +#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x)) + +static const int extend_test[16] = /* entry n is 2**(n-1) */ + { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, + 0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 }; + +static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */ + { 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1, + ((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1, + ((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1, + ((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 }; + +#endif /* AVOID_TABLES */ + + +/* + * Check for a restart marker & resynchronize decoder. + * Returns FALSE if must suspend. + */ + +LOCAL(boolean) +process_restart (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyd->entropy_private; + int ci; + + /* Throw away any unused bits remaining in bit buffer; */ + /* include any full bytes in next_marker's count of discarded bytes */ + cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8; + entropy->bitstate.bits_left = 0; + + /* Advance past the RSTn marker */ + if (! (*cinfo->marker->read_restart_marker) (cinfo)) + return FALSE; + + /* Re-initialize DC predictions to 0 */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) + entropy->saved.last_dc_val[ci] = 0; + /* Re-init EOB run count, too */ + entropy->saved.EOBRUN = 0; + + /* Reset restart counter */ + entropy->restarts_to_go = cinfo->restart_interval; + + /* Reset out-of-data flag, unless read_restart_marker left us smack up + * against a marker. In that case we will end up treating the next data + * segment as empty, and we can avoid producing bogus output pixels by + * leaving the flag set. + */ + if (cinfo->unread_marker == 0) + entropy->insufficient_data = FALSE; + + return TRUE; +} + + +/* + * Huffman MCU decoding. + * Each of these routines decodes and returns one MCU's worth of + * Huffman-compressed coefficients. + * The coefficients are reordered from zigzag order into natural array order, + * but are not dequantized. + * + * The i'th block of the MCU is stored into the block pointed to by + * MCU_data[i]. WE ASSUME THIS AREA IS INITIALLY ZEROED BY THE CALLER. + * + * We return FALSE if data source requested suspension. In that case no + * changes have been made to permanent state. (Exception: some output + * coefficients may already have been assigned. This is harmless for + * spectral selection, since we'll just re-assign them on the next call. + * Successive approximation AC refinement has to be more careful, however.) + */ + +/* + * MCU decoding for DC initial scan (either spectral selection, + * or first pass of successive approximation). + */ + +METHODDEF(boolean) +decode_mcu_DC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyd->entropy_private; + int Al = cinfo->Al; + register int s, r; + int blkn, ci; + JBLOCKROW block; + BITREAD_STATE_VARS; + savable_state state; + d_derived_tbl * tbl; + jpeg_component_info * compptr; + + /* Process restart marker if needed; may have to suspend */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! process_restart(cinfo)) + return FALSE; + } + + /* If we've run out of data, just leave the MCU set to zeroes. + * This way, we return uniform gray for the remainder of the segment. + */ + if (! entropy->insufficient_data) { + + /* Load up working state */ + BITREAD_LOAD_STATE(cinfo,entropy->bitstate); + ASSIGN_STATE(state, entropy->saved); + + /* Outer loop handles each block in the MCU */ + + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + block = MCU_data[blkn]; + ci = cinfo->MCU_membership[blkn]; + compptr = cinfo->cur_comp_info[ci]; + tbl = entropy->derived_tbls[compptr->dc_tbl_no]; + + /* Decode a single block's worth of coefficients */ + + /* Section F.2.2.1: decode the DC coefficient difference */ + HUFF_DECODE(s, br_state, tbl, return FALSE, label1); + if (s) { + CHECK_BIT_BUFFER(br_state, s, return FALSE); + r = GET_BITS(s); + s = HUFF_EXTEND(r, s); + } + + /* Convert DC difference to actual value, update last_dc_val */ + s += state.last_dc_val[ci]; + state.last_dc_val[ci] = s; + /* Scale and output the coefficient (assumes jpeg_natural_order[0]=0) */ + (*block)[0] = (JCOEF) (s << Al); + } + + /* Completed MCU, so update state */ + BITREAD_SAVE_STATE(cinfo,entropy->bitstate); + ASSIGN_STATE(entropy->saved, state); + } + + /* Account for restart interval (no-op if not using restarts) */ + entropy->restarts_to_go--; + + return TRUE; +} + + +/* + * MCU decoding for AC initial scan (either spectral selection, + * or first pass of successive approximation). + */ + +METHODDEF(boolean) +decode_mcu_AC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyd->entropy_private; + int Se = cinfo->Se; + int Al = cinfo->Al; + register int s, k, r; + unsigned int EOBRUN; + JBLOCKROW block; + BITREAD_STATE_VARS; + d_derived_tbl * tbl; + + /* Process restart marker if needed; may have to suspend */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! process_restart(cinfo)) + return FALSE; + } + + /* If we've run out of data, just leave the MCU set to zeroes. + * This way, we return uniform gray for the remainder of the segment. + */ + if (! entropy->insufficient_data) { + + /* Load up working state. + * We can avoid loading/saving bitread state if in an EOB run. + */ + EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */ + + /* There is always only one block per MCU */ + + if (EOBRUN > 0) /* if it's a band of zeroes... */ + EOBRUN--; /* ...process it now (we do nothing) */ + else { + BITREAD_LOAD_STATE(cinfo,entropy->bitstate); + block = MCU_data[0]; + tbl = entropy->ac_derived_tbl; + + for (k = cinfo->Ss; k <= Se; k++) { + HUFF_DECODE(s, br_state, tbl, return FALSE, label2); + r = s >> 4; + s &= 15; + if (s) { + k += r; + CHECK_BIT_BUFFER(br_state, s, return FALSE); + r = GET_BITS(s); + s = HUFF_EXTEND(r, s); + /* Scale and output coefficient in natural (dezigzagged) order */ + (*block)[jpeg_natural_order[k]] = (JCOEF) (s << Al); + } else { + if (r == 15) { /* ZRL */ + k += 15; /* skip 15 zeroes in band */ + } else { /* EOBr, run length is 2^r + appended bits */ + EOBRUN = 1 << r; + if (r) { /* EOBr, r > 0 */ + CHECK_BIT_BUFFER(br_state, r, return FALSE); + r = GET_BITS(r); + EOBRUN += r; + } + EOBRUN--; /* this band is processed at this moment */ + break; /* force end-of-band */ + } + } + } + + BITREAD_SAVE_STATE(cinfo,entropy->bitstate); + } + + /* Completed MCU, so update state */ + entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */ + } + + /* Account for restart interval (no-op if not using restarts) */ + entropy->restarts_to_go--; + + return TRUE; +} + + +/* + * MCU decoding for DC successive approximation refinement scan. + * Note: we assume such scans can be multi-component, although the spec + * is not very clear on the point. + */ + +METHODDEF(boolean) +decode_mcu_DC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyd->entropy_private; + int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */ + int blkn; + JBLOCKROW block; + BITREAD_STATE_VARS; + + /* Process restart marker if needed; may have to suspend */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! process_restart(cinfo)) + return FALSE; + } + + /* Not worth the cycles to check insufficient_data here, + * since we will not change the data anyway if we read zeroes. + */ + + /* Load up working state */ + BITREAD_LOAD_STATE(cinfo,entropy->bitstate); + + /* Outer loop handles each block in the MCU */ + + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + block = MCU_data[blkn]; + + /* Encoded data is simply the next bit of the two's-complement DC value */ + CHECK_BIT_BUFFER(br_state, 1, return FALSE); + if (GET_BITS(1)) + (*block)[0] |= p1; + /* Note: since we use |=, repeating the assignment later is safe */ + } + + /* Completed MCU, so update state */ + BITREAD_SAVE_STATE(cinfo,entropy->bitstate); + + /* Account for restart interval (no-op if not using restarts) */ + entropy->restarts_to_go--; + + return TRUE; +} + + +/* + * MCU decoding for AC successive approximation refinement scan. + */ + +METHODDEF(boolean) +decode_mcu_AC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy = (phuff_entropy_ptr) lossyd->entropy_private; + int Se = cinfo->Se; + int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */ + int m1 = (-1) << cinfo->Al; /* -1 in the bit position being coded */ + register int s, k, r; + unsigned int EOBRUN; + JBLOCKROW block; + JCOEFPTR thiscoef; + BITREAD_STATE_VARS; + d_derived_tbl * tbl; + int num_newnz; + int newnz_pos[DCTSIZE2]; + + /* Process restart marker if needed; may have to suspend */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! process_restart(cinfo)) + return FALSE; + } + + /* If we've run out of data, don't modify the MCU. + */ + if (! entropy->insufficient_data) { + + /* Load up working state */ + BITREAD_LOAD_STATE(cinfo,entropy->bitstate); + EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */ + + /* There is always only one block per MCU */ + block = MCU_data[0]; + tbl = entropy->ac_derived_tbl; + + /* If we are forced to suspend, we must undo the assignments to any newly + * nonzero coefficients in the block, because otherwise we'd get confused + * next time about which coefficients were already nonzero. + * But we need not undo addition of bits to already-nonzero coefficients; + * instead, we can test the current bit to see if we already did it. + */ + num_newnz = 0; + + /* initialize coefficient loop counter to start of band */ + k = cinfo->Ss; + + if (EOBRUN == 0) { + for (; k <= Se; k++) { + HUFF_DECODE(s, br_state, tbl, goto undoit, label3); + r = s >> 4; + s &= 15; + if (s) { + if (s != 1) /* size of new coef should always be 1 */ + WARNMS(cinfo, JWRN_HUFF_BAD_CODE); + CHECK_BIT_BUFFER(br_state, 1, goto undoit); + if (GET_BITS(1)) + s = p1; /* newly nonzero coef is positive */ + else + s = m1; /* newly nonzero coef is negative */ + } else { + if (r != 15) { + EOBRUN = 1 << r; /* EOBr, run length is 2^r + appended bits */ + if (r) { + CHECK_BIT_BUFFER(br_state, r, goto undoit); + r = GET_BITS(r); + EOBRUN += r; + } + break; /* rest of block is handled by EOB logic */ + } + /* note s = 0 for processing ZRL */ + } + /* Advance over already-nonzero coefs and r still-zero coefs, + * appending correction bits to the nonzeroes. A correction bit is 1 + * if the absolute value of the coefficient must be increased. + */ + do { + thiscoef = *block + jpeg_natural_order[k]; + if (*thiscoef != 0) { + CHECK_BIT_BUFFER(br_state, 1, goto undoit); + if (GET_BITS(1)) { + if ((*thiscoef & p1) == 0) { /* do nothing if already set it */ + if (*thiscoef >= 0) + *thiscoef += p1; + else + *thiscoef += m1; + } + } + } else { + if (--r < 0) + break; /* reached target zero coefficient */ + } + k++; + } while (k <= Se); + if (s) { + int pos = jpeg_natural_order[k]; + /* Output newly nonzero coefficient */ + (*block)[pos] = (JCOEF) s; + /* Remember its position in case we have to suspend */ + newnz_pos[num_newnz++] = pos; + } + } + } + + if (EOBRUN > 0) { + /* Scan any remaining coefficient positions after the end-of-band + * (the last newly nonzero coefficient, if any). Append a correction + * bit to each already-nonzero coefficient. A correction bit is 1 + * if the absolute value of the coefficient must be increased. + */ + for (; k <= Se; k++) { + thiscoef = *block + jpeg_natural_order[k]; + if (*thiscoef != 0) { + CHECK_BIT_BUFFER(br_state, 1, goto undoit); + if (GET_BITS(1)) { + if ((*thiscoef & p1) == 0) { /* do nothing if already changed it */ + if (*thiscoef >= 0) + *thiscoef += p1; + else + *thiscoef += m1; + } + } + } + } + /* Count one block completed in EOB run */ + EOBRUN--; + } + + /* Completed MCU, so update state */ + BITREAD_SAVE_STATE(cinfo,entropy->bitstate); + entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */ + } + + /* Account for restart interval (no-op if not using restarts) */ + entropy->restarts_to_go--; + + return TRUE; + +undoit: + /* Re-zero any output coefficients that we made newly nonzero */ + while (num_newnz > 0) + (*block)[newnz_pos[--num_newnz]] = 0; + + return FALSE; +} + + +/* + * Module initialization routine for progressive Huffman entropy decoding. + */ + +GLOBAL(void) +jinit_phuff_decoder (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + phuff_entropy_ptr entropy; + int *coef_bit_ptr; + int ci, i; + + entropy = (phuff_entropy_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(phuff_entropy_decoder)); + lossyd->entropy_private = (void *) entropy; + lossyd->entropy_start_pass = start_pass_phuff_decoder; + + /* Mark derived tables unallocated */ + for (i = 0; i < NUM_HUFF_TBLS; i++) { + entropy->derived_tbls[i] = NULL; + } + + /* Create progression status table */ + cinfo->coef_bits = (int (*)[DCTSIZE2]) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + cinfo->num_components*DCTSIZE2*SIZEOF(int)); + coef_bit_ptr = & cinfo->coef_bits[0][0]; + for (ci = 0; ci < cinfo->num_components; ci++) + for (i = 0; i < DCTSIZE2; i++) + *coef_bit_ptr++ = -1; +} + +#endif /* D_PROGRESSIVE_SUPPORTED */ diff --git a/src/gdcmjpeg/jdpostct.c b/src/gdcmjpeg/jdpostct.c new file mode 100644 index 00000000..760eb19a --- /dev/null +++ b/src/gdcmjpeg/jdpostct.c @@ -0,0 +1,292 @@ +/* + * jdpostct.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the decompression postprocessing controller. + * This controller manages the upsampling, color conversion, and color + * quantization/reduction steps; specifically, it controls the buffering + * between upsample/color conversion and color quantization/reduction. + * + * If no color quantization/reduction is required, then this module has no + * work to do, and it just hands off to the upsample/color conversion code. + * An integrated upsample/convert/quantize process would replace this module + * entirely. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Private buffer controller object */ + +typedef struct { + struct jpeg_d_post_controller pub; /* public fields */ + + /* Color quantization source buffer: this holds output data from + * the upsample/color conversion step to be passed to the quantizer. + * For two-pass color quantization, we need a full-image buffer; + * for one-pass operation, a strip buffer is sufficient. + */ + jvirt_sarray_ptr whole_image; /* virtual array, or NULL if one-pass */ + JSAMPARRAY buffer; /* strip buffer, or current strip of virtual */ + JDIMENSION strip_height; /* buffer size in rows */ + /* for two-pass mode only: */ + JDIMENSION starting_row; /* row # of first row in current strip */ + JDIMENSION next_row; /* index of next row to fill/empty in strip */ +} my_post_controller; + +typedef my_post_controller * my_post_ptr; + + +/* Forward declarations */ +METHODDEF(void) post_process_1pass + JPP((j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail)); +#ifdef QUANT_2PASS_SUPPORTED +METHODDEF(void) post_process_prepass + JPP((j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail)); +METHODDEF(void) post_process_2pass + JPP((j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail)); +#endif + + +/* + * Initialize for a processing pass. + */ + +METHODDEF(void) +start_pass_dpost (j_decompress_ptr cinfo, J_BUF_MODE pass_mode) +{ + my_post_ptr post = (my_post_ptr) cinfo->post; + + switch (pass_mode) { + case JBUF_PASS_THRU: + if (cinfo->quantize_colors) { + /* Single-pass processing with color quantization. */ + post->pub.post_process_data = post_process_1pass; + /* We could be doing buffered-image output before starting a 2-pass + * color quantization; in that case, jinit_d_post_controller did not + * allocate a strip buffer. Use the virtual-array buffer as workspace. + */ + if (post->buffer == NULL) { + post->buffer = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, post->whole_image, + (JDIMENSION) 0, post->strip_height, TRUE); + } + } else { + /* For single-pass processing without color quantization, + * I have no work to do; just call the upsampler directly. + */ + post->pub.post_process_data = cinfo->upsample->upsample; + } + break; +#ifdef QUANT_2PASS_SUPPORTED + case JBUF_SAVE_AND_PASS: + /* First pass of 2-pass quantization */ + if (post->whole_image == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + post->pub.post_process_data = post_process_prepass; + break; + case JBUF_CRANK_DEST: + /* Second pass of 2-pass quantization */ + if (post->whole_image == NULL) + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + post->pub.post_process_data = post_process_2pass; + break; +#endif /* QUANT_2PASS_SUPPORTED */ + default: + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); + break; + } + post->starting_row = post->next_row = 0; +} + + +/* + * Process some data in the one-pass (strip buffer) case. + * This is used for color precision reduction as well as one-pass quantization. + */ + +METHODDEF(void) +post_process_1pass (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + my_post_ptr post = (my_post_ptr) cinfo->post; + JDIMENSION num_rows, max_rows; + + /* Fill the buffer, but not more than what we can dump out in one go. */ + /* Note we rely on the upsampler to detect bottom of image. */ + max_rows = out_rows_avail - *out_row_ctr; + if (max_rows > post->strip_height) + max_rows = post->strip_height; + num_rows = 0; + (*cinfo->upsample->upsample) (cinfo, + input_buf, in_row_group_ctr, in_row_groups_avail, + post->buffer, &num_rows, max_rows); + /* Quantize and emit data. */ + (*cinfo->cquantize->color_quantize) (cinfo, + post->buffer, output_buf + *out_row_ctr, (int) num_rows); + *out_row_ctr += num_rows; +} + + +#ifdef QUANT_2PASS_SUPPORTED + +/* + * Process some data in the first pass of 2-pass quantization. + */ + +METHODDEF(void) +post_process_prepass (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + my_post_ptr post = (my_post_ptr) cinfo->post; + JDIMENSION old_next_row, num_rows; + (void)output_buf;(void)out_rows_avail; + + /* Reposition virtual buffer if at start of strip. */ + if (post->next_row == 0) { + post->buffer = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, post->whole_image, + post->starting_row, post->strip_height, TRUE); + } + + /* Upsample some data (up to a strip height's worth). */ + old_next_row = post->next_row; + (*cinfo->upsample->upsample) (cinfo, + input_buf, in_row_group_ctr, in_row_groups_avail, + post->buffer, &post->next_row, post->strip_height); + + /* Allow quantizer to scan new data. No data is emitted, */ + /* but we advance out_row_ctr so outer loop can tell when we're done. */ + if (post->next_row > old_next_row) { + num_rows = post->next_row - old_next_row; + (*cinfo->cquantize->color_quantize) (cinfo, post->buffer + old_next_row, + (JSAMPARRAY) NULL, (int) num_rows); + *out_row_ctr += num_rows; + } + + /* Advance if we filled the strip. */ + if (post->next_row >= post->strip_height) { + post->starting_row += post->strip_height; + post->next_row = 0; + } +} + + +/* + * Process some data in the second pass of 2-pass quantization. + */ + +METHODDEF(void) +post_process_2pass (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + my_post_ptr post = (my_post_ptr) cinfo->post; + JDIMENSION num_rows, max_rows; + (void)input_buf;(void)in_row_group_ctr;(void)in_row_groups_avail; + + /* Reposition virtual buffer if at start of strip. */ + if (post->next_row == 0) { + post->buffer = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, post->whole_image, + post->starting_row, post->strip_height, FALSE); + } + + /* Determine number of rows to emit. */ + num_rows = post->strip_height - post->next_row; /* available in strip */ + max_rows = out_rows_avail - *out_row_ctr; /* available in output area */ + if (num_rows > max_rows) + num_rows = max_rows; + /* We have to check bottom of image here, can't depend on upsampler. */ + max_rows = cinfo->output_height - post->starting_row; + if (num_rows > max_rows) + num_rows = max_rows; + + /* Quantize and emit data. */ + (*cinfo->cquantize->color_quantize) (cinfo, + post->buffer + post->next_row, output_buf + *out_row_ctr, + (int) num_rows); + *out_row_ctr += num_rows; + + /* Advance if we filled the strip. */ + post->next_row += num_rows; + if (post->next_row >= post->strip_height) { + post->starting_row += post->strip_height; + post->next_row = 0; + } +} + +#endif /* QUANT_2PASS_SUPPORTED */ + + +/* + * Initialize postprocessing controller. + */ + +GLOBAL(void) +jinit_d_post_controller (j_decompress_ptr cinfo, boolean need_full_buffer) +{ + my_post_ptr post; + + post = (my_post_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_post_controller)); + cinfo->post = (struct jpeg_d_post_controller *) post; + post->pub.start_pass = start_pass_dpost; + post->whole_image = NULL; /* flag for no virtual arrays */ + post->buffer = NULL; /* flag for no strip buffer */ + + /* Create the quantization buffer, if needed */ + if (cinfo->quantize_colors) { + /* The buffer strip height is max_v_samp_factor, which is typically + * an efficient number of rows for upsampling to return. + * (In the presence of output rescaling, we might want to be smarter?) + */ + post->strip_height = (JDIMENSION) cinfo->max_v_samp_factor; + if (need_full_buffer) { + /* Two-pass color quantization: need full-image storage. */ + /* We round up the number of rows to a multiple of the strip height. */ +#ifdef QUANT_2PASS_SUPPORTED + post->whole_image = (*cinfo->mem->request_virt_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, + cinfo->output_width * cinfo->out_color_components, + (JDIMENSION) jround_up((long) cinfo->output_height, + (long) post->strip_height), + post->strip_height); +#else + ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); +#endif /* QUANT_2PASS_SUPPORTED */ + } else { + /* One-pass color quantization: just make a strip buffer. */ + post->buffer = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + cinfo->output_width * cinfo->out_color_components, + post->strip_height); + } + } +} diff --git a/src/gdcmjpeg/jdpred.c b/src/gdcmjpeg/jdpred.c new file mode 100644 index 00000000..4704fc4f --- /dev/null +++ b/src/gdcmjpeg/jdpred.c @@ -0,0 +1,258 @@ +/* + * jdpred.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains sample undifferencing (reconstruction) for lossless JPEG. + * + * In order to avoid paying the performance penalty of having to check the + * predictor being used and the row being processed for each call of the + * undifferencer, and to promote optimization, we have separate undifferencing + * functions for each case. + * + * We are able to avoid duplicating source code by implementing the predictors + * and undifferencers as macros. Each of the undifferencing functions are + * simply wrappers around an UNDIFFERENCE macro with the appropriate PREDICTOR + * macro passed as an argument. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ + + +#ifdef D_LOSSLESS_SUPPORTED + +/* Predictor for the first column of the first row: 2^(P-Pt-1) */ +#define INITIAL_PREDICTORx (1 << (cinfo->data_precision - cinfo->Al - 1)) + +/* Predictor for the first column of the remaining rows: Rb */ +#define INITIAL_PREDICTOR2 GETJSAMPLE(prev_row[0]) + + +/* + * 1-Dimensional undifferencer routine. + * + * This macro implements the 1-D horizontal predictor (1). INITIAL_PREDICTOR + * is used as the special case predictor for the first column, which must be + * either INITIAL_PREDICTOR2 or INITIAL_PREDICTORx. The remaining samples + * use PREDICTOR1. + * + * The reconstructed sample is supposed to be calculated modulo 2^16, so we + * logically AND the result with 0xFFFF. +*/ + +#define UNDIFFERENCE_1D(INITIAL_PREDICTOR) \ + unsigned int xindex; \ + int Ra; \ + \ + Ra = (diff_buf[0] + INITIAL_PREDICTOR) & 0xFFFF; \ + undiff_buf[0] = Ra; \ + \ + for (xindex = 1; xindex < width; xindex++) { \ + Ra = (diff_buf[xindex] + PREDICTOR1) & 0xFFFF; \ + undiff_buf[xindex] = Ra; \ + } + +/* + * 2-Dimensional undifferencer routine. + * + * This macro implements the 2-D horizontal predictors (#2-7). PREDICTOR2 is + * used as the special case predictor for the first column. The remaining + * samples use PREDICTOR, which is a function of Ra, Rb, Rc. + * + * Because prev_row and output_buf may point to the same storage area (in an + * interleaved image with Vi=1, for example), we must take care to buffer Rb/Rc + * before writing the current reconstructed sample value into output_buf. + * + * The reconstructed sample is supposed to be calculated modulo 2^16, so we + * logically AND the result with 0xFFFF. + */ + +#define UNDIFFERENCE_2D(PREDICTOR) \ + unsigned int xindex; \ + int Ra, Rb, Rc; \ + \ + Rb = GETJSAMPLE(prev_row[0]); \ + Ra = (diff_buf[0] + PREDICTOR2) & 0xFFFF; \ + undiff_buf[0] = Ra; \ + \ + for (xindex = 1; xindex < width; xindex++) { \ + Rc = Rb; \ + Rb = GETJSAMPLE(prev_row[xindex]); \ + Ra = (diff_buf[xindex] + PREDICTOR) & 0xFFFF; \ + undiff_buf[xindex] = Ra; \ + } + + +/* + * Undifferencers for the all rows but the first in a scan or restart interval. + * The first sample in the row is undifferenced using the vertical + * predictor (2). The rest of the samples are undifferenced using the + * predictor specified in the scan header. + */ + +METHODDEF(void) +jpeg_undifference1(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + UNDIFFERENCE_1D(INITIAL_PREDICTOR2); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + +METHODDEF(void) +jpeg_undifference2(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + UNDIFFERENCE_2D(PREDICTOR2); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + +METHODDEF(void) +jpeg_undifference3(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + UNDIFFERENCE_2D(PREDICTOR3); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + +METHODDEF(void) +jpeg_undifference4(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + UNDIFFERENCE_2D(PREDICTOR4); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + +METHODDEF(void) +jpeg_undifference5(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + SHIFT_TEMPS + UNDIFFERENCE_2D(PREDICTOR5); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + +METHODDEF(void) +jpeg_undifference6(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + SHIFT_TEMPS + UNDIFFERENCE_2D(PREDICTOR6); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + +METHODDEF(void) +jpeg_undifference7(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + SHIFT_TEMPS + UNDIFFERENCE_2D(PREDICTOR7); + (void)cinfo;(void)comp_index;(void)diff_buf;(void)prev_row;(void)undiff_buf;(void)width; +} + + +/* + * Undifferencer for the first row in a scan or restart interval. The first + * sample in the row is undifferenced using the special predictor constant + * x=2^(P-Pt-1). The rest of the samples are undifferenced using the + * 1-D horizontal predictor (1). + */ + +METHODDEF(void) +jpeg_undifference_first_row(j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + + UNDIFFERENCE_1D(INITIAL_PREDICTORx); + (void)prev_row; + + /* + * Now that we have undifferenced the first row, we want to use the + * undifferencer which corresponds to the predictor specified in the + * scan header. + */ + switch (cinfo->Ss) { + case 1: + losslsd->predict_undifference[comp_index] = jpeg_undifference1; + break; + case 2: + losslsd->predict_undifference[comp_index] = jpeg_undifference2; + break; + case 3: + losslsd->predict_undifference[comp_index] = jpeg_undifference3; + break; + case 4: + losslsd->predict_undifference[comp_index] = jpeg_undifference4; + break; + case 5: + losslsd->predict_undifference[comp_index] = jpeg_undifference5; + break; + case 6: + losslsd->predict_undifference[comp_index] = jpeg_undifference6; + break; + case 7: + losslsd->predict_undifference[comp_index] = jpeg_undifference7; + break; + } +} + + +/* + * Initialize for an input processing pass. + */ + +METHODDEF(void) +predict_start_pass (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + int ci; + + /* Check that the scan parameters Ss, Se, Ah, Al are OK for lossless JPEG. + * + * Ss is the predictor selection value (psv). Legal values for sequential + * lossless JPEG are: 1 <= psv <= 7. + * + * Se and Ah are not used and should be zero. + * + * Al specifies the point transform (Pt). Legal values are: 0 <= Pt <= 15. + */ + if (cinfo->Ss < 1 || cinfo->Ss > 7 || + cinfo->Se != 0 || cinfo->Ah != 0 || + cinfo->Al > 15) /* need not check for < 0 */ + ERREXIT4(cinfo, JERR_BAD_LOSSLESS, + cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al); + + /* Set undifference functions to first row function */ + for (ci = 0; ci < cinfo->num_components; ci++) + losslsd->predict_undifference[ci] = jpeg_undifference_first_row; +} + + +/* + * Module initialization routine for the undifferencer. + */ + +GLOBAL(void) +jinit_undifferencer (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + + losslsd->predict_start_pass = predict_start_pass; + losslsd->predict_process_restart = predict_start_pass; +} + +#endif /* D_LOSSLESS_SUPPORTED */ + diff --git a/src/gdcmjpeg/jdsample.c b/src/gdcmjpeg/jdsample.c new file mode 100644 index 00000000..a36283e2 --- /dev/null +++ b/src/gdcmjpeg/jdsample.c @@ -0,0 +1,483 @@ +/* + * jdsample.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains upsampling routines. + * + * Upsampling input data is counted in "row groups". A row group + * is defined to be (v_samp_factor * codec_data_unit / min_codec_data_unit) + * sample rows of each component. Upsampling will normally produce + * max_v_samp_factor pixel rows from each row group (but this could vary + * if the upsampler is applying a scale factor of its own). + * + * An excellent reference for image resampling is + * Digital Image Warping, George Wolberg, 1990. + * Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Pointer to routine to upsample a single component */ +typedef JMETHOD(void, upsample1_ptr, + (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)); + +/* Private subobject */ + +typedef struct { + struct jpeg_upsampler pub; /* public fields */ + + /* Color conversion buffer. When using separate upsampling and color + * conversion steps, this buffer holds one upsampled row group until it + * has been color converted and output. + * Note: we do not allocate any storage for component(s) which are full-size, + * ie do not need rescaling. The corresponding entry of color_buf[] is + * simply set to point to the input data array, thereby avoiding copying. + */ + JSAMPARRAY color_buf[MAX_COMPONENTS]; + + /* Per-component upsampling method pointers */ + upsample1_ptr methods[MAX_COMPONENTS]; + + int next_row_out; /* counts rows emitted from color_buf */ + JDIMENSION rows_to_go; /* counts rows remaining in image */ + + /* Height of an input row group for each component. */ + int rowgroup_height[MAX_COMPONENTS]; + + /* These arrays save pixel expansion factors so that int_expand need not + * recompute them each time. They are unused for other upsampling methods. + */ + UINT8 h_expand[MAX_COMPONENTS]; + UINT8 v_expand[MAX_COMPONENTS]; +} my_upsampler; + +typedef my_upsampler * my_upsample_ptr; + + +/* + * Initialize for an upsampling pass. + */ + +METHODDEF(void) +start_pass_upsample (j_decompress_ptr cinfo) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + + /* Mark the conversion buffer empty */ + upsample->next_row_out = cinfo->max_v_samp_factor; + /* Initialize total-height counter for detecting bottom of image */ + upsample->rows_to_go = cinfo->output_height; +} + + +/* + * Control routine to do upsampling (and color conversion). + * + * In this version we upsample each component independently. + * We upsample one row group into the conversion buffer, then apply + * color conversion a row at a time. + */ + +METHODDEF(void) +sep_upsample (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + int ci; + jpeg_component_info * compptr; + JDIMENSION num_rows; + (void)in_row_groups_avail; + + /* Fill the conversion buffer, if it's empty */ + if (upsample->next_row_out >= cinfo->max_v_samp_factor) { + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Invoke per-component upsample method. Notice we pass a POINTER + * to color_buf[ci], so that fullsize_upsample can change it. + */ + (*upsample->methods[ci]) (cinfo, compptr, + input_buf[ci] + (*in_row_group_ctr * upsample->rowgroup_height[ci]), + upsample->color_buf + ci); + } + upsample->next_row_out = 0; + } + + /* Color-convert and emit rows */ + + /* How many we have in the buffer: */ + num_rows = (JDIMENSION) (cinfo->max_v_samp_factor - upsample->next_row_out); + /* Not more than the distance to the end of the image. Need this test + * in case the image height is not a multiple of max_v_samp_factor: + */ + if (num_rows > upsample->rows_to_go) + num_rows = upsample->rows_to_go; + /* And not more than what the client can accept: */ + out_rows_avail -= *out_row_ctr; + if (num_rows > out_rows_avail) + num_rows = out_rows_avail; + + (*cinfo->cconvert->color_convert) (cinfo, upsample->color_buf, + (JDIMENSION) upsample->next_row_out, + output_buf + *out_row_ctr, + (int) num_rows); + + /* Adjust counts */ + *out_row_ctr += num_rows; + upsample->rows_to_go -= num_rows; + upsample->next_row_out += num_rows; + /* When the buffer is emptied, declare this input row group consumed */ + if (upsample->next_row_out >= cinfo->max_v_samp_factor) + (*in_row_group_ctr)++; +} + + +/* + * These are the routines invoked by sep_upsample to upsample pixel values + * of a single component. One row group is processed per call. + */ + + +/* + * For full-size components, we just make color_buf[ci] point at the + * input buffer, and thus avoid copying any data. Note that this is + * safe only because sep_upsample doesn't declare the input row group + * "consumed" until we are done color converting and emitting it. + */ + +METHODDEF(void) +fullsize_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + (void)cinfo;(void)compptr; + *output_data_ptr = input_data; +} + + +/* + * This is a no-op version used for "uninteresting" components. + * These components will not be referenced by color conversion. + */ + +METHODDEF(void) +noop_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + (void)cinfo;(void)compptr;(void)input_data; + *output_data_ptr = NULL; /* safety check */ +} + + +/* + * This version handles any integral sampling ratios. + * This is not used for typical JPEG files, so it need not be fast. + * Nor, for that matter, is it particularly accurate: the algorithm is + * simple replication of the input pixel onto the corresponding output + * pixels. The hi-falutin sampling literature refers to this as a + * "box filter". A box filter tends to introduce visible artifacts, + * so if you are actually going to use 3:1 or 4:1 sampling ratios + * you would be well advised to improve this code. + */ + +METHODDEF(void) +int_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + JSAMPARRAY output_data = *output_data_ptr; + register JSAMPROW inptr, outptr; + register JSAMPLE invalue; + register int h; + JSAMPROW outend; + int h_expand, v_expand; + int inrow, outrow; + + h_expand = upsample->h_expand[compptr->component_index]; + v_expand = upsample->v_expand[compptr->component_index]; + + inrow = outrow = 0; + while (outrow < cinfo->max_v_samp_factor) { + /* Generate one output row with proper horizontal expansion */ + inptr = input_data[inrow]; + outptr = output_data[outrow]; + outend = outptr + cinfo->output_width; + while (outptr < outend) { + invalue = *inptr++; /* don't need GETJSAMPLE() here */ + for (h = h_expand; h > 0; h--) { + *outptr++ = invalue; + } + } + /* Generate any additional output rows by duplicating the first one */ + if (v_expand > 1) { + jcopy_sample_rows(output_data, outrow, output_data, outrow+1, + v_expand-1, cinfo->output_width); + } + inrow++; + outrow += v_expand; + } +} + + +/* + * Fast processing for the common case of 2:1 horizontal and 1:1 vertical. + * It's still a box filter. + */ + +METHODDEF(void) +h2v1_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + JSAMPARRAY output_data = *output_data_ptr; + register JSAMPROW inptr, outptr; + register JSAMPLE invalue; + JSAMPROW outend; + int inrow; + (void)compptr; + + for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) { + inptr = input_data[inrow]; + outptr = output_data[inrow]; + outend = outptr + cinfo->output_width; + while (outptr < outend) { + invalue = *inptr++; /* don't need GETJSAMPLE() here */ + *outptr++ = invalue; + *outptr++ = invalue; + } + } +} + + +/* + * Fast processing for the common case of 2:1 horizontal and 2:1 vertical. + * It's still a box filter. + */ + +METHODDEF(void) +h2v2_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + JSAMPARRAY output_data = *output_data_ptr; + register JSAMPROW inptr, outptr; + register JSAMPLE invalue; + JSAMPROW outend; + int inrow, outrow; + (void)compptr; + + inrow = outrow = 0; + while (outrow < cinfo->max_v_samp_factor) { + inptr = input_data[inrow]; + outptr = output_data[outrow]; + outend = outptr + cinfo->output_width; + while (outptr < outend) { + invalue = *inptr++; /* don't need GETJSAMPLE() here */ + *outptr++ = invalue; + *outptr++ = invalue; + } + jcopy_sample_rows(output_data, outrow, output_data, outrow+1, + 1, cinfo->output_width); + inrow++; + outrow += 2; + } +} + + +/* + * Fancy processing for the common case of 2:1 horizontal and 1:1 vertical. + * + * The upsampling algorithm is linear interpolation between pixel centers, + * also known as a "triangle filter". This is a good compromise between + * speed and visual quality. The centers of the output pixels are 1/4 and 3/4 + * of the way between input pixel centers. + * + * A note about the "bias" calculations: when rounding fractional values to + * integer, we do not want to always round 0.5 up to the next integer. + * If we did that, we'd introduce a noticeable bias towards larger values. + * Instead, this code is arranged so that 0.5 will be rounded up or down at + * alternate pixel locations (a simple ordered dither pattern). + */ + +METHODDEF(void) +h2v1_fancy_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + JSAMPARRAY output_data = *output_data_ptr; + register JSAMPROW inptr, outptr; + register int invalue; + register JDIMENSION colctr; + int inrow; + + for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) { + inptr = input_data[inrow]; + outptr = output_data[inrow]; + /* Special case for first column */ + invalue = GETJSAMPLE(*inptr++); + *outptr++ = (JSAMPLE) invalue; + *outptr++ = (JSAMPLE) ((invalue * 3 + GETJSAMPLE(*inptr) + 2) >> 2); + + for (colctr = compptr->downsampled_width - 2; colctr > 0; colctr--) { + /* General case: 3/4 * nearer pixel + 1/4 * further pixel */ + invalue = GETJSAMPLE(*inptr++) * 3; + *outptr++ = (JSAMPLE) ((invalue + GETJSAMPLE(inptr[-2]) + 1) >> 2); + *outptr++ = (JSAMPLE) ((invalue + GETJSAMPLE(*inptr) + 2) >> 2); + } + + /* Special case for last column */ + invalue = GETJSAMPLE(*inptr); + *outptr++ = (JSAMPLE) ((invalue * 3 + GETJSAMPLE(inptr[-1]) + 1) >> 2); + *outptr++ = (JSAMPLE) invalue; + } +} + + +/* + * Fancy processing for the common case of 2:1 horizontal and 2:1 vertical. + * Again a triangle filter; see comments for h2v1 case, above. + * + * It is OK for us to reference the adjacent input rows because we demanded + * context from the main buffer controller (see initialization code). + */ + +METHODDEF(void) +h2v2_fancy_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ + JSAMPARRAY output_data = *output_data_ptr; + register JSAMPROW inptr0, inptr1, outptr; +#if BITS_IN_JSAMPLE == 8 + register int thiscolsum, lastcolsum, nextcolsum; +#else + register INT32 thiscolsum, lastcolsum, nextcolsum; +#endif + register JDIMENSION colctr; + int inrow, outrow, v; + + inrow = outrow = 0; + while (outrow < cinfo->max_v_samp_factor) { + for (v = 0; v < 2; v++) { + /* inptr0 points to nearest input row, inptr1 points to next nearest */ + inptr0 = input_data[inrow]; + if (v == 0) /* next nearest is row above */ + inptr1 = input_data[inrow-1]; + else /* next nearest is row below */ + inptr1 = input_data[inrow+1]; + outptr = output_data[outrow++]; + + /* Special case for first column */ + thiscolsum = GETJSAMPLE(*inptr0++) * 3 + GETJSAMPLE(*inptr1++); + nextcolsum = GETJSAMPLE(*inptr0++) * 3 + GETJSAMPLE(*inptr1++); + *outptr++ = (JSAMPLE) ((thiscolsum * 4 + 8) >> 4); + *outptr++ = (JSAMPLE) ((thiscolsum * 3 + nextcolsum + 7) >> 4); + lastcolsum = thiscolsum; thiscolsum = nextcolsum; + + for (colctr = compptr->downsampled_width - 2; colctr > 0; colctr--) { + /* General case: 3/4 * nearer pixel + 1/4 * further pixel in each */ + /* dimension, thus 9/16, 3/16, 3/16, 1/16 overall */ + nextcolsum = GETJSAMPLE(*inptr0++) * 3 + GETJSAMPLE(*inptr1++); + *outptr++ = (JSAMPLE) ((thiscolsum * 3 + lastcolsum + 8) >> 4); + *outptr++ = (JSAMPLE) ((thiscolsum * 3 + nextcolsum + 7) >> 4); + lastcolsum = thiscolsum; thiscolsum = nextcolsum; + } + + /* Special case for last column */ + *outptr++ = (JSAMPLE) ((thiscolsum * 3 + lastcolsum + 8) >> 4); + *outptr++ = (JSAMPLE) ((thiscolsum * 4 + 7) >> 4); + } + inrow++; + } +} + + +/* + * Module initialization routine for upsampling. + */ + +GLOBAL(void) +jinit_upsampler (j_decompress_ptr cinfo) +{ + my_upsample_ptr upsample; + int ci; + jpeg_component_info * compptr; + boolean need_buffer, do_fancy; + int h_in_group, v_in_group, h_out_group, v_out_group; + + upsample = (my_upsample_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_upsampler)); + cinfo->upsample = (struct jpeg_upsampler *) upsample; + upsample->pub.start_pass = start_pass_upsample; + upsample->pub.upsample = sep_upsample; + upsample->pub.need_context_rows = FALSE; /* until we find out differently */ + + if (cinfo->CCIR601_sampling) /* this isn't supported */ + ERREXIT(cinfo, JERR_CCIR601_NOTIMPL); + + /* jdmainct.c doesn't support context rows when min_codec_data_unit = 1, + * so don't ask for it. + */ + do_fancy = cinfo->do_fancy_upsampling && cinfo->min_codec_data_unit > 1; + + /* Verify we can handle the sampling factors, select per-component methods, + * and create storage as needed. + */ + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + /* Compute size of an "input group" after IDCT scaling. This many samples + * are to be converted to max_h_samp_factor * max_v_samp_factor pixels. + */ + h_in_group = (compptr->h_samp_factor * compptr->codec_data_unit) / + cinfo->min_codec_data_unit; + v_in_group = (compptr->v_samp_factor * compptr->codec_data_unit) / + cinfo->min_codec_data_unit; + h_out_group = cinfo->max_h_samp_factor; + v_out_group = cinfo->max_v_samp_factor; + upsample->rowgroup_height[ci] = v_in_group; /* save for use later */ + need_buffer = TRUE; + if (! compptr->component_needed) { + /* Don't bother to upsample an uninteresting component. */ + upsample->methods[ci] = noop_upsample; + need_buffer = FALSE; + } else if (h_in_group == h_out_group && v_in_group == v_out_group) { + /* Fullsize components can be processed without any work. */ + upsample->methods[ci] = fullsize_upsample; + need_buffer = FALSE; + } else if (h_in_group * 2 == h_out_group && + v_in_group == v_out_group) { + /* Special cases for 2h1v upsampling */ + if (do_fancy && compptr->downsampled_width > 2) + upsample->methods[ci] = h2v1_fancy_upsample; + else + upsample->methods[ci] = h2v1_upsample; + } else if (h_in_group * 2 == h_out_group && + v_in_group * 2 == v_out_group) { + /* Special cases for 2h2v upsampling */ + if (do_fancy && compptr->downsampled_width > 2) { + upsample->methods[ci] = h2v2_fancy_upsample; + upsample->pub.need_context_rows = TRUE; + } else + upsample->methods[ci] = h2v2_upsample; + } else if ((h_out_group % h_in_group) == 0 && + (v_out_group % v_in_group) == 0) { + /* Generic integral-factors upsampling method */ + upsample->methods[ci] = int_upsample; + upsample->h_expand[ci] = (UINT8) (h_out_group / h_in_group); + upsample->v_expand[ci] = (UINT8) (v_out_group / v_in_group); + } else + ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL); + if (need_buffer) { + upsample->color_buf[ci] = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) jround_up((long) cinfo->output_width, + (long) cinfo->max_h_samp_factor), + (JDIMENSION) cinfo->max_v_samp_factor); + } + } +} diff --git a/src/gdcmjpeg/jdscale.c b/src/gdcmjpeg/jdscale.c new file mode 100644 index 00000000..9cdd9b72 --- /dev/null +++ b/src/gdcmjpeg/jdscale.c @@ -0,0 +1,120 @@ +/* + * jdscale.c + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains sample scaling for lossless JPEG. This is a + * combination of upscaling the undifferenced sample by 2^Pt and downscaling + * the sample to fit into JSAMPLE. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossls.h" /* Private declarations for lossless codec */ + + +#ifdef D_LOSSLESS_SUPPORTED + +/* + * Private scaler object for lossless decoding. + */ + +typedef struct { + int scale_factor; +} scaler; + +typedef scaler * scaler_ptr; + + +/* + * Scalers for packing sample differences into JSAMPLEs. + */ + +METHODDEF(void) +simple_upscale(j_decompress_ptr cinfo, + JDIFFROW diff_buf, JSAMPROW output_buf, + JDIMENSION width) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + scaler_ptr scaler = (scaler_ptr) losslsd->scaler_private; + int scale_factor = scaler->scale_factor; + unsigned int xindex; + + for (xindex = 0; xindex < width; xindex++) + output_buf[xindex] = (JSAMPLE) (diff_buf[xindex] << scale_factor); +} + +METHODDEF(void) +simple_downscale(j_decompress_ptr cinfo, + JDIFFROW diff_buf, JSAMPROW output_buf, + JDIMENSION width) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + scaler_ptr scaler = (scaler_ptr) losslsd->scaler_private; + int scale_factor = scaler->scale_factor; + unsigned int xindex; + SHIFT_TEMPS + + for (xindex = 0; xindex < width; xindex++) + output_buf[xindex] = (JSAMPLE) RIGHT_SHIFT(diff_buf[xindex], scale_factor); +} + +METHODDEF(void) +noscale(j_decompress_ptr cinfo, + JDIFFROW diff_buf, JSAMPROW output_buf, + JDIMENSION width) +{ + unsigned int xindex; + (void)cinfo; + + for (xindex = 0; xindex < width; xindex++) + output_buf[xindex] = (JSAMPLE) diff_buf[xindex]; +} + + +METHODDEF(void) +scaler_start_pass (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + scaler_ptr scaler = (scaler_ptr) losslsd->scaler_private; + int downscale; + + /* + * Downscale by the difference in the input vs. output precision. If the + * output precision >= input precision, then do not downscale. + */ + downscale = BITS_IN_JSAMPLE < cinfo->data_precision ? + cinfo->data_precision - BITS_IN_JSAMPLE : 0; + + scaler->scale_factor = cinfo->Al - downscale; + + /* Set scaler functions based on scale_factor (positive = left shift) */ + if (scaler->scale_factor > 0) + losslsd->scaler_scale = simple_upscale; + else if (scaler->scale_factor < 0) { + scaler->scale_factor = -scaler->scale_factor; + losslsd->scaler_scale = simple_downscale; + } + else + losslsd->scaler_scale = noscale; +} + + +GLOBAL(void) +jinit_d_scaler (j_decompress_ptr cinfo) +{ + j_lossless_d_ptr losslsd = (j_lossless_d_ptr) cinfo->codec; + scaler_ptr scaler; + + scaler = (scaler_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(scaler)); + losslsd->scaler_private = (void *) scaler; + losslsd->scaler_start_pass = scaler_start_pass; +} + +#endif /* D_LOSSLESS_SUPPORTED */ + diff --git a/src/gdcmjpeg/jdshuff.c b/src/gdcmjpeg/jdshuff.c new file mode 100644 index 00000000..326220c4 --- /dev/null +++ b/src/gdcmjpeg/jdshuff.c @@ -0,0 +1,360 @@ +/* + * jdshuff.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains Huffman entropy decoding routines for sequential JPEG. + * + * Much of the complexity here has to do with supporting input suspension. + * If the data source module demands suspension, we want to be able to back + * up to the start of the current MCU. To do this, we copy state variables + * into local working storage, and update them back to the permanent + * storage only upon successful completion of an MCU. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" /* Private declarations for lossy codec */ +#include "jdhuff.h" /* Declarations shared with jd*huff.c */ + + +/* + * Private entropy decoder object for Huffman decoding. + * + * The savable_state subrecord contains fields that change within an MCU, + * but must not be updated permanently until we complete the MCU. + */ + +typedef struct { + int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */ +} savable_state; + +/* This macro is to work around compilers with missing or broken + * structure assignment. You'll need to fix this code if you have + * such a compiler and you change MAX_COMPS_IN_SCAN. + */ + +#ifndef NO_STRUCT_ASSIGN +#define ASSIGN_STATE(dest,src) ((dest) = (src)) +#else +#if MAX_COMPS_IN_SCAN == 4 +#define ASSIGN_STATE(dest,src) \ + ((dest).last_dc_val[0] = (src).last_dc_val[0], \ + (dest).last_dc_val[1] = (src).last_dc_val[1], \ + (dest).last_dc_val[2] = (src).last_dc_val[2], \ + (dest).last_dc_val[3] = (src).last_dc_val[3]) +#endif +#endif + + +typedef struct { + huffd_common_fields; /* Fields shared with other entropy decoders */ + + /* These fields are loaded into local variables at start of each MCU. + * In case of suspension, we exit WITHOUT updating them. + */ + savable_state saved; /* Other state at start of MCU */ + + /* These fields are NOT loaded into local working state. */ + unsigned int restarts_to_go; /* MCUs left in this restart interval */ + + /* Pointers to derived tables (these workspaces have image lifespan) */ + d_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS]; + d_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS]; + + /* Precalculated info set up by start_pass for use in decode_mcu: */ + + /* Pointers to derived tables to be used for each block within an MCU */ + d_derived_tbl * dc_cur_tbls[D_MAX_DATA_UNITS_IN_MCU]; + d_derived_tbl * ac_cur_tbls[D_MAX_DATA_UNITS_IN_MCU]; + /* Whether we care about the DC and AC coefficient values for each block */ + boolean dc_needed[D_MAX_DATA_UNITS_IN_MCU]; + boolean ac_needed[D_MAX_DATA_UNITS_IN_MCU]; +} shuff_entropy_decoder; + +typedef shuff_entropy_decoder * shuff_entropy_ptr; + + +/* + * Initialize for a Huffman-compressed scan. + */ + +METHODDEF(void) +start_pass_huff_decoder (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyd->entropy_private; + int ci, blkn, dctbl, actbl; + jpeg_component_info * compptr; + + /* Check that the scan parameters Ss, Se, Ah/Al are OK for sequential JPEG. + * This ought to be an error condition, but we make it a warning because + * there are some baseline files out there with all zeroes in these bytes. + */ + if (cinfo->Ss != 0 || cinfo->Se != DCTSIZE2-1 || + cinfo->Ah != 0 || cinfo->Al != 0) + WARNMS(cinfo, JWRN_NOT_SEQUENTIAL); + + for (ci = 0; ci < cinfo->comps_in_scan; ci++) { + compptr = cinfo->cur_comp_info[ci]; + dctbl = compptr->dc_tbl_no; + actbl = compptr->ac_tbl_no; + /* Compute derived values for Huffman tables */ + /* We may do this more than once for a table, but it's not expensive */ + jpeg_make_d_derived_tbl(cinfo, TRUE, dctbl, + & entropy->dc_derived_tbls[dctbl]); + jpeg_make_d_derived_tbl(cinfo, FALSE, actbl, + & entropy->ac_derived_tbls[actbl]); + /* Initialize DC predictions to 0 */ + entropy->saved.last_dc_val[ci] = 0; + } + + /* Precalculate decoding info for each block in an MCU of this scan */ + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + ci = cinfo->MCU_membership[blkn]; + compptr = cinfo->cur_comp_info[ci]; + /* Precalculate which table to use for each block */ + entropy->dc_cur_tbls[blkn] = entropy->dc_derived_tbls[compptr->dc_tbl_no]; + entropy->ac_cur_tbls[blkn] = entropy->ac_derived_tbls[compptr->ac_tbl_no]; + /* Decide whether we really care about the coefficient values */ + if (compptr->component_needed) { + entropy->dc_needed[blkn] = TRUE; + /* we don't need the ACs if producing a 1/8th-size image */ + entropy->ac_needed[blkn] = (compptr->codec_data_unit > 1); + } else { + entropy->dc_needed[blkn] = entropy->ac_needed[blkn] = FALSE; + } + } + + /* Initialize bitread state variables */ + entropy->bitstate.bits_left = 0; + entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */ + entropy->insufficient_data = FALSE; + + /* Initialize restart counter */ + entropy->restarts_to_go = cinfo->restart_interval; +} + + +/* + * Figure F.12: extend sign bit. + * On some machines, a shift and add will be faster than a table lookup. + */ + +#ifdef AVOID_TABLES + +#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x)) + +#else + +#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x)) + +static const int extend_test[16] = /* entry n is 2**(n-1) */ + { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, + 0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 }; + +static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */ + { 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1, + ((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1, + ((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1, + ((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 }; + +#endif /* AVOID_TABLES */ + + +/* + * Check for a restart marker & resynchronize decoder. + * Returns FALSE if must suspend. + */ + +LOCAL(boolean) +process_restart (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyd->entropy_private; + int ci; + + /* Throw away any unused bits remaining in bit buffer; */ + /* include any full bytes in next_marker's count of discarded bytes */ + cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8; + entropy->bitstate.bits_left = 0; + + /* Advance past the RSTn marker */ + if (! (*cinfo->marker->read_restart_marker) (cinfo)) + return FALSE; + + /* Re-initialize DC predictions to 0 */ + for (ci = 0; ci < cinfo->comps_in_scan; ci++) + entropy->saved.last_dc_val[ci] = 0; + + /* Reset restart counter */ + entropy->restarts_to_go = cinfo->restart_interval; + + /* Reset out-of-data flag, unless read_restart_marker left us smack up + * against a marker. In that case we will end up treating the next data + * segment as empty, and we can avoid producing bogus output pixels by + * leaving the flag set. + */ + if (cinfo->unread_marker == 0) + entropy->insufficient_data = FALSE; + + return TRUE; +} + + +/* + * Decode and return one MCU's worth of Huffman-compressed coefficients. + * The coefficients are reordered from zigzag order into natural array order, + * but are not dequantized. + * + * The i'th block of the MCU is stored into the block pointed to by + * MCU_data[i]. WE ASSUME THIS AREA HAS BEEN ZEROED BY THE CALLER. + * (Wholesale zeroing is usually a little faster than retail...) + * + * Returns FALSE if data source requested suspension. In that case no + * changes have been made to permanent state. (Exception: some output + * coefficients may already have been assigned. This is harmless for + * this module, since we'll just re-assign them on the next call.) + */ + +METHODDEF(boolean) +decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + shuff_entropy_ptr entropy = (shuff_entropy_ptr) lossyd->entropy_private; + int blkn; + BITREAD_STATE_VARS; + savable_state state; + + /* Process restart marker if needed; may have to suspend */ + if (cinfo->restart_interval) { + if (entropy->restarts_to_go == 0) + if (! process_restart(cinfo)) + return FALSE; + } + + /* If we've run out of data, just leave the MCU set to zeroes. + * This way, we return uniform gray for the remainder of the segment. + */ + if (! entropy->insufficient_data) { + + /* Load up working state */ + BITREAD_LOAD_STATE(cinfo,entropy->bitstate); + ASSIGN_STATE(state, entropy->saved); + + /* Outer loop handles each block in the MCU */ + + for (blkn = 0; blkn < cinfo->data_units_in_MCU; blkn++) { + JBLOCKROW block = MCU_data[blkn]; + d_derived_tbl * dctbl = entropy->dc_cur_tbls[blkn]; + d_derived_tbl * actbl = entropy->ac_cur_tbls[blkn]; + register int s, k, r; + + /* Decode a single block's worth of coefficients */ + + /* Section F.2.2.1: decode the DC coefficient difference */ + HUFF_DECODE(s, br_state, dctbl, return FALSE, label1); + if (s) { + CHECK_BIT_BUFFER(br_state, s, return FALSE); + r = GET_BITS(s); + s = HUFF_EXTEND(r, s); + } + + if (entropy->dc_needed[blkn]) { + /* Convert DC difference to actual value, update last_dc_val */ + int ci = cinfo->MCU_membership[blkn]; + s += state.last_dc_val[ci]; + state.last_dc_val[ci] = s; + /* Output the DC coefficient (assumes jpeg_natural_order[0] = 0) */ + (*block)[0] = (JCOEF) s; + } + + if (entropy->ac_needed[blkn]) { + + /* Section F.2.2.2: decode the AC coefficients */ + /* Since zeroes are skipped, output area must be cleared beforehand */ + for (k = 1; k < DCTSIZE2; k++) { + HUFF_DECODE(s, br_state, actbl, return FALSE, label2); + + r = s >> 4; + s &= 15; + + if (s) { + k += r; + CHECK_BIT_BUFFER(br_state, s, return FALSE); + r = GET_BITS(s); + s = HUFF_EXTEND(r, s); + /* Output coefficient in natural (dezigzagged) order. + * Note: the extra entries in jpeg_natural_order[] will save us + * if k >= DCTSIZE2, which could happen if the data is corrupted. + */ + (*block)[jpeg_natural_order[k]] = (JCOEF) s; + } else { + if (r != 15) + break; + k += 15; + } + } + + } else { + + /* Section F.2.2.2: decode the AC coefficients */ + /* In this path we just discard the values */ + for (k = 1; k < DCTSIZE2; k++) { + HUFF_DECODE(s, br_state, actbl, return FALSE, label3); + + r = s >> 4; + s &= 15; + + if (s) { + k += r; + CHECK_BIT_BUFFER(br_state, s, return FALSE); + DROP_BITS(s); + } else { + if (r != 15) + break; + k += 15; + } + } + + } + } + + /* Completed MCU, so update state */ + BITREAD_SAVE_STATE(cinfo,entropy->bitstate); + ASSIGN_STATE(entropy->saved, state); + } + + /* Account for restart interval (no-op if not using restarts) */ + entropy->restarts_to_go--; + + return TRUE; +} + + +/* + * Module initialization routine for Huffman entropy decoding. + */ + +GLOBAL(void) +jinit_shuff_decoder (j_decompress_ptr cinfo) +{ + j_lossy_d_ptr lossyd = (j_lossy_d_ptr) cinfo->codec; + shuff_entropy_ptr entropy; + int i; + + entropy = (shuff_entropy_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(shuff_entropy_decoder)); + lossyd->entropy_private = (void *) entropy; + lossyd->entropy_start_pass = start_pass_huff_decoder; + lossyd->entropy_decode_mcu = decode_mcu; + + /* Mark tables unallocated */ + for (i = 0; i < NUM_HUFF_TBLS; i++) { + entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL; + } +} diff --git a/src/gdcmjpeg/jdtrans.c b/src/gdcmjpeg/jdtrans.c new file mode 100644 index 00000000..af35263c --- /dev/null +++ b/src/gdcmjpeg/jdtrans.c @@ -0,0 +1,138 @@ +/* + * jdtrans.c + * + * Copyright (C) 1995-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains library routines for transcoding decompression, + * that is, reading raw DCT coefficient arrays from an input JPEG file. + * The routines in jdapimin.c will also be needed by a transcoder. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jlossy.h" + + +/* Forward declarations */ +LOCAL(void) transdecode_master_selection JPP((j_decompress_ptr cinfo)); + + +/* + * Read the coefficient arrays from a JPEG file. + * jpeg_read_header must be completed before calling this. + * + * The entire image is read into a set of virtual coefficient-block arrays, + * one per component. The return value is a pointer to the array of + * virtual-array descriptors. These can be manipulated directly via the + * JPEG memory manager, or handed off to jpeg_write_coefficients(). + * To release the memory occupied by the virtual arrays, call + * jpeg_finish_decompress() when done with the data. + * + * An alternative usage is to simply obtain access to the coefficient arrays + * during a buffered-image-mode decompression operation. This is allowed + * after any jpeg_finish_output() call. The arrays can be accessed until + * jpeg_finish_decompress() is called. (Note that any call to the library + * may reposition the arrays, so don't rely on access_virt_barray() results + * to stay valid across library calls.) + * + * Returns NULL if suspended. This case need be checked only if + * a suspending data source is used. + */ + +GLOBAL(jvirt_barray_ptr *) +jpeg_read_coefficients (j_decompress_ptr cinfo) +{ + /* j_lossy_d_ptr decomp; */ + + /* Can't read coefficients from lossless streams */ + if (cinfo->process == JPROC_LOSSLESS) { + ERREXIT(cinfo, JERR_CANT_TRANSCODE); + return NULL; + } + + if (cinfo->global_state == DSTATE_READY) { + /* First call: initialize active modules */ + transdecode_master_selection(cinfo); + cinfo->global_state = DSTATE_RDCOEFS; + } + if (cinfo->global_state == DSTATE_RDCOEFS) { + /* Absorb whole file into the coef buffer */ + for (;;) { + int retcode; + /* Call progress monitor hook if present */ + if (cinfo->progress != NULL) + (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); + /* Absorb some more input */ + retcode = (*cinfo->inputctl->consume_input) (cinfo); + if (retcode == JPEG_SUSPENDED) + return NULL; + if (retcode == JPEG_REACHED_EOI) + break; + /* Advance progress counter if appropriate */ + if (cinfo->progress != NULL && + (retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) { + if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) { + /* startup underestimated number of scans; ratchet up one scan */ + cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows; + } + } + } + /* Set state so that jpeg_finish_decompress does the right thing */ + cinfo->global_state = DSTATE_STOPPING; + } + /* At this point we should be in state DSTATE_STOPPING if being used + * standalone, or in state DSTATE_BUFIMAGE if being invoked to get access + * to the coefficients during a full buffered-image-mode decompression. + */ + if ((cinfo->global_state == DSTATE_STOPPING || + cinfo->global_state == DSTATE_BUFIMAGE) && cinfo->buffered_image) { + return ((j_lossy_d_ptr) cinfo->codec)->coef_arrays; + } + /* Oops, improper usage */ + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); + return NULL; /* keep compiler happy */ +} + + +/* + * Master selection of decompression modules for transcoding. + * This substitutes for jdmaster.c's initialization of the full decompressor. + */ + +LOCAL(void) +transdecode_master_selection (j_decompress_ptr cinfo) +{ + /* This is effectively a buffered-image operation. */ + cinfo->buffered_image = TRUE; + + /* Initialize decompression codec */ + jinit_d_codec(cinfo); + + /* We can now tell the memory manager to allocate virtual arrays. */ + (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo); + + /* Initialize input side of decompressor to consume first scan. */ + (*cinfo->inputctl->start_input_pass) (cinfo); + + /* Initialize progress monitoring. */ + if (cinfo->progress != NULL) { + int nscans; + /* Estimate number of scans to set pass_limit. */ + if (cinfo->process == JPROC_PROGRESSIVE) { + /* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */ + nscans = 2 + 3 * cinfo->num_components; + } else if (cinfo->inputctl->has_multiple_scans) { + /* For a nonprogressive multiscan file, estimate 1 scan per component. */ + nscans = cinfo->num_components; + } else { + nscans = 1; + } + cinfo->progress->pass_counter = 0L; + cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans; + cinfo->progress->completed_passes = 0; + cinfo->progress->total_passes = 1; + } +} diff --git a/src/gdcmjpeg/jerror.c b/src/gdcmjpeg/jerror.c new file mode 100644 index 00000000..4e6e2e35 --- /dev/null +++ b/src/gdcmjpeg/jerror.c @@ -0,0 +1,252 @@ +/* + * jerror.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains simple error-reporting and trace-message routines. + * These are suitable for Unix-like systems and others where writing to + * stderr is the right thing to do. Many applications will want to replace + * some or all of these routines. + * + * If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile, + * you get a Windows-specific hack to display error messages in a dialog box. + * It ain't much, but it beats dropping error messages into the bit bucket, + * which is what happens to output to stderr under most Windows C compilers. + * + * These routines are used by both the compression and decompression code. + */ + +/* this is not a core library module, so it doesn't define JPEG_INTERNALS */ +#include "jinclude.h" +#include "jpeglib.h" +#include "jversion.h" +#include "jerror.h" + +#ifdef USE_WINDOWS_MESSAGEBOX +#include +#endif + +#ifndef EXIT_FAILURE /* define exit() codes if not provided */ +#define EXIT_FAILURE 1 +#endif + + +/* + * Create the message string table. + * We do this from the master message list in jerror.h by re-reading + * jerror.h with a suitable definition for macro JMESSAGE. + * The message table is made an external symbol just in case any applications + * want to refer to it directly. + */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jpeg_std_message_table jMsgTable +#endif + +#define JMESSAGE(code,string) string , + +const char * const jpeg_std_message_table[] = { +#include "jerror.h" + NULL +}; + + +/* + * Error exit handler: must not return to caller. + * + * Applications may override this if they want to get control back after + * an error. Typically one would longjmp somewhere instead of exiting. + * The setjmp buffer can be made a private field within an expanded error + * handler object. Note that the info needed to generate an error message + * is stored in the error object, so you can generate the message now or + * later, at your convenience. + * You should make sure that the JPEG object is cleaned up (with jpeg_abort + * or jpeg_destroy) at some point. + */ + +METHODDEF(void) +error_exit (j_common_ptr cinfo) +{ + /* Always display the message */ + (*cinfo->err->output_message) (cinfo); + + /* Let the memory manager delete any temp files before we die */ + jpeg_destroy(cinfo); + + exit(EXIT_FAILURE); +} + + +/* + * Actual output of an error or trace message. + * Applications may override this method to send JPEG messages somewhere + * other than stderr. + * + * On Windows, printing to stderr is generally completely useless, + * so we provide optional code to produce an error-dialog popup. + * Most Windows applications will still prefer to override this routine, + * but if they don't, it'll do something at least marginally useful. + * + * NOTE: to use the library in an environment that doesn't support the + * C stdio library, you may have to delete the call to fprintf() entirely, + * not just not use this routine. + */ + +METHODDEF(void) +output_message (j_common_ptr cinfo) +{ + char buffer[JMSG_LENGTH_MAX]; + + /* Create the message */ + (*cinfo->err->format_message) (cinfo, buffer); + +#ifdef USE_WINDOWS_MESSAGEBOX + /* Display it in a message dialog box */ + MessageBox(GetActiveWindow(), buffer, "JPEG Library Error", + MB_OK | MB_ICONERROR); +#else + /* Send it to stderr, adding a newline */ + fprintf(stderr, "%s\n", buffer); +#endif +} + + +/* + * Decide whether to emit a trace or warning message. + * msg_level is one of: + * -1: recoverable corrupt-data warning, may want to abort. + * 0: important advisory messages (always display to user). + * 1: first level of tracing detail. + * 2,3,...: successively more detailed tracing messages. + * An application might override this method if it wanted to abort on warnings + * or change the policy about which messages to display. + */ + +METHODDEF(void) +emit_message (j_common_ptr cinfo, int msg_level) +{ + struct jpeg_error_mgr * err = cinfo->err; + + if (msg_level < 0) { + /* It's a warning message. Since corrupt files may generate many warnings, + * the policy implemented here is to show only the first warning, + * unless trace_level >= 3. + */ + if (err->num_warnings == 0 || err->trace_level >= 3) + (*err->output_message) (cinfo); + /* Always count warnings in num_warnings. */ + err->num_warnings++; + } else { + /* It's a trace message. Show it if trace_level >= msg_level. */ + if (err->trace_level >= msg_level) + (*err->output_message) (cinfo); + } +} + + +/* + * Format a message string for the most recent JPEG error or message. + * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX + * characters. Note that no '\n' character is added to the string. + * Few applications should need to override this method. + */ + +METHODDEF(void) +format_message (j_common_ptr cinfo, char * buffer) +{ + struct jpeg_error_mgr * err = cinfo->err; + int msg_code = err->msg_code; + const char * msgtext = NULL; + const char * msgptr; + char ch; + boolean isstring; + + /* Look up message string in proper table */ + if (msg_code > 0 && msg_code <= err->last_jpeg_message) { + msgtext = err->jpeg_message_table[msg_code]; + } else if (err->addon_message_table != NULL && + msg_code >= err->first_addon_message && + msg_code <= err->last_addon_message) { + msgtext = err->addon_message_table[msg_code - err->first_addon_message]; + } + + /* Defend against bogus message number */ + if (msgtext == NULL) { + err->msg_parm.i[0] = msg_code; + msgtext = err->jpeg_message_table[0]; + } + + /* Check for string parameter, as indicated by %s in the message text */ + isstring = FALSE; + msgptr = msgtext; + while ((ch = *msgptr++) != '\0') { + if (ch == '%') { + if (*msgptr == 's') isstring = TRUE; + break; + } + } + + /* Format the message into the passed buffer */ + if (isstring) + sprintf(buffer, msgtext, err->msg_parm.s); + else + sprintf(buffer, msgtext, + err->msg_parm.i[0], err->msg_parm.i[1], + err->msg_parm.i[2], err->msg_parm.i[3], + err->msg_parm.i[4], err->msg_parm.i[5], + err->msg_parm.i[6], err->msg_parm.i[7]); +} + + +/* + * Reset error state variables at start of a new image. + * This is called during compression startup to reset trace/error + * processing to default state, without losing any application-specific + * method pointers. An application might possibly want to override + * this method if it has additional error processing state. + */ + +METHODDEF(void) +reset_error_mgr (j_common_ptr cinfo) +{ + cinfo->err->num_warnings = 0; + /* trace_level is not reset since it is an application-supplied parameter */ + cinfo->err->msg_code = 0; /* may be useful as a flag for "no error" */ +} + + +/* + * Fill in the standard error-handling methods in a jpeg_error_mgr object. + * Typical call is: + * struct jpeg_compress_struct cinfo; + * struct jpeg_error_mgr err; + * + * cinfo.err = jpeg_std_error(&err); + * after which the application may override some of the methods. + */ + +GLOBAL(struct jpeg_error_mgr *) +jpeg_std_error (struct jpeg_error_mgr * err) +{ + err->error_exit = error_exit; + err->emit_message = emit_message; + err->output_message = output_message; + err->format_message = format_message; + err->reset_error_mgr = reset_error_mgr; + + err->trace_level = 0; /* default = no tracing */ + err->num_warnings = 0; /* no warnings emitted yet */ + err->msg_code = 0; /* may be useful as a flag for "no error" */ + + /* Initialize message table pointers */ + err->jpeg_message_table = jpeg_std_message_table; + err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1; + + err->addon_message_table = NULL; + err->first_addon_message = 0; /* for safety */ + err->last_addon_message = 0; + + return err; +} diff --git a/src/gdcmjpeg/jerror.h b/src/gdcmjpeg/jerror.h new file mode 100644 index 00000000..d48ccfad --- /dev/null +++ b/src/gdcmjpeg/jerror.h @@ -0,0 +1,306 @@ +/* + * jerror.h + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file defines the error and message codes for the JPEG library. + * Edit this file to add new codes, or to translate the message strings to + * some other language. + * A set of error-reporting macros are defined too. Some applications using + * the JPEG library may wish to include this file to get the error codes + * and/or the macros. + */ + +/* + * To define the enum list of message codes, include this file without + * defining macro JMESSAGE. To create a message string table, include it + * again with a suitable JMESSAGE definition (see jerror.c for an example). + */ +#ifndef JMESSAGE +#ifndef JERROR_H +/* First time through, define the enum list */ +#define JMAKE_ENUM_LIST +#else +/* Repeated inclusions of this file are no-ops unless JMESSAGE is defined */ +#define JMESSAGE(code,string) +#endif /* JERROR_H */ +#endif /* JMESSAGE */ + +#ifdef JMAKE_ENUM_LIST + +typedef enum { + +#define JMESSAGE(code,string) code , + +#endif /* JMAKE_ENUM_LIST */ + +JMESSAGE(JMSG_NOMESSAGE, "Bogus message code %d") /* Must be first entry! */ + +/* For maintenance convenience, list is alphabetical by message code name */ +JMESSAGE(JERR_ARITH_NOTIMPL, + "Sorry, there are legal restrictions on arithmetic coding") +JMESSAGE(JERR_BAD_ALIGN_TYPE, "ALIGN_TYPE is wrong, please fix") +JMESSAGE(JERR_BAD_ALLOC_CHUNK, "MAX_ALLOC_CHUNK is wrong, please fix") +JMESSAGE(JERR_BAD_BUFFER_MODE, "Bogus buffer control mode") +JMESSAGE(JERR_BAD_COMPONENT_ID, "Invalid component ID %d in SOS") +JMESSAGE(JERR_BAD_DCT_COEF, "DCT coefficient out of range") +JMESSAGE(JERR_BAD_DCTSIZE, "IDCT output block size %d not supported") +JMESSAGE(JERR_BAD_DIFF, "spatial difference out of range") +JMESSAGE(JERR_BAD_HUFF_TABLE, "Bogus Huffman table definition") +JMESSAGE(JERR_BAD_IN_COLORSPACE, "Bogus input colorspace") +JMESSAGE(JERR_BAD_J_COLORSPACE, "Bogus JPEG colorspace") +JMESSAGE(JERR_BAD_LENGTH, "Bogus marker length") +JMESSAGE(JERR_BAD_LIB_VERSION, + "Wrong JPEG library version: library is %d, caller expects %d") +JMESSAGE(JERR_BAD_LOSSLESS, + "Invalid lossless parameters Ss=%d Se=%d Ah=%d Al=%d") +JMESSAGE(JERR_BAD_LOSSLESS_SCRIPT, + "Invalid lossless parameters at scan script entry %d") +JMESSAGE(JERR_BAD_MCU_SIZE, "Sampling factors too large for interleaved scan") +JMESSAGE(JERR_BAD_POOL_ID, "Invalid memory pool code %d") +JMESSAGE(JERR_BAD_PRECISION, "Unsupported JPEG data precision %d") +JMESSAGE(JERR_BAD_PROGRESSION, + "Invalid progressive parameters Ss=%d Se=%d Ah=%d Al=%d") +JMESSAGE(JERR_BAD_PROG_SCRIPT, + "Invalid progressive parameters at scan script entry %d") +JMESSAGE(JERR_BAD_RESTART, "Invalid restart interval: %d, must be an integer multiple of the number of MCUs in an MCU_row (%d)") +JMESSAGE(JERR_BAD_SAMPLING, "Bogus sampling factors") +JMESSAGE(JERR_BAD_SCAN_SCRIPT, "Invalid scan script at entry %d") +JMESSAGE(JERR_BAD_STATE, "Improper call to JPEG library in state %d") +JMESSAGE(JERR_BAD_STRUCT_SIZE, + "JPEG parameter struct mismatch: library thinks size is %u, caller expects %u") +JMESSAGE(JERR_BAD_VIRTUAL_ACCESS, "Bogus virtual array access") +JMESSAGE(JERR_BUFFER_SIZE, "Buffer passed to JPEG library is too small") +JMESSAGE(JERR_CANT_SUSPEND, "Suspension not allowed here") +JMESSAGE(JERR_CANT_TRANSCODE, + "Cannot transcode to/from lossless JPEG datastreams") +JMESSAGE(JERR_CCIR601_NOTIMPL, "CCIR601 sampling not implemented yet") +JMESSAGE(JERR_COMPONENT_COUNT, "Too many color components: %d, max %d") +JMESSAGE(JERR_CONVERSION_NOTIMPL, "Unsupported color conversion request") +JMESSAGE(JERR_DAC_INDEX, "Bogus DAC index %d") +JMESSAGE(JERR_DAC_VALUE, "Bogus DAC value 0x%x") +JMESSAGE(JERR_DHT_INDEX, "Bogus DHT index %d") +JMESSAGE(JERR_DQT_INDEX, "Bogus DQT index %d") +JMESSAGE(JERR_EMPTY_IMAGE, "Empty JPEG image (DNL not supported)") +JMESSAGE(JERR_EMS_READ, "Read from EMS failed") +JMESSAGE(JERR_EMS_WRITE, "Write to EMS failed") +JMESSAGE(JERR_EOI_EXPECTED, "Didn't expect more than one scan") +JMESSAGE(JERR_FILE_READ, "Input file read error") +JMESSAGE(JERR_FILE_WRITE, "Output file write error --- out of disk space?") +JMESSAGE(JERR_FRACT_SAMPLE_NOTIMPL, "Fractional sampling not implemented yet") +JMESSAGE(JERR_HUFF_CLEN_OVERFLOW, "Huffman code size table overflow") +JMESSAGE(JERR_HUFF_MISSING_CODE, "Missing Huffman code table entry") +JMESSAGE(JERR_IMAGE_TOO_BIG, "Maximum supported image dimension is %u pixels") +JMESSAGE(JERR_INPUT_EMPTY, "Empty input file") +JMESSAGE(JERR_INPUT_EOF, "Premature end of input file") +JMESSAGE(JERR_MISMATCHED_QUANT_TABLE, + "Cannot transcode due to multiple use of quantization table %d") +JMESSAGE(JERR_MISSING_DATA, "Scan script does not transmit all data") +JMESSAGE(JERR_MODE_CHANGE, "Invalid color quantization mode change") +JMESSAGE(JERR_NOTIMPL, "Not implemented yet") +JMESSAGE(JERR_NOT_COMPILED, "Requested feature was omitted at compile time") +JMESSAGE(JERR_NO_ARITH_TABLE, "Arithmetic table 0x%02x was not defined") +JMESSAGE(JERR_NO_BACKING_STORE, "Backing store not supported") +JMESSAGE(JERR_NO_HUFF_TABLE, "Huffman table 0x%02x was not defined") +JMESSAGE(JERR_NO_IMAGE, "JPEG datastream contains no image") +JMESSAGE(JERR_NO_LOSSLESS_SCRIPT, "Lossless encoding was requested but no scan script was supplied") +JMESSAGE(JERR_NO_QUANT_TABLE, "Quantization table 0x%02x was not defined") +JMESSAGE(JERR_NO_SOI, "Not a JPEG file: starts with 0x%02x 0x%02x") +JMESSAGE(JERR_OUT_OF_MEMORY, "Insufficient memory (case %d)") +JMESSAGE(JERR_QUANT_COMPONENTS, + "Cannot quantize more than %d color components") +JMESSAGE(JERR_QUANT_FEW_COLORS, "Cannot quantize to fewer than %d colors") +JMESSAGE(JERR_QUANT_MANY_COLORS, "Cannot quantize to more than %d colors") +JMESSAGE(JERR_SOF_DUPLICATE, "Invalid JPEG file structure: two SOF markers") +JMESSAGE(JERR_SOF_NO_SOS, "Invalid JPEG file structure: missing SOS marker") +JMESSAGE(JERR_SOF_UNSUPPORTED, "Unsupported JPEG process: SOF type 0x%02x") +JMESSAGE(JERR_SOI_DUPLICATE, "Invalid JPEG file structure: two SOI markers") +JMESSAGE(JERR_SOS_NO_SOF, "Invalid JPEG file structure: SOS before SOF") +JMESSAGE(JERR_TFILE_CREATE, "Failed to create temporary file %s") +JMESSAGE(JERR_TFILE_READ, "Read failed on temporary file") +JMESSAGE(JERR_TFILE_SEEK, "Seek failed on temporary file") +JMESSAGE(JERR_TFILE_WRITE, + "Write failed on temporary file --- out of disk space?") +JMESSAGE(JERR_TOO_LITTLE_DATA, "Application transferred too few scanlines") +JMESSAGE(JERR_UNKNOWN_MARKER, "Unsupported marker type 0x%02x") +JMESSAGE(JERR_VIRTUAL_BUG, "Virtual array controller messed up") +JMESSAGE(JERR_WIDTH_OVERFLOW, "Image too wide for this implementation") +JMESSAGE(JERR_XMS_READ, "Read from XMS failed") +JMESSAGE(JERR_XMS_WRITE, "Write to XMS failed") +JMESSAGE(JMSG_COPYRIGHT, JCOPYRIGHT) +JMESSAGE(JMSG_VERSION, JVERSION) +JMESSAGE(JTRC_16BIT_TABLES, + "Caution: quantization tables are too coarse for baseline JPEG") +JMESSAGE(JTRC_ADOBE, + "Adobe APP14 marker: version %d, flags 0x%04x 0x%04x, transform %d") +JMESSAGE(JTRC_APP0, "Unknown APP0 marker (not JFIF), length %u") +JMESSAGE(JTRC_APP14, "Unknown APP14 marker (not Adobe), length %u") +JMESSAGE(JTRC_DAC, "Define Arithmetic Table 0x%02x: 0x%02x") +JMESSAGE(JTRC_DHT, "Define Huffman Table 0x%02x") +JMESSAGE(JTRC_DQT, "Define Quantization Table %d precision %d") +JMESSAGE(JTRC_DRI, "Define Restart Interval %u") +JMESSAGE(JTRC_EMS_CLOSE, "Freed EMS handle %u") +JMESSAGE(JTRC_EMS_OPEN, "Obtained EMS handle %u") +JMESSAGE(JTRC_EOI, "End Of Image") +JMESSAGE(JTRC_HUFFBITS, " %3d %3d %3d %3d %3d %3d %3d %3d") +JMESSAGE(JTRC_JFIF, "JFIF APP0 marker: version %d.%02d, density %dx%d %d") +JMESSAGE(JTRC_JFIF_BADTHUMBNAILSIZE, + "Warning: thumbnail image size does not match data length %u") +JMESSAGE(JTRC_JFIF_EXTENSION, + "JFIF extension marker: type 0x%02x, length %u") +JMESSAGE(JTRC_JFIF_THUMBNAIL, " with %d x %d thumbnail image") +JMESSAGE(JTRC_MISC_MARKER, "Miscellaneous marker 0x%02x, length %u") +JMESSAGE(JTRC_PARMLESS_MARKER, "Unexpected marker 0x%02x") +JMESSAGE(JTRC_QUANTVALS, " %4u %4u %4u %4u %4u %4u %4u %4u") +JMESSAGE(JTRC_QUANT_3_NCOLORS, "Quantizing to %d = %d*%d*%d colors") +JMESSAGE(JTRC_QUANT_NCOLORS, "Quantizing to %d colors") +JMESSAGE(JTRC_QUANT_SELECTED, "Selected %d colors for quantization") +JMESSAGE(JTRC_RECOVERY_ACTION, "At marker 0x%02x, recovery action %d") +JMESSAGE(JTRC_RST, "RST%d") +JMESSAGE(JTRC_SMOOTH_NOTIMPL, + "Smoothing not supported with nonstandard sampling ratios") +JMESSAGE(JTRC_SOF, "Start Of Frame 0x%02x: width=%u, height=%u, components=%d") +JMESSAGE(JTRC_SOF_COMPONENT, " Component %d: %dhx%dv q=%d") +JMESSAGE(JTRC_SOI, "Start of Image") +JMESSAGE(JTRC_SOS, "Start Of Scan: %d components") +JMESSAGE(JTRC_SOS_COMPONENT, " Component %d: dc=%d ac=%d") +JMESSAGE(JTRC_SOS_PARAMS, " Ss=%d, Se=%d, Ah=%d, Al=%d") +JMESSAGE(JTRC_TFILE_CLOSE, "Closed temporary file %s") +JMESSAGE(JTRC_TFILE_OPEN, "Opened temporary file %s") +JMESSAGE(JTRC_THUMB_JPEG, + "JFIF extension marker: JPEG-compressed thumbnail image, length %u") +JMESSAGE(JTRC_THUMB_PALETTE, + "JFIF extension marker: palette thumbnail image, length %u") +JMESSAGE(JTRC_THUMB_RGB, + "JFIF extension marker: RGB thumbnail image, length %u") +JMESSAGE(JTRC_UNKNOWN_LOSSLESS_IDS, + "Unrecognized component IDs %d %d %d, assuming RGB") +JMESSAGE(JTRC_UNKNOWN_LOSSY_IDS, + "Unrecognized component IDs %d %d %d, assuming YCbCr") +JMESSAGE(JTRC_XMS_CLOSE, "Freed XMS handle %u") +JMESSAGE(JTRC_XMS_OPEN, "Obtained XMS handle %u") +JMESSAGE(JWRN_ADOBE_XFORM, "Unknown Adobe color transform code %d") +JMESSAGE(JWRN_ARITH_BAD_CODE, "Corrupt JPEG data: bad arithmetic code") +JMESSAGE(JWRN_BOGUS_PROGRESSION, + "Inconsistent progression sequence for component %d coefficient %d") +JMESSAGE(JWRN_EXTRANEOUS_DATA, + "Corrupt JPEG data: %u extraneous bytes before marker 0x%02x") +JMESSAGE(JWRN_HIT_MARKER, "Corrupt JPEG data: premature end of data segment") +JMESSAGE(JWRN_HUFF_BAD_CODE, "Corrupt JPEG data: bad Huffman code") +JMESSAGE(JWRN_JFIF_MAJOR, "Warning: unknown JFIF revision number %d.%02d") +JMESSAGE(JWRN_JPEG_EOF, "Premature end of JPEG file") +JMESSAGE(JWRN_MUST_DOWNSCALE, + "Must downscale data from %d bits to %d") +JMESSAGE(JWRN_MUST_RESYNC, + "Corrupt JPEG data: found marker 0x%02x instead of RST%d") +JMESSAGE(JWRN_NOT_SEQUENTIAL, "Invalid SOS parameters for sequential JPEG") +JMESSAGE(JWRN_TOO_MUCH_DATA, "Application transferred too many scanlines") + +#ifdef JMAKE_ENUM_LIST + + JMSG_LASTMSGCODE +} J_MESSAGE_CODE; + +#undef JMAKE_ENUM_LIST +#endif /* JMAKE_ENUM_LIST */ + +/* Zap JMESSAGE macro so that future re-inclusions do nothing by default */ +#undef JMESSAGE + + +#ifndef JERROR_H +#define JERROR_H + +/* Macros to simplify using the error and trace message stuff */ +/* The first parameter is either type of cinfo pointer */ + +/* Fatal errors (print message and exit) */ +#define ERREXIT(cinfo,code) \ + ((cinfo)->err->msg_code = (code), \ + (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo))) +#define ERREXIT1(cinfo,code,p1) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo))) +#define ERREXIT2(cinfo,code,p1,p2) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (cinfo)->err->msg_parm.i[1] = (p2), \ + (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo))) +#define ERREXIT3(cinfo,code,p1,p2,p3) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (cinfo)->err->msg_parm.i[1] = (p2), \ + (cinfo)->err->msg_parm.i[2] = (p3), \ + (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo))) +#define ERREXIT4(cinfo,code,p1,p2,p3,p4) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (cinfo)->err->msg_parm.i[1] = (p2), \ + (cinfo)->err->msg_parm.i[2] = (p3), \ + (cinfo)->err->msg_parm.i[3] = (p4), \ + (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo))) +#define ERREXITS(cinfo,code,str) \ + ((cinfo)->err->msg_code = (code), \ + strncpy((cinfo)->err->msg_parm.s, (str), JMSG_STR_PARM_MAX), \ + (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo))) + +#define MAKESTMT(stuff) do { stuff } while (0) + +/* Nonfatal errors (we can keep going, but the data is probably corrupt) */ +#define WARNMS(cinfo,code) \ + ((cinfo)->err->msg_code = (code), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), -1)) +#define WARNMS1(cinfo,code,p1) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), -1)) +#define WARNMS2(cinfo,code,p1,p2) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (cinfo)->err->msg_parm.i[1] = (p2), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), -1)) + +/* Informational/debugging messages */ +#define TRACEMS(cinfo,lvl,code) \ + ((cinfo)->err->msg_code = (code), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl))) +#define TRACEMS1(cinfo,lvl,code,p1) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl))) +#define TRACEMS2(cinfo,lvl,code,p1,p2) \ + ((cinfo)->err->msg_code = (code), \ + (cinfo)->err->msg_parm.i[0] = (p1), \ + (cinfo)->err->msg_parm.i[1] = (p2), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl))) +#define TRACEMS3(cinfo,lvl,code,p1,p2,p3) \ + MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \ + _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); \ + (cinfo)->err->msg_code = (code); \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); ) +#define TRACEMS4(cinfo,lvl,code,p1,p2,p3,p4) \ + MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \ + _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); _mp[3] = (p4); \ + (cinfo)->err->msg_code = (code); \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); ) +#define TRACEMS5(cinfo,lvl,code,p1,p2,p3,p4,p5) \ + MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \ + _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); _mp[3] = (p4); \ + _mp[4] = (p5); \ + (cinfo)->err->msg_code = (code); \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); ) +#define TRACEMS8(cinfo,lvl,code,p1,p2,p3,p4,p5,p6,p7,p8) \ + MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \ + _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); _mp[3] = (p4); \ + _mp[4] = (p5); _mp[5] = (p6); _mp[6] = (p7); _mp[7] = (p8); \ + (cinfo)->err->msg_code = (code); \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); ) +#define TRACEMSS(cinfo,lvl,code,str) \ + ((cinfo)->err->msg_code = (code), \ + strncpy((cinfo)->err->msg_parm.s, (str), JMSG_STR_PARM_MAX), \ + (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl))) + +#endif /* JERROR_H */ diff --git a/src/gdcmjpeg/jfdctflt.c b/src/gdcmjpeg/jfdctflt.c new file mode 100644 index 00000000..f0297a25 --- /dev/null +++ b/src/gdcmjpeg/jfdctflt.c @@ -0,0 +1,168 @@ +/* + * jfdctflt.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains a floating-point implementation of the + * forward DCT (Discrete Cosine Transform). + * + * This implementation should be more accurate than either of the integer + * DCT implementations. However, it may not give the same results on all + * machines because of differences in roundoff behavior. Speed will depend + * on the hardware's floating point capacity. + * + * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT + * on each column. Direct algorithms are also available, but they are + * much more complex and seem not to be any faster when reduced to code. + * + * This implementation is based on Arai, Agui, and Nakajima's algorithm for + * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in + * Japanese, but the algorithm is described in the Pennebaker & Mitchell + * JPEG textbook (see REFERENCES section in file README). The following code + * is based directly on figure 4-8 in P&M. + * While an 8-point DCT cannot be done in less than 11 multiplies, it is + * possible to arrange the computation so that many of the multiplies are + * simple scalings of the final outputs. These multiplies can then be + * folded into the multiplications or divisions by the JPEG quantization + * table entries. The AA&N method leaves only 5 multiplies and 29 adds + * to be done in the DCT itself. + * The primary disadvantage of this method is that with a fixed-point + * implementation, accuracy is lost due to imprecise representation of the + * scaled quantization values. However, that problem does not arise if + * we use floating point arithmetic. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef DCT_FLOAT_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* + * Perform the forward DCT on one block of samples. + */ + +GLOBAL(void) +jpeg_fdct_float (FAST_FLOAT * data) +{ + FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; + FAST_FLOAT tmp10, tmp11, tmp12, tmp13; + FAST_FLOAT z1, z2, z3, z4, z5, z11, z13; + FAST_FLOAT *dataptr; + int ctr; + + /* Pass 1: process rows. */ + + dataptr = data; + for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { + tmp0 = dataptr[0] + dataptr[7]; + tmp7 = dataptr[0] - dataptr[7]; + tmp1 = dataptr[1] + dataptr[6]; + tmp6 = dataptr[1] - dataptr[6]; + tmp2 = dataptr[2] + dataptr[5]; + tmp5 = dataptr[2] - dataptr[5]; + tmp3 = dataptr[3] + dataptr[4]; + tmp4 = dataptr[3] - dataptr[4]; + + /* Even part */ + + tmp10 = tmp0 + tmp3; /* phase 2 */ + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + dataptr[0] = tmp10 + tmp11; /* phase 3 */ + dataptr[4] = tmp10 - tmp11; + + z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */ + dataptr[2] = tmp13 + z1; /* phase 5 */ + dataptr[6] = tmp13 - z1; + + /* Odd part */ + + tmp10 = tmp4 + tmp5; /* phase 2 */ + tmp11 = tmp5 + tmp6; + tmp12 = tmp6 + tmp7; + + /* The rotator is modified from fig 4-8 to avoid extra negations. */ + z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */ + z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */ + z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */ + z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */ + + z11 = tmp7 + z3; /* phase 5 */ + z13 = tmp7 - z3; + + dataptr[5] = z13 + z2; /* phase 6 */ + dataptr[3] = z13 - z2; + dataptr[1] = z11 + z4; + dataptr[7] = z11 - z4; + + dataptr += DCTSIZE; /* advance pointer to next row */ + } + + /* Pass 2: process columns. */ + + dataptr = data; + for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { + tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7]; + tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7]; + tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6]; + tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6]; + tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5]; + tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5]; + tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4]; + tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4]; + + /* Even part */ + + tmp10 = tmp0 + tmp3; /* phase 2 */ + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */ + dataptr[DCTSIZE*4] = tmp10 - tmp11; + + z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */ + dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */ + dataptr[DCTSIZE*6] = tmp13 - z1; + + /* Odd part */ + + tmp10 = tmp4 + tmp5; /* phase 2 */ + tmp11 = tmp5 + tmp6; + tmp12 = tmp6 + tmp7; + + /* The rotator is modified from fig 4-8 to avoid extra negations. */ + z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */ + z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */ + z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */ + z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */ + + z11 = tmp7 + z3; /* phase 5 */ + z13 = tmp7 - z3; + + dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */ + dataptr[DCTSIZE*3] = z13 - z2; + dataptr[DCTSIZE*1] = z11 + z4; + dataptr[DCTSIZE*7] = z11 - z4; + + dataptr++; /* advance pointer to next column */ + } +} + +#endif /* DCT_FLOAT_SUPPORTED */ diff --git a/src/gdcmjpeg/jfdctfst.c b/src/gdcmjpeg/jfdctfst.c new file mode 100644 index 00000000..5d51e3c1 --- /dev/null +++ b/src/gdcmjpeg/jfdctfst.c @@ -0,0 +1,224 @@ +/* + * jfdctfst.c + * + * Copyright (C) 1994-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains a fast, not so accurate integer implementation of the + * forward DCT (Discrete Cosine Transform). + * + * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT + * on each column. Direct algorithms are also available, but they are + * much more complex and seem not to be any faster when reduced to code. + * + * This implementation is based on Arai, Agui, and Nakajima's algorithm for + * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in + * Japanese, but the algorithm is described in the Pennebaker & Mitchell + * JPEG textbook (see REFERENCES section in file README). The following code + * is based directly on figure 4-8 in P&M. + * While an 8-point DCT cannot be done in less than 11 multiplies, it is + * possible to arrange the computation so that many of the multiplies are + * simple scalings of the final outputs. These multiplies can then be + * folded into the multiplications or divisions by the JPEG quantization + * table entries. The AA&N method leaves only 5 multiplies and 29 adds + * to be done in the DCT itself. + * The primary disadvantage of this method is that with fixed-point math, + * accuracy is lost due to imprecise representation of the scaled + * quantization values. The smaller the quantization table entry, the less + * precise the scaled value, so this implementation does worse with high- + * quality-setting files than with low-quality ones. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef DCT_IFAST_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* Scaling decisions are generally the same as in the LL&M algorithm; + * see jfdctint.c for more details. However, we choose to descale + * (right shift) multiplication products as soon as they are formed, + * rather than carrying additional fractional bits into subsequent additions. + * This compromises accuracy slightly, but it lets us save a few shifts. + * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples) + * everywhere except in the multiplications proper; this saves a good deal + * of work on 16-bit-int machines. + * + * Again to save a few shifts, the intermediate results between pass 1 and + * pass 2 are not upscaled, but are represented only to integral precision. + * + * A final compromise is to represent the multiplicative constants to only + * 8 fractional bits, rather than 13. This saves some shifting work on some + * machines, and may also reduce the cost of multiplication (since there + * are fewer one-bits in the constants). + */ + +#define CONST_BITS 8 + + +/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus + * causing a lot of useless floating-point operations at run time. + * To get around this we use the following pre-calculated constants. + * If you change CONST_BITS you may want to add appropriate values. + * (With a reasonable C compiler, you can just rely on the FIX() macro...) + */ + +#if CONST_BITS == 8 +#define FIX_0_382683433 ((INT32) 98) /* FIX(0.382683433) */ +#define FIX_0_541196100 ((INT32) 139) /* FIX(0.541196100) */ +#define FIX_0_707106781 ((INT32) 181) /* FIX(0.707106781) */ +#define FIX_1_306562965 ((INT32) 334) /* FIX(1.306562965) */ +#else +#define FIX_0_382683433 FIX(0.382683433) +#define FIX_0_541196100 FIX(0.541196100) +#define FIX_0_707106781 FIX(0.707106781) +#define FIX_1_306562965 FIX(1.306562965) +#endif + + +/* We can gain a little more speed, with a further compromise in accuracy, + * by omitting the addition in a descaling shift. This yields an incorrectly + * rounded result half the time... + */ + +#ifndef USE_ACCURATE_ROUNDING +#undef DESCALE +#define DESCALE(x,n) RIGHT_SHIFT(x, n) +#endif + + +/* Multiply a DCTELEM variable by an INT32 constant, and immediately + * descale to yield a DCTELEM result. + */ + +#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS)) + + +/* + * Perform the forward DCT on one block of samples. + */ + +GLOBAL(void) +jpeg_fdct_ifast (DCTELEM * data) +{ + DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; + DCTELEM tmp10, tmp11, tmp12, tmp13; + DCTELEM z1, z2, z3, z4, z5, z11, z13; + DCTELEM *dataptr; + int ctr; + SHIFT_TEMPS + + /* Pass 1: process rows. */ + + dataptr = data; + for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { + tmp0 = dataptr[0] + dataptr[7]; + tmp7 = dataptr[0] - dataptr[7]; + tmp1 = dataptr[1] + dataptr[6]; + tmp6 = dataptr[1] - dataptr[6]; + tmp2 = dataptr[2] + dataptr[5]; + tmp5 = dataptr[2] - dataptr[5]; + tmp3 = dataptr[3] + dataptr[4]; + tmp4 = dataptr[3] - dataptr[4]; + + /* Even part */ + + tmp10 = tmp0 + tmp3; /* phase 2 */ + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + dataptr[0] = tmp10 + tmp11; /* phase 3 */ + dataptr[4] = tmp10 - tmp11; + + z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */ + dataptr[2] = tmp13 + z1; /* phase 5 */ + dataptr[6] = tmp13 - z1; + + /* Odd part */ + + tmp10 = tmp4 + tmp5; /* phase 2 */ + tmp11 = tmp5 + tmp6; + tmp12 = tmp6 + tmp7; + + /* The rotator is modified from fig 4-8 to avoid extra negations. */ + z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */ + z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */ + z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */ + z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */ + + z11 = tmp7 + z3; /* phase 5 */ + z13 = tmp7 - z3; + + dataptr[5] = z13 + z2; /* phase 6 */ + dataptr[3] = z13 - z2; + dataptr[1] = z11 + z4; + dataptr[7] = z11 - z4; + + dataptr += DCTSIZE; /* advance pointer to next row */ + } + + /* Pass 2: process columns. */ + + dataptr = data; + for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { + tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7]; + tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7]; + tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6]; + tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6]; + tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5]; + tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5]; + tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4]; + tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4]; + + /* Even part */ + + tmp10 = tmp0 + tmp3; /* phase 2 */ + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */ + dataptr[DCTSIZE*4] = tmp10 - tmp11; + + z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */ + dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */ + dataptr[DCTSIZE*6] = tmp13 - z1; + + /* Odd part */ + + tmp10 = tmp4 + tmp5; /* phase 2 */ + tmp11 = tmp5 + tmp6; + tmp12 = tmp6 + tmp7; + + /* The rotator is modified from fig 4-8 to avoid extra negations. */ + z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */ + z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */ + z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */ + z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */ + + z11 = tmp7 + z3; /* phase 5 */ + z13 = tmp7 - z3; + + dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */ + dataptr[DCTSIZE*3] = z13 - z2; + dataptr[DCTSIZE*1] = z11 + z4; + dataptr[DCTSIZE*7] = z11 - z4; + + dataptr++; /* advance pointer to next column */ + } +} + +#endif /* DCT_IFAST_SUPPORTED */ diff --git a/src/gdcmjpeg/jfdctint.c b/src/gdcmjpeg/jfdctint.c new file mode 100644 index 00000000..8f6c73db --- /dev/null +++ b/src/gdcmjpeg/jfdctint.c @@ -0,0 +1,283 @@ +/* + * jfdctint.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains a slow-but-accurate integer implementation of the + * forward DCT (Discrete Cosine Transform). + * + * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT + * on each column. Direct algorithms are also available, but they are + * much more complex and seem not to be any faster when reduced to code. + * + * This implementation is based on an algorithm described in + * C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT + * Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics, + * Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991. + * The primary algorithm described there uses 11 multiplies and 29 adds. + * We use their alternate method with 12 multiplies and 32 adds. + * The advantage of this method is that no data path contains more than one + * multiplication; this allows a very simple and accurate implementation in + * scaled fixed-point arithmetic, with a minimal number of shifts. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef DCT_ISLOW_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* + * The poop on this scaling stuff is as follows: + * + * Each 1-D DCT step produces outputs which are a factor of sqrt(N) + * larger than the true DCT outputs. The final outputs are therefore + * a factor of N larger than desired; since N=8 this can be cured by + * a simple right shift at the end of the algorithm. The advantage of + * this arrangement is that we save two multiplications per 1-D DCT, + * because the y0 and y4 outputs need not be divided by sqrt(N). + * In the IJG code, this factor of 8 is removed by the quantization step + * (in jcdctmgr.c), NOT in this module. + * + * We have to do addition and subtraction of the integer inputs, which + * is no problem, and multiplication by fractional constants, which is + * a problem to do in integer arithmetic. We multiply all the constants + * by CONST_SCALE and convert them to integer constants (thus retaining + * CONST_BITS bits of precision in the constants). After doing a + * multiplication we have to divide the product by CONST_SCALE, with proper + * rounding, to produce the correct output. This division can be done + * cheaply as a right shift of CONST_BITS bits. We postpone shifting + * as long as possible so that partial sums can be added together with + * full fractional precision. + * + * The outputs of the first pass are scaled up by PASS1_BITS bits so that + * they are represented to better-than-integral precision. These outputs + * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word + * with the recommended scaling. (For 12-bit sample data, the intermediate + * array is INT32 anyway.) + * + * To avoid overflow of the 32-bit intermediate results in pass 2, we must + * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26. Error analysis + * shows that the values given below are the most effective. + */ + +#if BITS_IN_JSAMPLE == 8 +#define CONST_BITS 13 +#define PASS1_BITS 2 +#else +#define CONST_BITS 13 +#define PASS1_BITS 1 /* lose a little precision to avoid overflow */ +#endif + +/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus + * causing a lot of useless floating-point operations at run time. + * To get around this we use the following pre-calculated constants. + * If you change CONST_BITS you may want to add appropriate values. + * (With a reasonable C compiler, you can just rely on the FIX() macro...) + */ + +#if CONST_BITS == 13 +#define FIX_0_298631336 ((INT32) 2446) /* FIX(0.298631336) */ +#define FIX_0_390180644 ((INT32) 3196) /* FIX(0.390180644) */ +#define FIX_0_541196100 ((INT32) 4433) /* FIX(0.541196100) */ +#define FIX_0_765366865 ((INT32) 6270) /* FIX(0.765366865) */ +#define FIX_0_899976223 ((INT32) 7373) /* FIX(0.899976223) */ +#define FIX_1_175875602 ((INT32) 9633) /* FIX(1.175875602) */ +#define FIX_1_501321110 ((INT32) 12299) /* FIX(1.501321110) */ +#define FIX_1_847759065 ((INT32) 15137) /* FIX(1.847759065) */ +#define FIX_1_961570560 ((INT32) 16069) /* FIX(1.961570560) */ +#define FIX_2_053119869 ((INT32) 16819) /* FIX(2.053119869) */ +#define FIX_2_562915447 ((INT32) 20995) /* FIX(2.562915447) */ +#define FIX_3_072711026 ((INT32) 25172) /* FIX(3.072711026) */ +#else +#define FIX_0_298631336 FIX(0.298631336) +#define FIX_0_390180644 FIX(0.390180644) +#define FIX_0_541196100 FIX(0.541196100) +#define FIX_0_765366865 FIX(0.765366865) +#define FIX_0_899976223 FIX(0.899976223) +#define FIX_1_175875602 FIX(1.175875602) +#define FIX_1_501321110 FIX(1.501321110) +#define FIX_1_847759065 FIX(1.847759065) +#define FIX_1_961570560 FIX(1.961570560) +#define FIX_2_053119869 FIX(2.053119869) +#define FIX_2_562915447 FIX(2.562915447) +#define FIX_3_072711026 FIX(3.072711026) +#endif + + +/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result. + * For 8-bit samples with the recommended scaling, all the variable + * and constant values involved are no more than 16 bits wide, so a + * 16x16->32 bit multiply can be used instead of a full 32x32 multiply. + * For 12-bit samples, a full 32-bit multiplication will be needed. + */ + +#if BITS_IN_JSAMPLE == 8 +#define MULTIPLY(var,const) MULTIPLY16C16(var,const) +#else +#define MULTIPLY(var,const) ((var) * (const)) +#endif + + +/* + * Perform the forward DCT on one block of samples. + */ + +GLOBAL(void) +jpeg_fdct_islow (DCTELEM * data) +{ + INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; + INT32 tmp10, tmp11, tmp12, tmp13; + INT32 z1, z2, z3, z4, z5; + DCTELEM *dataptr; + int ctr; + SHIFT_TEMPS + + /* Pass 1: process rows. */ + /* Note results are scaled up by sqrt(8) compared to a true DCT; */ + /* furthermore, we scale the results by 2**PASS1_BITS. */ + + dataptr = data; + for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { + tmp0 = dataptr[0] + dataptr[7]; + tmp7 = dataptr[0] - dataptr[7]; + tmp1 = dataptr[1] + dataptr[6]; + tmp6 = dataptr[1] - dataptr[6]; + tmp2 = dataptr[2] + dataptr[5]; + tmp5 = dataptr[2] - dataptr[5]; + tmp3 = dataptr[3] + dataptr[4]; + tmp4 = dataptr[3] - dataptr[4]; + + /* Even part per LL&M figure 1 --- note that published figure is faulty; + * rotator "sqrt(2)*c1" should be "sqrt(2)*c6". + */ + + tmp10 = tmp0 + tmp3; + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + dataptr[0] = (DCTELEM) ((tmp10 + tmp11) << PASS1_BITS); + dataptr[4] = (DCTELEM) ((tmp10 - tmp11) << PASS1_BITS); + + z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100); + dataptr[2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865), + CONST_BITS-PASS1_BITS); + dataptr[6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065), + CONST_BITS-PASS1_BITS); + + /* Odd part per figure 8 --- note paper omits factor of sqrt(2). + * cK represents cos(K*pi/16). + * i0..i3 in the paper are tmp4..tmp7 here. + */ + + z1 = tmp4 + tmp7; + z2 = tmp5 + tmp6; + z3 = tmp4 + tmp6; + z4 = tmp5 + tmp7; + z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */ + + tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */ + tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */ + tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */ + tmp7 = MULTIPLY(tmp7, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */ + z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */ + z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */ + z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */ + z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */ + + z3 += z5; + z4 += z5; + + dataptr[7] = (DCTELEM) DESCALE(tmp4 + z1 + z3, CONST_BITS-PASS1_BITS); + dataptr[5] = (DCTELEM) DESCALE(tmp5 + z2 + z4, CONST_BITS-PASS1_BITS); + dataptr[3] = (DCTELEM) DESCALE(tmp6 + z2 + z3, CONST_BITS-PASS1_BITS); + dataptr[1] = (DCTELEM) DESCALE(tmp7 + z1 + z4, CONST_BITS-PASS1_BITS); + + dataptr += DCTSIZE; /* advance pointer to next row */ + } + + /* Pass 2: process columns. + * We remove the PASS1_BITS scaling, but leave the results scaled up + * by an overall factor of 8. + */ + + dataptr = data; + for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { + tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7]; + tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7]; + tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6]; + tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6]; + tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5]; + tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5]; + tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4]; + tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4]; + + /* Even part per LL&M figure 1 --- note that published figure is faulty; + * rotator "sqrt(2)*c1" should be "sqrt(2)*c6". + */ + + tmp10 = tmp0 + tmp3; + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + dataptr[DCTSIZE*0] = (DCTELEM) DESCALE(tmp10 + tmp11, PASS1_BITS); + dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp10 - tmp11, PASS1_BITS); + + z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100); + dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865), + CONST_BITS+PASS1_BITS); + dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065), + CONST_BITS+PASS1_BITS); + + /* Odd part per figure 8 --- note paper omits factor of sqrt(2). + * cK represents cos(K*pi/16). + * i0..i3 in the paper are tmp4..tmp7 here. + */ + + z1 = tmp4 + tmp7; + z2 = tmp5 + tmp6; + z3 = tmp4 + tmp6; + z4 = tmp5 + tmp7; + z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */ + + tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */ + tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */ + tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */ + tmp7 = MULTIPLY(tmp7, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */ + z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */ + z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */ + z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */ + z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */ + + z3 += z5; + z4 += z5; + + dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp4 + z1 + z3, + CONST_BITS+PASS1_BITS); + dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp5 + z2 + z4, + CONST_BITS+PASS1_BITS); + dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp6 + z2 + z3, + CONST_BITS+PASS1_BITS); + dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp7 + z1 + z4, + CONST_BITS+PASS1_BITS); + + dataptr++; /* advance pointer to next column */ + } +} + +#endif /* DCT_ISLOW_SUPPORTED */ diff --git a/src/gdcmjpeg/jidctflt.c b/src/gdcmjpeg/jidctflt.c new file mode 100644 index 00000000..0d72de89 --- /dev/null +++ b/src/gdcmjpeg/jidctflt.c @@ -0,0 +1,242 @@ +/* + * jidctflt.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains a floating-point implementation of the + * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine + * must also perform dequantization of the input coefficients. + * + * This implementation should be more accurate than either of the integer + * IDCT implementations. However, it may not give the same results on all + * machines because of differences in roundoff behavior. Speed will depend + * on the hardware's floating point capacity. + * + * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT + * on each row (or vice versa, but it's more convenient to emit a row at + * a time). Direct algorithms are also available, but they are much more + * complex and seem not to be any faster when reduced to code. + * + * This implementation is based on Arai, Agui, and Nakajima's algorithm for + * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in + * Japanese, but the algorithm is described in the Pennebaker & Mitchell + * JPEG textbook (see REFERENCES section in file README). The following code + * is based directly on figure 4-8 in P&M. + * While an 8-point DCT cannot be done in less than 11 multiplies, it is + * possible to arrange the computation so that many of the multiplies are + * simple scalings of the final outputs. These multiplies can then be + * folded into the multiplications or divisions by the JPEG quantization + * table entries. The AA&N method leaves only 5 multiplies and 29 adds + * to be done in the DCT itself. + * The primary disadvantage of this method is that with a fixed-point + * implementation, accuracy is lost due to imprecise representation of the + * scaled quantization values. However, that problem does not arise if + * we use floating point arithmetic. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef DCT_FLOAT_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* Dequantize a coefficient by multiplying it by the multiplier-table + * entry; produce a float result. + */ + +#define DEQUANTIZE(coef,quantval) (((FAST_FLOAT) (coef)) * (quantval)) + + +/* + * Perform dequantization and inverse DCT on one block of coefficients. + */ + +GLOBAL(void) +jpeg_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col) +{ + FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; + FAST_FLOAT tmp10, tmp11, tmp12, tmp13; + FAST_FLOAT z5, z10, z11, z12, z13; + JCOEFPTR inptr; + FLOAT_MULT_TYPE * quantptr; + FAST_FLOAT * wsptr; + JSAMPROW outptr; + JSAMPLE *range_limit = IDCT_range_limit(cinfo); + int ctr; + FAST_FLOAT workspace[DCTSIZE2]; /* buffers data between passes */ + SHIFT_TEMPS + + /* Pass 1: process columns from input, store into work array. */ + + inptr = coef_block; + quantptr = (FLOAT_MULT_TYPE *) compptr->dct_table; + wsptr = workspace; + for (ctr = DCTSIZE; ctr > 0; ctr--) { + /* Due to quantization, we will usually find that many of the input + * coefficients are zero, especially the AC terms. We can exploit this + * by short-circuiting the IDCT calculation for any column in which all + * the AC terms are zero. In that case each output is equal to the + * DC coefficient (with scale factor as needed). + * With typical images and quantization tables, half or more of the + * column DCT calculations can be simplified this way. + */ + + if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 && + inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 && + inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 && + inptr[DCTSIZE*7] == 0) { + /* AC terms all zero */ + FAST_FLOAT dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + + wsptr[DCTSIZE*0] = dcval; + wsptr[DCTSIZE*1] = dcval; + wsptr[DCTSIZE*2] = dcval; + wsptr[DCTSIZE*3] = dcval; + wsptr[DCTSIZE*4] = dcval; + wsptr[DCTSIZE*5] = dcval; + wsptr[DCTSIZE*6] = dcval; + wsptr[DCTSIZE*7] = dcval; + + inptr++; /* advance pointers to next column */ + quantptr++; + wsptr++; + continue; + } + + /* Even part */ + + tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]); + tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]); + tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]); + + tmp10 = tmp0 + tmp2; /* phase 3 */ + tmp11 = tmp0 - tmp2; + + tmp13 = tmp1 + tmp3; /* phases 5-3 */ + tmp12 = (tmp1 - tmp3) * ((FAST_FLOAT) 1.414213562) - tmp13; /* 2*c4 */ + + tmp0 = tmp10 + tmp13; /* phase 2 */ + tmp3 = tmp10 - tmp13; + tmp1 = tmp11 + tmp12; + tmp2 = tmp11 - tmp12; + + /* Odd part */ + + tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]); + tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]); + tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]); + tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]); + + z13 = tmp6 + tmp5; /* phase 6 */ + z10 = tmp6 - tmp5; + z11 = tmp4 + tmp7; + z12 = tmp4 - tmp7; + + tmp7 = z11 + z13; /* phase 5 */ + tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); /* 2*c4 */ + + z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */ + tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */ + tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */ + + tmp6 = tmp12 - tmp7; /* phase 2 */ + tmp5 = tmp11 - tmp6; + tmp4 = tmp10 + tmp5; + + wsptr[DCTSIZE*0] = tmp0 + tmp7; + wsptr[DCTSIZE*7] = tmp0 - tmp7; + wsptr[DCTSIZE*1] = tmp1 + tmp6; + wsptr[DCTSIZE*6] = tmp1 - tmp6; + wsptr[DCTSIZE*2] = tmp2 + tmp5; + wsptr[DCTSIZE*5] = tmp2 - tmp5; + wsptr[DCTSIZE*4] = tmp3 + tmp4; + wsptr[DCTSIZE*3] = tmp3 - tmp4; + + inptr++; /* advance pointers to next column */ + quantptr++; + wsptr++; + } + + /* Pass 2: process rows from work array, store into output array. */ + /* Note that we must descale the results by a factor of 8 == 2**3. */ + + wsptr = workspace; + for (ctr = 0; ctr < DCTSIZE; ctr++) { + outptr = output_buf[ctr] + output_col; + /* Rows of zeroes can be exploited in the same way as we did with columns. + * However, the column calculation has created many nonzero AC terms, so + * the simplification applies less often (typically 5% to 10% of the time). + * And testing floats for zero is relatively expensive, so we don't bother. + */ + + /* Even part */ + + tmp10 = wsptr[0] + wsptr[4]; + tmp11 = wsptr[0] - wsptr[4]; + + tmp13 = wsptr[2] + wsptr[6]; + tmp12 = (wsptr[2] - wsptr[6]) * ((FAST_FLOAT) 1.414213562) - tmp13; + + tmp0 = tmp10 + tmp13; + tmp3 = tmp10 - tmp13; + tmp1 = tmp11 + tmp12; + tmp2 = tmp11 - tmp12; + + /* Odd part */ + + z13 = wsptr[5] + wsptr[3]; + z10 = wsptr[5] - wsptr[3]; + z11 = wsptr[1] + wsptr[7]; + z12 = wsptr[1] - wsptr[7]; + + tmp7 = z11 + z13; + tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); + + z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */ + tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */ + tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */ + + tmp6 = tmp12 - tmp7; + tmp5 = tmp11 - tmp6; + tmp4 = tmp10 + tmp5; + + /* Final output stage: scale down by a factor of 8 and range-limit */ + + outptr[0] = range_limit[(int) DESCALE((INT32) (tmp0 + tmp7), 3) + & RANGE_MASK]; + outptr[7] = range_limit[(int) DESCALE((INT32) (tmp0 - tmp7), 3) + & RANGE_MASK]; + outptr[1] = range_limit[(int) DESCALE((INT32) (tmp1 + tmp6), 3) + & RANGE_MASK]; + outptr[6] = range_limit[(int) DESCALE((INT32) (tmp1 - tmp6), 3) + & RANGE_MASK]; + outptr[2] = range_limit[(int) DESCALE((INT32) (tmp2 + tmp5), 3) + & RANGE_MASK]; + outptr[5] = range_limit[(int) DESCALE((INT32) (tmp2 - tmp5), 3) + & RANGE_MASK]; + outptr[4] = range_limit[(int) DESCALE((INT32) (tmp3 + tmp4), 3) + & RANGE_MASK]; + outptr[3] = range_limit[(int) DESCALE((INT32) (tmp3 - tmp4), 3) + & RANGE_MASK]; + + wsptr += DCTSIZE; /* advance pointer to next row */ + } +} + +#endif /* DCT_FLOAT_SUPPORTED */ diff --git a/src/gdcmjpeg/jidctfst.c b/src/gdcmjpeg/jidctfst.c new file mode 100644 index 00000000..3245decc --- /dev/null +++ b/src/gdcmjpeg/jidctfst.c @@ -0,0 +1,368 @@ +/* + * jidctfst.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains a fast, not so accurate integer implementation of the + * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine + * must also perform dequantization of the input coefficients. + * + * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT + * on each row (or vice versa, but it's more convenient to emit a row at + * a time). Direct algorithms are also available, but they are much more + * complex and seem not to be any faster when reduced to code. + * + * This implementation is based on Arai, Agui, and Nakajima's algorithm for + * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in + * Japanese, but the algorithm is described in the Pennebaker & Mitchell + * JPEG textbook (see REFERENCES section in file README). The following code + * is based directly on figure 4-8 in P&M. + * While an 8-point DCT cannot be done in less than 11 multiplies, it is + * possible to arrange the computation so that many of the multiplies are + * simple scalings of the final outputs. These multiplies can then be + * folded into the multiplications or divisions by the JPEG quantization + * table entries. The AA&N method leaves only 5 multiplies and 29 adds + * to be done in the DCT itself. + * The primary disadvantage of this method is that with fixed-point math, + * accuracy is lost due to imprecise representation of the scaled + * quantization values. The smaller the quantization table entry, the less + * precise the scaled value, so this implementation does worse with high- + * quality-setting files than with low-quality ones. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef DCT_IFAST_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* Scaling decisions are generally the same as in the LL&M algorithm; + * see jidctint.c for more details. However, we choose to descale + * (right shift) multiplication products as soon as they are formed, + * rather than carrying additional fractional bits into subsequent additions. + * This compromises accuracy slightly, but it lets us save a few shifts. + * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples) + * everywhere except in the multiplications proper; this saves a good deal + * of work on 16-bit-int machines. + * + * The dequantized coefficients are not integers because the AA&N scaling + * factors have been incorporated. We represent them scaled up by PASS1_BITS, + * so that the first and second IDCT rounds have the same input scaling. + * For 8-bit JSAMPLEs, we choose IFAST_SCALE_BITS = PASS1_BITS so as to + * avoid a descaling shift; this compromises accuracy rather drastically + * for small quantization table entries, but it saves a lot of shifts. + * For 12-bit JSAMPLEs, there's no hope of using 16x16 multiplies anyway, + * so we use a much larger scaling factor to preserve accuracy. + * + * A final compromise is to represent the multiplicative constants to only + * 8 fractional bits, rather than 13. This saves some shifting work on some + * machines, and may also reduce the cost of multiplication (since there + * are fewer one-bits in the constants). + */ + +#if BITS_IN_JSAMPLE == 8 +#define CONST_BITS 8 +#define PASS1_BITS 2 +#else +#define CONST_BITS 8 +#define PASS1_BITS 1 /* lose a little precision to avoid overflow */ +#endif + +/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus + * causing a lot of useless floating-point operations at run time. + * To get around this we use the following pre-calculated constants. + * If you change CONST_BITS you may want to add appropriate values. + * (With a reasonable C compiler, you can just rely on the FIX() macro...) + */ + +#if CONST_BITS == 8 +#define FIX_1_082392200 ((INT32) 277) /* FIX(1.082392200) */ +#define FIX_1_414213562 ((INT32) 362) /* FIX(1.414213562) */ +#define FIX_1_847759065 ((INT32) 473) /* FIX(1.847759065) */ +#define FIX_2_613125930 ((INT32) 669) /* FIX(2.613125930) */ +#else +#define FIX_1_082392200 FIX(1.082392200) +#define FIX_1_414213562 FIX(1.414213562) +#define FIX_1_847759065 FIX(1.847759065) +#define FIX_2_613125930 FIX(2.613125930) +#endif + + +/* We can gain a little more speed, with a further compromise in accuracy, + * by omitting the addition in a descaling shift. This yields an incorrectly + * rounded result half the time... + */ + +#ifndef USE_ACCURATE_ROUNDING +#undef DESCALE +#define DESCALE(x,n) RIGHT_SHIFT(x, n) +#endif + + +/* Multiply a DCTELEM variable by an INT32 constant, and immediately + * descale to yield a DCTELEM result. + */ + +#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS)) + + +/* Dequantize a coefficient by multiplying it by the multiplier-table + * entry; produce a DCTELEM result. For 8-bit data a 16x16->16 + * multiplication will do. For 12-bit data, the multiplier table is + * declared INT32, so a 32-bit multiply will be used. + */ + +#if BITS_IN_JSAMPLE == 8 +#define DEQUANTIZE(coef,quantval) (((IFAST_MULT_TYPE) (coef)) * (quantval)) +#else +#define DEQUANTIZE(coef,quantval) \ + DESCALE((coef)*(quantval), IFAST_SCALE_BITS-PASS1_BITS) +#endif + + +/* Like DESCALE, but applies to a DCTELEM and produces an int. + * We assume that int right shift is unsigned if INT32 right shift is. + */ + +#ifdef RIGHT_SHIFT_IS_UNSIGNED +#define ISHIFT_TEMPS DCTELEM ishift_temp; +#if BITS_IN_JSAMPLE == 8 +#define DCTELEMBITS 16 /* DCTELEM may be 16 or 32 bits */ +#else +#define DCTELEMBITS 32 /* DCTELEM must be 32 bits */ +#endif +#define IRIGHT_SHIFT(x,shft) \ + ((ishift_temp = (x)) < 0 ? \ + (ishift_temp >> (shft)) | ((~((DCTELEM) 0)) << (DCTELEMBITS-(shft))) : \ + (ishift_temp >> (shft))) +#else +#define ISHIFT_TEMPS +#define IRIGHT_SHIFT(x,shft) ((x) >> (shft)) +#endif + +#ifdef USE_ACCURATE_ROUNDING +#define IDESCALE(x,n) ((int) IRIGHT_SHIFT((x) + (1 << ((n)-1)), n)) +#else +#define IDESCALE(x,n) ((int) IRIGHT_SHIFT(x, n)) +#endif + + +/* + * Perform dequantization and inverse DCT on one block of coefficients. + */ + +GLOBAL(void) +jpeg_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col) +{ + DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; + DCTELEM tmp10, tmp11, tmp12, tmp13; + DCTELEM z5, z10, z11, z12, z13; + JCOEFPTR inptr; + IFAST_MULT_TYPE * quantptr; + int * wsptr; + JSAMPROW outptr; + JSAMPLE *range_limit = IDCT_range_limit(cinfo); + int ctr; + int workspace[DCTSIZE2]; /* buffers data between passes */ + SHIFT_TEMPS /* for DESCALE */ + ISHIFT_TEMPS /* for IDESCALE */ + + /* Pass 1: process columns from input, store into work array. */ + + inptr = coef_block; + quantptr = (IFAST_MULT_TYPE *) compptr->dct_table; + wsptr = workspace; + for (ctr = DCTSIZE; ctr > 0; ctr--) { + /* Due to quantization, we will usually find that many of the input + * coefficients are zero, especially the AC terms. We can exploit this + * by short-circuiting the IDCT calculation for any column in which all + * the AC terms are zero. In that case each output is equal to the + * DC coefficient (with scale factor as needed). + * With typical images and quantization tables, half or more of the + * column DCT calculations can be simplified this way. + */ + + if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 && + inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 && + inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 && + inptr[DCTSIZE*7] == 0) { + /* AC terms all zero */ + int dcval = (int) DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + + wsptr[DCTSIZE*0] = dcval; + wsptr[DCTSIZE*1] = dcval; + wsptr[DCTSIZE*2] = dcval; + wsptr[DCTSIZE*3] = dcval; + wsptr[DCTSIZE*4] = dcval; + wsptr[DCTSIZE*5] = dcval; + wsptr[DCTSIZE*6] = dcval; + wsptr[DCTSIZE*7] = dcval; + + inptr++; /* advance pointers to next column */ + quantptr++; + wsptr++; + continue; + } + + /* Even part */ + + tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]); + tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]); + tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]); + + tmp10 = tmp0 + tmp2; /* phase 3 */ + tmp11 = tmp0 - tmp2; + + tmp13 = tmp1 + tmp3; /* phases 5-3 */ + tmp12 = MULTIPLY(tmp1 - tmp3, FIX_1_414213562) - tmp13; /* 2*c4 */ + + tmp0 = tmp10 + tmp13; /* phase 2 */ + tmp3 = tmp10 - tmp13; + tmp1 = tmp11 + tmp12; + tmp2 = tmp11 - tmp12; + + /* Odd part */ + + tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]); + tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]); + tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]); + tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]); + + z13 = tmp6 + tmp5; /* phase 6 */ + z10 = tmp6 - tmp5; + z11 = tmp4 + tmp7; + z12 = tmp4 - tmp7; + + tmp7 = z11 + z13; /* phase 5 */ + tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */ + + z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */ + tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */ + tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */ + + tmp6 = tmp12 - tmp7; /* phase 2 */ + tmp5 = tmp11 - tmp6; + tmp4 = tmp10 + tmp5; + + wsptr[DCTSIZE*0] = (int) (tmp0 + tmp7); + wsptr[DCTSIZE*7] = (int) (tmp0 - tmp7); + wsptr[DCTSIZE*1] = (int) (tmp1 + tmp6); + wsptr[DCTSIZE*6] = (int) (tmp1 - tmp6); + wsptr[DCTSIZE*2] = (int) (tmp2 + tmp5); + wsptr[DCTSIZE*5] = (int) (tmp2 - tmp5); + wsptr[DCTSIZE*4] = (int) (tmp3 + tmp4); + wsptr[DCTSIZE*3] = (int) (tmp3 - tmp4); + + inptr++; /* advance pointers to next column */ + quantptr++; + wsptr++; + } + + /* Pass 2: process rows from work array, store into output array. */ + /* Note that we must descale the results by a factor of 8 == 2**3, */ + /* and also undo the PASS1_BITS scaling. */ + + wsptr = workspace; + for (ctr = 0; ctr < DCTSIZE; ctr++) { + outptr = output_buf[ctr] + output_col; + /* Rows of zeroes can be exploited in the same way as we did with columns. + * However, the column calculation has created many nonzero AC terms, so + * the simplification applies less often (typically 5% to 10% of the time). + * On machines with very fast multiplication, it's possible that the + * test takes more time than it's worth. In that case this section + * may be commented out. + */ + +#ifndef NO_ZERO_ROW_TEST + if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && wsptr[4] == 0 && + wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) { + /* AC terms all zero */ + JSAMPLE dcval = range_limit[IDESCALE(wsptr[0], PASS1_BITS+3) + & RANGE_MASK]; + + outptr[0] = dcval; + outptr[1] = dcval; + outptr[2] = dcval; + outptr[3] = dcval; + outptr[4] = dcval; + outptr[5] = dcval; + outptr[6] = dcval; + outptr[7] = dcval; + + wsptr += DCTSIZE; /* advance pointer to next row */ + continue; + } +#endif + + /* Even part */ + + tmp10 = ((DCTELEM) wsptr[0] + (DCTELEM) wsptr[4]); + tmp11 = ((DCTELEM) wsptr[0] - (DCTELEM) wsptr[4]); + + tmp13 = ((DCTELEM) wsptr[2] + (DCTELEM) wsptr[6]); + tmp12 = MULTIPLY((DCTELEM) wsptr[2] - (DCTELEM) wsptr[6], FIX_1_414213562) + - tmp13; + + tmp0 = tmp10 + tmp13; + tmp3 = tmp10 - tmp13; + tmp1 = tmp11 + tmp12; + tmp2 = tmp11 - tmp12; + + /* Odd part */ + + z13 = (DCTELEM) wsptr[5] + (DCTELEM) wsptr[3]; + z10 = (DCTELEM) wsptr[5] - (DCTELEM) wsptr[3]; + z11 = (DCTELEM) wsptr[1] + (DCTELEM) wsptr[7]; + z12 = (DCTELEM) wsptr[1] - (DCTELEM) wsptr[7]; + + tmp7 = z11 + z13; /* phase 5 */ + tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */ + + z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */ + tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */ + tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */ + + tmp6 = tmp12 - tmp7; /* phase 2 */ + tmp5 = tmp11 - tmp6; + tmp4 = tmp10 + tmp5; + + /* Final output stage: scale down by a factor of 8 and range-limit */ + + outptr[0] = range_limit[IDESCALE(tmp0 + tmp7, PASS1_BITS+3) + & RANGE_MASK]; + outptr[7] = range_limit[IDESCALE(tmp0 - tmp7, PASS1_BITS+3) + & RANGE_MASK]; + outptr[1] = range_limit[IDESCALE(tmp1 + tmp6, PASS1_BITS+3) + & RANGE_MASK]; + outptr[6] = range_limit[IDESCALE(tmp1 - tmp6, PASS1_BITS+3) + & RANGE_MASK]; + outptr[2] = range_limit[IDESCALE(tmp2 + tmp5, PASS1_BITS+3) + & RANGE_MASK]; + outptr[5] = range_limit[IDESCALE(tmp2 - tmp5, PASS1_BITS+3) + & RANGE_MASK]; + outptr[4] = range_limit[IDESCALE(tmp3 + tmp4, PASS1_BITS+3) + & RANGE_MASK]; + outptr[3] = range_limit[IDESCALE(tmp3 - tmp4, PASS1_BITS+3) + & RANGE_MASK]; + + wsptr += DCTSIZE; /* advance pointer to next row */ + } +} + +#endif /* DCT_IFAST_SUPPORTED */ diff --git a/src/gdcmjpeg/jidctint.c b/src/gdcmjpeg/jidctint.c new file mode 100644 index 00000000..e8a8b7af --- /dev/null +++ b/src/gdcmjpeg/jidctint.c @@ -0,0 +1,389 @@ +/* + * jidctint.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains a slow-but-accurate integer implementation of the + * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine + * must also perform dequantization of the input coefficients. + * + * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT + * on each row (or vice versa, but it's more convenient to emit a row at + * a time). Direct algorithms are also available, but they are much more + * complex and seem not to be any faster when reduced to code. + * + * This implementation is based on an algorithm described in + * C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT + * Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics, + * Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991. + * The primary algorithm described there uses 11 multiplies and 29 adds. + * We use their alternate method with 12 multiplies and 32 adds. + * The advantage of this method is that no data path contains more than one + * multiplication; this allows a very simple and accurate implementation in + * scaled fixed-point arithmetic, with a minimal number of shifts. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef DCT_ISLOW_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* + * The poop on this scaling stuff is as follows: + * + * Each 1-D IDCT step produces outputs which are a factor of sqrt(N) + * larger than the true IDCT outputs. The final outputs are therefore + * a factor of N larger than desired; since N=8 this can be cured by + * a simple right shift at the end of the algorithm. The advantage of + * this arrangement is that we save two multiplications per 1-D IDCT, + * because the y0 and y4 inputs need not be divided by sqrt(N). + * + * We have to do addition and subtraction of the integer inputs, which + * is no problem, and multiplication by fractional constants, which is + * a problem to do in integer arithmetic. We multiply all the constants + * by CONST_SCALE and convert them to integer constants (thus retaining + * CONST_BITS bits of precision in the constants). After doing a + * multiplication we have to divide the product by CONST_SCALE, with proper + * rounding, to produce the correct output. This division can be done + * cheaply as a right shift of CONST_BITS bits. We postpone shifting + * as long as possible so that partial sums can be added together with + * full fractional precision. + * + * The outputs of the first pass are scaled up by PASS1_BITS bits so that + * they are represented to better-than-integral precision. These outputs + * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word + * with the recommended scaling. (To scale up 12-bit sample data further, an + * intermediate INT32 array would be needed.) + * + * To avoid overflow of the 32-bit intermediate results in pass 2, we must + * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26. Error analysis + * shows that the values given below are the most effective. + */ + +#if BITS_IN_JSAMPLE == 8 +#define CONST_BITS 13 +#define PASS1_BITS 2 +#else +#define CONST_BITS 13 +#define PASS1_BITS 1 /* lose a little precision to avoid overflow */ +#endif + +/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus + * causing a lot of useless floating-point operations at run time. + * To get around this we use the following pre-calculated constants. + * If you change CONST_BITS you may want to add appropriate values. + * (With a reasonable C compiler, you can just rely on the FIX() macro...) + */ + +#if CONST_BITS == 13 +#define FIX_0_298631336 ((INT32) 2446) /* FIX(0.298631336) */ +#define FIX_0_390180644 ((INT32) 3196) /* FIX(0.390180644) */ +#define FIX_0_541196100 ((INT32) 4433) /* FIX(0.541196100) */ +#define FIX_0_765366865 ((INT32) 6270) /* FIX(0.765366865) */ +#define FIX_0_899976223 ((INT32) 7373) /* FIX(0.899976223) */ +#define FIX_1_175875602 ((INT32) 9633) /* FIX(1.175875602) */ +#define FIX_1_501321110 ((INT32) 12299) /* FIX(1.501321110) */ +#define FIX_1_847759065 ((INT32) 15137) /* FIX(1.847759065) */ +#define FIX_1_961570560 ((INT32) 16069) /* FIX(1.961570560) */ +#define FIX_2_053119869 ((INT32) 16819) /* FIX(2.053119869) */ +#define FIX_2_562915447 ((INT32) 20995) /* FIX(2.562915447) */ +#define FIX_3_072711026 ((INT32) 25172) /* FIX(3.072711026) */ +#else +#define FIX_0_298631336 FIX(0.298631336) +#define FIX_0_390180644 FIX(0.390180644) +#define FIX_0_541196100 FIX(0.541196100) +#define FIX_0_765366865 FIX(0.765366865) +#define FIX_0_899976223 FIX(0.899976223) +#define FIX_1_175875602 FIX(1.175875602) +#define FIX_1_501321110 FIX(1.501321110) +#define FIX_1_847759065 FIX(1.847759065) +#define FIX_1_961570560 FIX(1.961570560) +#define FIX_2_053119869 FIX(2.053119869) +#define FIX_2_562915447 FIX(2.562915447) +#define FIX_3_072711026 FIX(3.072711026) +#endif + + +/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result. + * For 8-bit samples with the recommended scaling, all the variable + * and constant values involved are no more than 16 bits wide, so a + * 16x16->32 bit multiply can be used instead of a full 32x32 multiply. + * For 12-bit samples, a full 32-bit multiplication will be needed. + */ + +#if BITS_IN_JSAMPLE == 8 +#define MULTIPLY(var,const) MULTIPLY16C16(var,const) +#else +#define MULTIPLY(var,const) ((var) * (const)) +#endif + + +/* Dequantize a coefficient by multiplying it by the multiplier-table + * entry; produce an int result. In this module, both inputs and result + * are 16 bits or less, so either int or short multiply will work. + */ + +#define DEQUANTIZE(coef,quantval) (((ISLOW_MULT_TYPE) (coef)) * (quantval)) + + +/* + * Perform dequantization and inverse DCT on one block of coefficients. + */ + +GLOBAL(void) +jpeg_idct_islow (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col) +{ + INT32 tmp0, tmp1, tmp2, tmp3; + INT32 tmp10, tmp11, tmp12, tmp13; + INT32 z1, z2, z3, z4, z5; + JCOEFPTR inptr; + ISLOW_MULT_TYPE * quantptr; + int * wsptr; + JSAMPROW outptr; + JSAMPLE *range_limit = IDCT_range_limit(cinfo); + int ctr; + int workspace[DCTSIZE2]; /* buffers data between passes */ + SHIFT_TEMPS + + /* Pass 1: process columns from input, store into work array. */ + /* Note results are scaled up by sqrt(8) compared to a true IDCT; */ + /* furthermore, we scale the results by 2**PASS1_BITS. */ + + inptr = coef_block; + quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table; + wsptr = workspace; + for (ctr = DCTSIZE; ctr > 0; ctr--) { + /* Due to quantization, we will usually find that many of the input + * coefficients are zero, especially the AC terms. We can exploit this + * by short-circuiting the IDCT calculation for any column in which all + * the AC terms are zero. In that case each output is equal to the + * DC coefficient (with scale factor as needed). + * With typical images and quantization tables, half or more of the + * column DCT calculations can be simplified this way. + */ + + if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 && + inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 && + inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 && + inptr[DCTSIZE*7] == 0) { + /* AC terms all zero */ + int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS; + + wsptr[DCTSIZE*0] = dcval; + wsptr[DCTSIZE*1] = dcval; + wsptr[DCTSIZE*2] = dcval; + wsptr[DCTSIZE*3] = dcval; + wsptr[DCTSIZE*4] = dcval; + wsptr[DCTSIZE*5] = dcval; + wsptr[DCTSIZE*6] = dcval; + wsptr[DCTSIZE*7] = dcval; + + inptr++; /* advance pointers to next column */ + quantptr++; + wsptr++; + continue; + } + + /* Even part: reverse the even part of the forward DCT. */ + /* The rotator is sqrt(2)*c(-6). */ + + z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]); + z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]); + + z1 = MULTIPLY(z2 + z3, FIX_0_541196100); + tmp2 = z1 + MULTIPLY(z3, - FIX_1_847759065); + tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865); + + z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]); + + tmp0 = (z2 + z3) << CONST_BITS; + tmp1 = (z2 - z3) << CONST_BITS; + + tmp10 = tmp0 + tmp3; + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + /* Odd part per figure 8; the matrix is unitary and hence its + * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. + */ + + tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]); + tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]); + tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]); + tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]); + + z1 = tmp0 + tmp3; + z2 = tmp1 + tmp2; + z3 = tmp0 + tmp2; + z4 = tmp1 + tmp3; + z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */ + + tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */ + tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */ + tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */ + tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */ + z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */ + z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */ + z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */ + z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */ + + z3 += z5; + z4 += z5; + + tmp0 += z1 + z3; + tmp1 += z2 + z4; + tmp2 += z2 + z3; + tmp3 += z1 + z4; + + /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ + + wsptr[DCTSIZE*0] = (int) DESCALE(tmp10 + tmp3, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*7] = (int) DESCALE(tmp10 - tmp3, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*1] = (int) DESCALE(tmp11 + tmp2, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*6] = (int) DESCALE(tmp11 - tmp2, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*2] = (int) DESCALE(tmp12 + tmp1, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*5] = (int) DESCALE(tmp12 - tmp1, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*3] = (int) DESCALE(tmp13 + tmp0, CONST_BITS-PASS1_BITS); + wsptr[DCTSIZE*4] = (int) DESCALE(tmp13 - tmp0, CONST_BITS-PASS1_BITS); + + inptr++; /* advance pointers to next column */ + quantptr++; + wsptr++; + } + + /* Pass 2: process rows from work array, store into output array. */ + /* Note that we must descale the results by a factor of 8 == 2**3, */ + /* and also undo the PASS1_BITS scaling. */ + + wsptr = workspace; + for (ctr = 0; ctr < DCTSIZE; ctr++) { + outptr = output_buf[ctr] + output_col; + /* Rows of zeroes can be exploited in the same way as we did with columns. + * However, the column calculation has created many nonzero AC terms, so + * the simplification applies less often (typically 5% to 10% of the time). + * On machines with very fast multiplication, it's possible that the + * test takes more time than it's worth. In that case this section + * may be commented out. + */ + +#ifndef NO_ZERO_ROW_TEST + if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && wsptr[4] == 0 && + wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) { + /* AC terms all zero */ + JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3) + & RANGE_MASK]; + + outptr[0] = dcval; + outptr[1] = dcval; + outptr[2] = dcval; + outptr[3] = dcval; + outptr[4] = dcval; + outptr[5] = dcval; + outptr[6] = dcval; + outptr[7] = dcval; + + wsptr += DCTSIZE; /* advance pointer to next row */ + continue; + } +#endif + + /* Even part: reverse the even part of the forward DCT. */ + /* The rotator is sqrt(2)*c(-6). */ + + z2 = (INT32) wsptr[2]; + z3 = (INT32) wsptr[6]; + + z1 = MULTIPLY(z2 + z3, FIX_0_541196100); + tmp2 = z1 + MULTIPLY(z3, - FIX_1_847759065); + tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865); + + tmp0 = ((INT32) wsptr[0] + (INT32) wsptr[4]) << CONST_BITS; + tmp1 = ((INT32) wsptr[0] - (INT32) wsptr[4]) << CONST_BITS; + + tmp10 = tmp0 + tmp3; + tmp13 = tmp0 - tmp3; + tmp11 = tmp1 + tmp2; + tmp12 = tmp1 - tmp2; + + /* Odd part per figure 8; the matrix is unitary and hence its + * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. + */ + + tmp0 = (INT32) wsptr[7]; + tmp1 = (INT32) wsptr[5]; + tmp2 = (INT32) wsptr[3]; + tmp3 = (INT32) wsptr[1]; + + z1 = tmp0 + tmp3; + z2 = tmp1 + tmp2; + z3 = tmp0 + tmp2; + z4 = tmp1 + tmp3; + z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */ + + tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */ + tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */ + tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */ + tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */ + z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */ + z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */ + z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */ + z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */ + + z3 += z5; + z4 += z5; + + tmp0 += z1 + z3; + tmp1 += z2 + z4; + tmp2 += z2 + z3; + tmp3 += z1 + z4; + + /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ + + outptr[0] = range_limit[(int) DESCALE(tmp10 + tmp3, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[7] = range_limit[(int) DESCALE(tmp10 - tmp3, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[1] = range_limit[(int) DESCALE(tmp11 + tmp2, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[6] = range_limit[(int) DESCALE(tmp11 - tmp2, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[2] = range_limit[(int) DESCALE(tmp12 + tmp1, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[5] = range_limit[(int) DESCALE(tmp12 - tmp1, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[3] = range_limit[(int) DESCALE(tmp13 + tmp0, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + outptr[4] = range_limit[(int) DESCALE(tmp13 - tmp0, + CONST_BITS+PASS1_BITS+3) + & RANGE_MASK]; + + wsptr += DCTSIZE; /* advance pointer to next row */ + } +} + +#endif /* DCT_ISLOW_SUPPORTED */ diff --git a/src/gdcmjpeg/jidctred.c b/src/gdcmjpeg/jidctred.c new file mode 100644 index 00000000..5df040c1 --- /dev/null +++ b/src/gdcmjpeg/jidctred.c @@ -0,0 +1,398 @@ +/* + * jidctred.c + * + * Copyright (C) 1994-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains inverse-DCT routines that produce reduced-size output: + * either 4x4, 2x2, or 1x1 pixels from an 8x8 DCT block. + * + * The implementation is based on the Loeffler, Ligtenberg and Moschytz (LL&M) + * algorithm used in jidctint.c. We simply replace each 8-to-8 1-D IDCT step + * with an 8-to-4 step that produces the four averages of two adjacent outputs + * (or an 8-to-2 step producing two averages of four outputs, for 2x2 output). + * These steps were derived by computing the corresponding values at the end + * of the normal LL&M code, then simplifying as much as possible. + * + * 1x1 is trivial: just take the DC coefficient divided by 8. + * + * See jidctint.c for additional comments. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jdct.h" /* Private declarations for DCT subsystem */ + +#ifdef IDCT_SCALING_SUPPORTED + + +/* + * This module is specialized to the case DCTSIZE = 8. + */ + +#if DCTSIZE != 8 + Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ +#endif + + +/* Scaling is the same as in jidctint.c. */ + +#if BITS_IN_JSAMPLE == 8 +#define CONST_BITS 13 +#define PASS1_BITS 2 +#else +#define CONST_BITS 13 +#define PASS1_BITS 1 /* lose a little precision to avoid overflow */ +#endif + +/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus + * causing a lot of useless floating-point operations at run time. + * To get around this we use the following pre-calculated constants. + * If you change CONST_BITS you may want to add appropriate values. + * (With a reasonable C compiler, you can just rely on the FIX() macro...) + */ + +#if CONST_BITS == 13 +#define FIX_0_211164243 ((INT32) 1730) /* FIX(0.211164243) */ +#define FIX_0_509795579 ((INT32) 4176) /* FIX(0.509795579) */ +#define FIX_0_601344887 ((INT32) 4926) /* FIX(0.601344887) */ +#define FIX_0_720959822 ((INT32) 5906) /* FIX(0.720959822) */ +#define FIX_0_765366865 ((INT32) 6270) /* FIX(0.765366865) */ +#define FIX_0_850430095 ((INT32) 6967) /* FIX(0.850430095) */ +#define FIX_0_899976223 ((INT32) 7373) /* FIX(0.899976223) */ +#define FIX_1_061594337 ((INT32) 8697) /* FIX(1.061594337) */ +#define FIX_1_272758580 ((INT32) 10426) /* FIX(1.272758580) */ +#define FIX_1_451774981 ((INT32) 11893) /* FIX(1.451774981) */ +#define FIX_1_847759065 ((INT32) 15137) /* FIX(1.847759065) */ +#define FIX_2_172734803 ((INT32) 17799) /* FIX(2.172734803) */ +#define FIX_2_562915447 ((INT32) 20995) /* FIX(2.562915447) */ +#define FIX_3_624509785 ((INT32) 29692) /* FIX(3.624509785) */ +#else +#define FIX_0_211164243 FIX(0.211164243) +#define FIX_0_509795579 FIX(0.509795579) +#define FIX_0_601344887 FIX(0.601344887) +#define FIX_0_720959822 FIX(0.720959822) +#define FIX_0_765366865 FIX(0.765366865) +#define FIX_0_850430095 FIX(0.850430095) +#define FIX_0_899976223 FIX(0.899976223) +#define FIX_1_061594337 FIX(1.061594337) +#define FIX_1_272758580 FIX(1.272758580) +#define FIX_1_451774981 FIX(1.451774981) +#define FIX_1_847759065 FIX(1.847759065) +#define FIX_2_172734803 FIX(2.172734803) +#define FIX_2_562915447 FIX(2.562915447) +#define FIX_3_624509785 FIX(3.624509785) +#endif + + +/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result. + * For 8-bit samples with the recommended scaling, all the variable + * and constant values involved are no more than 16 bits wide, so a + * 16x16->32 bit multiply can be used instead of a full 32x32 multiply. + * For 12-bit samples, a full 32-bit multiplication will be needed. + */ + +#if BITS_IN_JSAMPLE == 8 +#define MULTIPLY(var,const) MULTIPLY16C16(var,const) +#else +#define MULTIPLY(var,const) ((var) * (const)) +#endif + + +/* Dequantize a coefficient by multiplying it by the multiplier-table + * entry; produce an int result. In this module, both inputs and result + * are 16 bits or less, so either int or short multiply will work. + */ + +#define DEQUANTIZE(coef,quantval) (((ISLOW_MULT_TYPE) (coef)) * (quantval)) + + +/* + * Perform dequantization and inverse DCT on one block of coefficients, + * producing a reduced-size 4x4 output block. + */ + +GLOBAL(void) +jpeg_idct_4x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col) +{ + INT32 tmp0, tmp2, tmp10, tmp12; + INT32 z1, z2, z3, z4; + JCOEFPTR inptr; + ISLOW_MULT_TYPE * quantptr; + int * wsptr; + JSAMPROW outptr; + JSAMPLE *range_limit = IDCT_range_limit(cinfo); + int ctr; + int workspace[DCTSIZE*4]; /* buffers data between passes */ + SHIFT_TEMPS + + /* Pass 1: process columns from input, store into work array. */ + + inptr = coef_block; + quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table; + wsptr = workspace; + for (ctr = DCTSIZE; ctr > 0; inptr++, quantptr++, wsptr++, ctr--) { + /* Don't bother to process column 4, because second pass won't use it */ + if (ctr == DCTSIZE-4) + continue; + if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 && + inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*5] == 0 && + inptr[DCTSIZE*6] == 0 && inptr[DCTSIZE*7] == 0) { + /* AC terms all zero; we need not examine term 4 for 4x4 output */ + int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS; + + wsptr[DCTSIZE*0] = dcval; + wsptr[DCTSIZE*1] = dcval; + wsptr[DCTSIZE*2] = dcval; + wsptr[DCTSIZE*3] = dcval; + + continue; + } + + /* Even part */ + + tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + tmp0 <<= (CONST_BITS+1); + + z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]); + z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]); + + tmp2 = MULTIPLY(z2, FIX_1_847759065) + MULTIPLY(z3, - FIX_0_765366865); + + tmp10 = tmp0 + tmp2; + tmp12 = tmp0 - tmp2; + + /* Odd part */ + + z1 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]); + z2 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]); + z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]); + z4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]); + + tmp0 = MULTIPLY(z1, - FIX_0_211164243) /* sqrt(2) * (c3-c1) */ + + MULTIPLY(z2, FIX_1_451774981) /* sqrt(2) * (c3+c7) */ + + MULTIPLY(z3, - FIX_2_172734803) /* sqrt(2) * (-c1-c5) */ + + MULTIPLY(z4, FIX_1_061594337); /* sqrt(2) * (c5+c7) */ + + tmp2 = MULTIPLY(z1, - FIX_0_509795579) /* sqrt(2) * (c7-c5) */ + + MULTIPLY(z2, - FIX_0_601344887) /* sqrt(2) * (c5-c1) */ + + MULTIPLY(z3, FIX_0_899976223) /* sqrt(2) * (c3-c7) */ + + MULTIPLY(z4, FIX_2_562915447); /* sqrt(2) * (c1+c3) */ + + /* Final output stage */ + + wsptr[DCTSIZE*0] = (int) DESCALE(tmp10 + tmp2, CONST_BITS-PASS1_BITS+1); + wsptr[DCTSIZE*3] = (int) DESCALE(tmp10 - tmp2, CONST_BITS-PASS1_BITS+1); + wsptr[DCTSIZE*1] = (int) DESCALE(tmp12 + tmp0, CONST_BITS-PASS1_BITS+1); + wsptr[DCTSIZE*2] = (int) DESCALE(tmp12 - tmp0, CONST_BITS-PASS1_BITS+1); + } + + /* Pass 2: process 4 rows from work array, store into output array. */ + + wsptr = workspace; + for (ctr = 0; ctr < 4; ctr++) { + outptr = output_buf[ctr] + output_col; + /* It's not clear whether a zero row test is worthwhile here ... */ + +#ifndef NO_ZERO_ROW_TEST + if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && + wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) { + /* AC terms all zero */ + JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3) + & RANGE_MASK]; + + outptr[0] = dcval; + outptr[1] = dcval; + outptr[2] = dcval; + outptr[3] = dcval; + + wsptr += DCTSIZE; /* advance pointer to next row */ + continue; + } +#endif + + /* Even part */ + + tmp0 = ((INT32) wsptr[0]) << (CONST_BITS+1); + + tmp2 = MULTIPLY((INT32) wsptr[2], FIX_1_847759065) + + MULTIPLY((INT32) wsptr[6], - FIX_0_765366865); + + tmp10 = tmp0 + tmp2; + tmp12 = tmp0 - tmp2; + + /* Odd part */ + + z1 = (INT32) wsptr[7]; + z2 = (INT32) wsptr[5]; + z3 = (INT32) wsptr[3]; + z4 = (INT32) wsptr[1]; + + tmp0 = MULTIPLY(z1, - FIX_0_211164243) /* sqrt(2) * (c3-c1) */ + + MULTIPLY(z2, FIX_1_451774981) /* sqrt(2) * (c3+c7) */ + + MULTIPLY(z3, - FIX_2_172734803) /* sqrt(2) * (-c1-c5) */ + + MULTIPLY(z4, FIX_1_061594337); /* sqrt(2) * (c5+c7) */ + + tmp2 = MULTIPLY(z1, - FIX_0_509795579) /* sqrt(2) * (c7-c5) */ + + MULTIPLY(z2, - FIX_0_601344887) /* sqrt(2) * (c5-c1) */ + + MULTIPLY(z3, FIX_0_899976223) /* sqrt(2) * (c3-c7) */ + + MULTIPLY(z4, FIX_2_562915447); /* sqrt(2) * (c1+c3) */ + + /* Final output stage */ + + outptr[0] = range_limit[(int) DESCALE(tmp10 + tmp2, + CONST_BITS+PASS1_BITS+3+1) + & RANGE_MASK]; + outptr[3] = range_limit[(int) DESCALE(tmp10 - tmp2, + CONST_BITS+PASS1_BITS+3+1) + & RANGE_MASK]; + outptr[1] = range_limit[(int) DESCALE(tmp12 + tmp0, + CONST_BITS+PASS1_BITS+3+1) + & RANGE_MASK]; + outptr[2] = range_limit[(int) DESCALE(tmp12 - tmp0, + CONST_BITS+PASS1_BITS+3+1) + & RANGE_MASK]; + + wsptr += DCTSIZE; /* advance pointer to next row */ + } +} + + +/* + * Perform dequantization and inverse DCT on one block of coefficients, + * producing a reduced-size 2x2 output block. + */ + +GLOBAL(void) +jpeg_idct_2x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col) +{ + INT32 tmp0, tmp10, z1; + JCOEFPTR inptr; + ISLOW_MULT_TYPE * quantptr; + int * wsptr; + JSAMPROW outptr; + JSAMPLE *range_limit = IDCT_range_limit(cinfo); + int ctr; + int workspace[DCTSIZE*2]; /* buffers data between passes */ + SHIFT_TEMPS + + /* Pass 1: process columns from input, store into work array. */ + + inptr = coef_block; + quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table; + wsptr = workspace; + for (ctr = DCTSIZE; ctr > 0; inptr++, quantptr++, wsptr++, ctr--) { + /* Don't bother to process columns 2,4,6 */ + if (ctr == DCTSIZE-2 || ctr == DCTSIZE-4 || ctr == DCTSIZE-6) + continue; + if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*3] == 0 && + inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*7] == 0) { + /* AC terms all zero; we need not examine terms 2,4,6 for 2x2 output */ + int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS; + + wsptr[DCTSIZE*0] = dcval; + wsptr[DCTSIZE*1] = dcval; + + continue; + } + + /* Even part */ + + z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); + tmp10 = z1 << (CONST_BITS+2); + + /* Odd part */ + + z1 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]); + tmp0 = MULTIPLY(z1, - FIX_0_720959822); /* sqrt(2) * (c7-c5+c3-c1) */ + z1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]); + tmp0 += MULTIPLY(z1, FIX_0_850430095); /* sqrt(2) * (-c1+c3+c5+c7) */ + z1 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]); + tmp0 += MULTIPLY(z1, - FIX_1_272758580); /* sqrt(2) * (-c1+c3-c5-c7) */ + z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]); + tmp0 += MULTIPLY(z1, FIX_3_624509785); /* sqrt(2) * (c1+c3+c5+c7) */ + + /* Final output stage */ + + wsptr[DCTSIZE*0] = (int) DESCALE(tmp10 + tmp0, CONST_BITS-PASS1_BITS+2); + wsptr[DCTSIZE*1] = (int) DESCALE(tmp10 - tmp0, CONST_BITS-PASS1_BITS+2); + } + + /* Pass 2: process 2 rows from work array, store into output array. */ + + wsptr = workspace; + for (ctr = 0; ctr < 2; ctr++) { + outptr = output_buf[ctr] + output_col; + /* It's not clear whether a zero row test is worthwhile here ... */ + +#ifndef NO_ZERO_ROW_TEST + if (wsptr[1] == 0 && wsptr[3] == 0 && wsptr[5] == 0 && wsptr[7] == 0) { + /* AC terms all zero */ + JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3) + & RANGE_MASK]; + + outptr[0] = dcval; + outptr[1] = dcval; + + wsptr += DCTSIZE; /* advance pointer to next row */ + continue; + } +#endif + + /* Even part */ + + tmp10 = ((INT32) wsptr[0]) << (CONST_BITS+2); + + /* Odd part */ + + tmp0 = MULTIPLY((INT32) wsptr[7], - FIX_0_720959822) /* sqrt(2) * (c7-c5+c3-c1) */ + + MULTIPLY((INT32) wsptr[5], FIX_0_850430095) /* sqrt(2) * (-c1+c3+c5+c7) */ + + MULTIPLY((INT32) wsptr[3], - FIX_1_272758580) /* sqrt(2) * (-c1+c3-c5-c7) */ + + MULTIPLY((INT32) wsptr[1], FIX_3_624509785); /* sqrt(2) * (c1+c3+c5+c7) */ + + /* Final output stage */ + + outptr[0] = range_limit[(int) DESCALE(tmp10 + tmp0, + CONST_BITS+PASS1_BITS+3+2) + & RANGE_MASK]; + outptr[1] = range_limit[(int) DESCALE(tmp10 - tmp0, + CONST_BITS+PASS1_BITS+3+2) + & RANGE_MASK]; + + wsptr += DCTSIZE; /* advance pointer to next row */ + } +} + + +/* + * Perform dequantization and inverse DCT on one block of coefficients, + * producing a reduced-size 1x1 output block. + */ + +GLOBAL(void) +jpeg_idct_1x1 (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col) +{ + int dcval; + ISLOW_MULT_TYPE * quantptr; + JSAMPLE *range_limit = IDCT_range_limit(cinfo); + SHIFT_TEMPS + + /* We hardly need an inverse DCT routine for this: just take the + * average pixel value, which is one-eighth of the DC coefficient. + */ + quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table; + dcval = DEQUANTIZE(coef_block[0], quantptr[0]); + dcval = (int) DESCALE((INT32) dcval, 3); + + output_buf[0][output_col] = range_limit[dcval & RANGE_MASK]; +} + +#endif /* IDCT_SCALING_SUPPORTED */ diff --git a/src/gdcmjpeg/jinclude.h b/src/gdcmjpeg/jinclude.h new file mode 100644 index 00000000..5d554f37 --- /dev/null +++ b/src/gdcmjpeg/jinclude.h @@ -0,0 +1,91 @@ +/* + * jinclude.h + * + * Copyright (C) 1991-1994, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file exists to provide a single place to fix any problems with + * including the wrong system include files. (Common problems are taken + * care of by the standard jconfig symbols, but on really weird systems + * you may have to edit this file.) + * + * NOTE: this file is NOT intended to be included by applications using the + * JPEG library. Most applications need only include jpeglib.h. + */ + + +/* Include auto-config file to find out which system include files we need. */ + +#include "jconfig.h" /* auto configuration options */ +#define JCONFIG_INCLUDED /* so that jpeglib.h doesn't do it again */ + +/* + * We need the NULL macro and size_t typedef. + * On an ANSI-conforming system it is sufficient to include . + * Otherwise, we get them from or ; we may have to + * pull in as well. + * Note that the core JPEG library does not require ; + * only the default error handler and data source/destination modules do. + * But we must pull it in because of the references to FILE in jpeglib.h. + * You can remove those references if you want to compile without . + */ + +#ifdef HAVE_STDDEF_H +#include +#endif + +#ifdef HAVE_STDLIB_H +#include +#endif + +#ifdef NEED_SYS_TYPES_H +#include +#endif + +#include + +/* + * We need memory copying and zeroing functions, plus strncpy(). + * ANSI and System V implementations declare these in . + * BSD doesn't have the mem() functions, but it does have bcopy()/bzero(). + * Some systems may declare memset and memcpy in . + * + * NOTE: we assume the size parameters to these functions are of type size_t. + * Change the casts in these macros if not! + */ + +#ifdef NEED_BSD_STRINGS + +#include +#define MEMZERO(target,size) bzero((void *)(target), (size_t)(size)) +#define MEMCOPY(dest,src,size) bcopy((const void *)(src), (void *)(dest), (size_t)(size)) + +#else /* not BSD, assume ANSI/SysV string lib */ + +#include +#define MEMZERO(target,size) memset((void *)(target), 0, (size_t)(size)) +#define MEMCOPY(dest,src,size) memcpy((void *)(dest), (const void *)(src), (size_t)(size)) + +#endif + +/* + * In ANSI C, and indeed any rational implementation, size_t is also the + * type returned by sizeof(). However, it seems there are some irrational + * implementations out there, in which sizeof() returns an int even though + * size_t is defined as long or unsigned long. To ensure consistent results + * we always use this SIZEOF() macro in place of using sizeof() directly. + */ + +#define SIZEOF(object) ((size_t) sizeof(object)) + +/* + * The modules that use fread() and fwrite() always invoke them through + * these macros. On some systems you may need to twiddle the argument casts. + * CAUTION: argument order is different from underlying functions! + */ + +#define JFREAD(file,buf,sizeofbuf) \ + ((size_t) fread((void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file))) +#define JFWRITE(file,buf,sizeofbuf) \ + ((size_t) fwrite((const void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file))) diff --git a/src/gdcmjpeg/jlossls.h b/src/gdcmjpeg/jlossls.h new file mode 100644 index 00000000..2feccd6d --- /dev/null +++ b/src/gdcmjpeg/jlossls.h @@ -0,0 +1,151 @@ +/* + * jlossls.h + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This include file contains common declarations for the lossless JPEG + * codec modules. + */ + +#ifndef JLOSSLS_H +#define JLOSSLS_H + + +/* + * Table H.1: Predictors for lossless coding. + */ + +#define PREDICTOR1 Ra +#define PREDICTOR2 Rb +#define PREDICTOR3 Rc +#define PREDICTOR4 (int) ((INT32) Ra + (INT32) Rb - (INT32) Rc) +#define PREDICTOR5 (int) ((INT32) Ra + RIGHT_SHIFT((INT32) Rb - (INT32) Rc, 1)) +#define PREDICTOR6 (int) ((INT32) Rb + RIGHT_SHIFT((INT32) Ra - (INT32) Rc, 1)) +#define PREDICTOR7 (int) RIGHT_SHIFT((INT32) Ra + (INT32) Rb, 1) + + +typedef JMETHOD(void, predict_difference_method_ptr, + (j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW prev_row, + JDIFFROW diff_buf, JDIMENSION width)); + +typedef JMETHOD(void, scaler_method_ptr, + (j_compress_ptr cinfo, int ci, + JSAMPROW input_buf, JSAMPROW output_buf, + JDIMENSION width)); + +/* Lossless-specific compression codec (compressor proper) */ +typedef struct { + struct jpeg_c_codec pub; /* public fields */ + + + /* Difference buffer control */ + JMETHOD(void, diff_start_pass, (j_compress_ptr cinfo, + J_BUF_MODE pass_mode)); + + /* Pointer to data which is private to diff controller */ + void *diff_private; + + + /* Entropy encoding */ + JMETHOD(JDIMENSION, entropy_encode_mcus, (j_compress_ptr cinfo, + JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, + JDIMENSION MCU_col_num, + JDIMENSION nMCU)); + + /* Pointer to data which is private to entropy module */ + void *entropy_private; + + + /* Prediction, differencing */ + JMETHOD(void, predict_start_pass, (j_compress_ptr cinfo)); + + /* It is useful to allow each component to have a separate diff method. */ + predict_difference_method_ptr predict_difference[MAX_COMPONENTS]; + + /* Pointer to data which is private to predictor module */ + void *pred_private; + + /* Sample scaling */ + JMETHOD(void, scaler_start_pass, (j_compress_ptr cinfo)); + JMETHOD(void, scaler_scale, (j_compress_ptr cinfo, + JSAMPROW input_buf, JSAMPROW output_buf, + JDIMENSION width)); + + /* Pointer to data which is private to scaler module */ + void *scaler_private; + +} jpeg_lossless_c_codec; + +typedef jpeg_lossless_c_codec * j_lossless_c_ptr; + + +typedef JMETHOD(void, predict_undifference_method_ptr, + (j_decompress_ptr cinfo, int comp_index, + JDIFFROW diff_buf, JDIFFROW prev_row, + JDIFFROW undiff_buf, JDIMENSION width)); + +/* Lossless-specific decompression codec (decompressor proper) */ +typedef struct { + struct jpeg_d_codec pub; /* public fields */ + + + /* Difference buffer control */ + JMETHOD(void, diff_start_input_pass, (j_decompress_ptr cinfo)); + + /* Pointer to data which is private to diff controller */ + void *diff_private; + + + /* Entropy decoding */ + JMETHOD(void, entropy_start_pass, (j_decompress_ptr cinfo)); + JMETHOD(boolean, entropy_process_restart, (j_decompress_ptr cinfo)); + JMETHOD(JDIMENSION, entropy_decode_mcus, (j_decompress_ptr cinfo, + JDIFFIMAGE diff_buf, + JDIMENSION MCU_row_num, + JDIMENSION MCU_col_num, + JDIMENSION nMCU)); + + /* Pointer to data which is private to entropy module */ + void *entropy_private; + + + /* Prediction, undifferencing */ + JMETHOD(void, predict_start_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, predict_process_restart, (j_decompress_ptr cinfo)); + + /* It is useful to allow each component to have a separate undiff method. */ + predict_undifference_method_ptr predict_undifference[MAX_COMPONENTS]; + + /* Pointer to data which is private to predictor module */ + void *pred_private; + + /* Sample scaling */ + JMETHOD(void, scaler_start_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, scaler_scale, (j_decompress_ptr cinfo, + JDIFFROW diff_buf, JSAMPROW output_buf, + JDIMENSION width)); + + /* Pointer to data which is private to scaler module */ + void *scaler_private; + +} jpeg_lossless_d_codec; + +typedef jpeg_lossless_d_codec * j_lossless_d_ptr; + + +/* Compression module initialization routines */ +EXTERN(void) jinit_lossless_c_codec JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_lhuff_encoder JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_differencer JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_c_scaler JPP((j_compress_ptr cinfo)); +/* Decompression module initialization routines */ +EXTERN(void) jinit_lossless_d_codec JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_lhuff_decoder JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_undifferencer JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_d_scaler JPP((j_decompress_ptr cinfo)); + +#endif /* JLOSSLS_H */ diff --git a/src/gdcmjpeg/jlossy.h b/src/gdcmjpeg/jlossy.h new file mode 100644 index 00000000..83c43f04 --- /dev/null +++ b/src/gdcmjpeg/jlossy.h @@ -0,0 +1,120 @@ +/* + * jlossy.h + * + * Copyright (C) 1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This include file contains common declarations for the lossy (DCT-based) + * JPEG codec modules. + */ + +#ifndef JLOSSY_H +#define JLOSSY_H + + +/* Lossy-specific compression codec (compressor proper) */ +typedef struct { + struct jpeg_c_codec pub; /* public fields */ + + + /* Coefficient buffer control */ + JMETHOD(void, coef_start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); + /* JMETHOD(boolean, coef_compress_data, (j_compress_ptr cinfo, + JSAMPIMAGE input_buf));*/ + + /* Pointer to data which is private to coef module */ + void *coef_private; + + + /* Forward DCT (also controls coefficient quantization) */ + JMETHOD(void, fdct_start_pass, (j_compress_ptr cinfo)); + /* perhaps this should be an array??? */ + JMETHOD(void, fdct_forward_DCT, (j_compress_ptr cinfo, + jpeg_component_info * compptr, + JSAMPARRAY sample_data, JBLOCKROW coef_blocks, + JDIMENSION start_row, JDIMENSION start_col, + JDIMENSION num_blocks)); + + /* Pointer to data which is private to fdct module */ + void *fdct_private; + + + /* Entropy encoding */ + JMETHOD(boolean, entropy_encode_mcu, (j_compress_ptr cinfo, + JBLOCKROW *MCU_data)); + + /* Pointer to data which is private to entropy module */ + void *entropy_private; + +} jpeg_lossy_c_codec; + +typedef jpeg_lossy_c_codec * j_lossy_c_ptr; + + + +typedef JMETHOD(void, inverse_DCT_method_ptr, + (j_decompress_ptr cinfo, jpeg_component_info * compptr, + JCOEFPTR coef_block, + JSAMPARRAY output_buf, JDIMENSION output_col)); + +/* Lossy-specific decompression codec (decompressor proper) */ +typedef struct { + struct jpeg_d_codec pub; /* public fields */ + + + /* Coefficient buffer control */ + JMETHOD(void, coef_start_input_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, coef_start_output_pass, (j_decompress_ptr cinfo)); + + /* Pointer to array of coefficient virtual arrays, or NULL if none */ + jvirt_barray_ptr *coef_arrays; + + /* Pointer to data which is private to coef module */ + void *coef_private; + + + /* Entropy decoding */ + JMETHOD(void, entropy_start_pass, (j_decompress_ptr cinfo)); + JMETHOD(boolean, entropy_decode_mcu, (j_decompress_ptr cinfo, + JBLOCKROW *MCU_data)); + + /* This is here to share code between baseline and progressive decoders; */ + /* other modules probably should not use it */ + boolean entropy_insufficient_data; /* set TRUE after emitting warning */ + + /* Pointer to data which is private to entropy module */ + void *entropy_private; + + + /* Inverse DCT (also performs dequantization) */ + JMETHOD(void, idct_start_pass, (j_decompress_ptr cinfo)); + + /* It is useful to allow each component to have a separate IDCT method. */ + inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS]; + + /* Pointer to data which is private to idct module */ + void *idct_private; + +} jpeg_lossy_d_codec; + +typedef jpeg_lossy_d_codec * j_lossy_d_ptr; + + +/* Compression module initialization routines */ +EXTERN(void) jinit_lossy_c_codec JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo, + boolean need_full_buffer)); +EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_shuff_encoder JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo)); + +/* Decompression module initialization routines */ +EXTERN(void) jinit_lossy_d_codec JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo, + boolean need_full_buffer)); +EXTERN(void) jinit_shuff_decoder JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo)); + +#endif /* JLOSSY_H */ diff --git a/src/gdcmjpeg/jmemmgr.c b/src/gdcmjpeg/jmemmgr.c new file mode 100644 index 00000000..7e2db9d9 --- /dev/null +++ b/src/gdcmjpeg/jmemmgr.c @@ -0,0 +1,1174 @@ +/* + * jmemmgr.c + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains the JPEG system-independent memory management + * routines. This code is usable across a wide variety of machines; most + * of the system dependencies have been isolated in a separate file. + * The major functions provided here are: + * * pool-based allocation and freeing of memory; + * * policy decisions about how to divide available memory among the + * virtual arrays; + * * control logic for swapping virtual arrays between main memory and + * backing storage. + * The separate system-dependent file provides the actual backing-storage + * access code, and it contains the policy decision about how much total + * main memory to use. + * This file is system-dependent in the sense that some of its functions + * are unnecessary in some systems. For example, if there is enough virtual + * memory so that backing storage will never be used, much of the virtual + * array control logic could be removed. (Of course, if you have that much + * memory then you shouldn't care about a little bit of unused code...) + */ + +#define JPEG_INTERNALS +#define AM_MEMORY_MANAGER /* we define jvirt_Xarray_control structs */ +#include "jinclude.h" +#include "jpeglib.h" +#include "jmemsys.h" /* import the system-dependent declarations */ + +#ifndef NO_GETENV +#ifndef HAVE_STDLIB_H /* should declare getenv() */ +extern char * getenv JPP((const char * name)); +#endif +#endif + + +/* + * Some important notes: + * The allocation routines provided here must never return NULL. + * They should exit to error_exit if unsuccessful. + * + * It's not a good idea to try to merge the sarray, barray and darray + * routines, even though they are textually almost the same, because + * samples are usually stored as bytes while coefficients and differenced + * are shorts or ints. Thus, in machines where byte pointers have a + * different representation from word pointers, the resulting machine + * code could not be the same. + */ + + +/* + * Many machines require storage alignment: longs must start on 4-byte + * boundaries, doubles on 8-byte boundaries, etc. On such machines, malloc() + * always returns pointers that are multiples of the worst-case alignment + * requirement, and we had better do so too. + * There isn't any really portable way to determine the worst-case alignment + * requirement. This module assumes that the alignment requirement is + * multiples of sizeof(ALIGN_TYPE). + * By default, we define ALIGN_TYPE as double. This is necessary on some + * workstations (where doubles really do need 8-byte alignment) and will work + * fine on nearly everything. If your machine has lesser alignment needs, + * you can save a few bytes by making ALIGN_TYPE smaller. + * The only place I know of where this will NOT work is certain Macintosh + * 680x0 compilers that define double as a 10-byte IEEE extended float. + * Doing 10-byte alignment is counterproductive because longwords won't be + * aligned well. Put "#define ALIGN_TYPE long" in jconfig.h if you have + * such a compiler. + */ + +#ifndef ALIGN_TYPE /* so can override from jconfig.h */ +#define ALIGN_TYPE double +#endif + + +/* + * We allocate objects from "pools", where each pool is gotten with a single + * request to jpeg_get_small() or jpeg_get_large(). There is no per-object + * overhead within a pool, except for alignment padding. Each pool has a + * header with a link to the next pool of the same class. + * Small and large pool headers are identical except that the latter's + * link pointer must be FAR on 80x86 machines. + * Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE + * field. This forces the compiler to make SIZEOF(small_pool_hdr) a multiple + * of the alignment requirement of ALIGN_TYPE. + */ + +typedef union small_pool_struct * small_pool_ptr; + +typedef union small_pool_struct { + struct { + small_pool_ptr next; /* next in list of pools */ + size_t bytes_used; /* how many bytes already used within pool */ + size_t bytes_left; /* bytes still available in this pool */ + } hdr; + ALIGN_TYPE dummy; /* included in union to ensure alignment */ +} small_pool_hdr; + +typedef union large_pool_struct FAR * large_pool_ptr; + +typedef union large_pool_struct { + struct { + large_pool_ptr next; /* next in list of pools */ + size_t bytes_used; /* how many bytes already used within pool */ + size_t bytes_left; /* bytes still available in this pool */ + } hdr; + ALIGN_TYPE dummy; /* included in union to ensure alignment */ +} large_pool_hdr; + + +/* + * Here is the full definition of a memory manager object. + */ + +typedef struct { + struct jpeg_memory_mgr pub; /* public fields */ + + /* Each pool identifier (lifetime class) names a linked list of pools. */ + small_pool_ptr small_list[JPOOL_NUMPOOLS]; + large_pool_ptr large_list[JPOOL_NUMPOOLS]; + + /* Since we only have one lifetime class of virtual arrays, only one + * linked list is necessary (for each datatype). Note that the virtual + * array control blocks being linked together are actually stored somewhere + * in the small-pool list. + */ + jvirt_sarray_ptr virt_sarray_list; + jvirt_barray_ptr virt_barray_list; + + /* This counts total space obtained from jpeg_get_small/large */ + long total_space_allocated; + + /* alloc_sarray and alloc_barray set this value for use by virtual + * array routines. + */ + JDIMENSION last_rowsperchunk; /* from most recent alloc_sarray/barray */ +} my_memory_mgr; + +typedef my_memory_mgr * my_mem_ptr; + + +/* + * The control blocks for virtual arrays. + * Note that these blocks are allocated in the "small" pool area. + * System-dependent info for the associated backing store (if any) is hidden + * inside the backing_store_info struct. + */ + +struct jvirt_sarray_control { + JSAMPARRAY mem_buffer; /* => the in-memory buffer */ + JDIMENSION rows_in_array; /* total virtual array height */ + JDIMENSION samplesperrow; /* width of array (and of memory buffer) */ + JDIMENSION maxaccess; /* max rows accessed by access_virt_sarray */ + JDIMENSION rows_in_mem; /* height of memory buffer */ + JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */ + JDIMENSION cur_start_row; /* first logical row # in the buffer */ + JDIMENSION first_undef_row; /* row # of first uninitialized row */ + boolean pre_zero; /* pre-zero mode requested? */ + boolean dirty; /* do current buffer contents need written? */ + boolean b_s_open; /* is backing-store data valid? */ + jvirt_sarray_ptr next; /* link to next virtual sarray control block */ + backing_store_info b_s_info; /* System-dependent control info */ +}; + +struct jvirt_barray_control { + JBLOCKARRAY mem_buffer; /* => the in-memory buffer */ + JDIMENSION rows_in_array; /* total virtual array height */ + JDIMENSION blocksperrow; /* width of array (and of memory buffer) */ + JDIMENSION maxaccess; /* max rows accessed by access_virt_barray */ + JDIMENSION rows_in_mem; /* height of memory buffer */ + JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */ + JDIMENSION cur_start_row; /* first logical row # in the buffer */ + JDIMENSION first_undef_row; /* row # of first uninitialized row */ + boolean pre_zero; /* pre-zero mode requested? */ + boolean dirty; /* do current buffer contents need written? */ + boolean b_s_open; /* is backing-store data valid? */ + jvirt_barray_ptr next; /* link to next virtual barray control block */ + backing_store_info b_s_info; /* System-dependent control info */ +}; + + +#ifdef MEM_STATS /* optional extra stuff for statistics */ + +LOCAL(void) +print_mem_stats (j_common_ptr cinfo, int pool_id) +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + small_pool_ptr shdr_ptr; + large_pool_ptr lhdr_ptr; + + /* Since this is only a debugging stub, we can cheat a little by using + * fprintf directly rather than going through the trace message code. + * This is helpful because message parm array can't handle longs. + */ + fprintf(stderr, "Freeing pool %d, total space = %ld\n", + pool_id, mem->total_space_allocated); + + for (lhdr_ptr = mem->large_list[pool_id]; lhdr_ptr != NULL; + lhdr_ptr = lhdr_ptr->hdr.next) { + fprintf(stderr, " Large chunk used %ld\n", + (long) lhdr_ptr->hdr.bytes_used); + } + + for (shdr_ptr = mem->small_list[pool_id]; shdr_ptr != NULL; + shdr_ptr = shdr_ptr->hdr.next) { + fprintf(stderr, " Small chunk used %ld free %ld\n", + (long) shdr_ptr->hdr.bytes_used, + (long) shdr_ptr->hdr.bytes_left); + } +} + +#endif /* MEM_STATS */ + + +LOCAL(void) +out_of_memory (j_common_ptr cinfo, int which) +/* Report an out-of-memory error and stop execution */ +/* If we compiled MEM_STATS support, report alloc requests before dying */ +{ +#ifdef MEM_STATS + cinfo->err->trace_level = 2; /* force self_destruct to report stats */ +#endif + ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, which); +} + + +/* + * Allocation of "small" objects. + * + * For these, we use pooled storage. When a new pool must be created, + * we try to get enough space for the current request plus a "slop" factor, + * where the slop will be the amount of leftover space in the new pool. + * The speed vs. space tradeoff is largely determined by the slop values. + * A different slop value is provided for each pool class (lifetime), + * and we also distinguish the first pool of a class from later ones. + * NOTE: the values given work fairly well on both 16- and 32-bit-int + * machines, but may be too small if longs are 64 bits or more. + */ + +static const size_t first_pool_slop[JPOOL_NUMPOOLS] = +{ + 1600, /* first PERMANENT pool */ + 16000 /* first IMAGE pool */ +}; + +static const size_t extra_pool_slop[JPOOL_NUMPOOLS] = +{ + 0, /* additional PERMANENT pools */ + 5000 /* additional IMAGE pools */ +}; + +#define MIN_SLOP 50 /* greater than 0 to avoid futile looping */ + + +METHODDEF(void *) +alloc_small (j_common_ptr cinfo, int pool_id, size_t sizeofobject) +/* Allocate a "small" object */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + small_pool_ptr hdr_ptr, prev_hdr_ptr; + char * data_ptr; + size_t odd_bytes, min_request, slop; + + /* Check for unsatisfiable request (do now to ensure no overflow below) */ + if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(small_pool_hdr))) + out_of_memory(cinfo, 1); /* request exceeds malloc's ability */ + + /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */ + odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE); + if (odd_bytes > 0) + sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes; + + /* See if space is available in any existing pool */ + if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS) + ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */ + prev_hdr_ptr = NULL; + hdr_ptr = mem->small_list[pool_id]; + while (hdr_ptr != NULL) { + if (hdr_ptr->hdr.bytes_left >= sizeofobject) + break; /* found pool with enough space */ + prev_hdr_ptr = hdr_ptr; + hdr_ptr = hdr_ptr->hdr.next; + } + + /* Time to make a new pool? */ + if (hdr_ptr == NULL) { + /* min_request is what we need now, slop is what will be leftover */ + min_request = sizeofobject + SIZEOF(small_pool_hdr); + if (prev_hdr_ptr == NULL) /* first pool in class? */ + slop = first_pool_slop[pool_id]; + else + slop = extra_pool_slop[pool_id]; + /* Don't ask for more than MAX_ALLOC_CHUNK */ + if (slop > (size_t) (MAX_ALLOC_CHUNK-min_request)) + slop = (size_t) (MAX_ALLOC_CHUNK-min_request); + /* Try to get space, if fail reduce slop and try again */ + for (;;) { + hdr_ptr = (small_pool_ptr) jpeg_get_small(cinfo, min_request + slop); + if (hdr_ptr != NULL) + break; + slop /= 2; + if (slop < MIN_SLOP) /* give up when it gets real small */ + out_of_memory(cinfo, 2); /* jpeg_get_small failed */ + } + mem->total_space_allocated += min_request + slop; + /* Success, initialize the new pool header and add to end of list */ + hdr_ptr->hdr.next = NULL; + hdr_ptr->hdr.bytes_used = 0; + hdr_ptr->hdr.bytes_left = sizeofobject + slop; + if (prev_hdr_ptr == NULL) /* first pool in class? */ + mem->small_list[pool_id] = hdr_ptr; + else + prev_hdr_ptr->hdr.next = hdr_ptr; + } + + /* OK, allocate the object from the current pool */ + data_ptr = (char *) (hdr_ptr + 1); /* point to first data byte in pool */ + data_ptr += hdr_ptr->hdr.bytes_used; /* point to place for object */ + hdr_ptr->hdr.bytes_used += sizeofobject; + hdr_ptr->hdr.bytes_left -= sizeofobject; + + return (void *) data_ptr; +} + + +/* + * Allocation of "large" objects. + * + * The external semantics of these are the same as "small" objects, + * except that FAR pointers are used on 80x86. However the pool + * management heuristics are quite different. We assume that each + * request is large enough that it may as well be passed directly to + * jpeg_get_large; the pool management just links everything together + * so that we can free it all on demand. + * Note: the major use of "large" objects is in JSAMPARRAY and JBLOCKARRAY + * structures. The routines that create these structures (see below) + * deliberately bunch rows together to ensure a large request size. + */ + +METHODDEF(void FAR *) +alloc_large (j_common_ptr cinfo, int pool_id, size_t sizeofobject) +/* Allocate a "large" object */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + large_pool_ptr hdr_ptr; + size_t odd_bytes; + + /* Check for unsatisfiable request (do now to ensure no overflow below) */ + if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr))) + out_of_memory(cinfo, 3); /* request exceeds malloc's ability */ + + /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */ + odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE); + if (odd_bytes > 0) + sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes; + + /* Always make a new pool */ + if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS) + ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */ + + hdr_ptr = (large_pool_ptr) jpeg_get_large(cinfo, sizeofobject + + SIZEOF(large_pool_hdr)); + if (hdr_ptr == NULL) + out_of_memory(cinfo, 4); /* jpeg_get_large failed */ + mem->total_space_allocated += sizeofobject + SIZEOF(large_pool_hdr); + + /* Success, initialize the new pool header and add to list */ + hdr_ptr->hdr.next = mem->large_list[pool_id]; + /* We maintain space counts in each pool header for statistical purposes, + * even though they are not needed for allocation. + */ + hdr_ptr->hdr.bytes_used = sizeofobject; + hdr_ptr->hdr.bytes_left = 0; + mem->large_list[pool_id] = hdr_ptr; + + return (void FAR *) (hdr_ptr + 1); /* point to first data byte in pool */ +} + + +/* + * Creation of 2-D sample arrays. + * The pointers are in near heap, the samples themselves in FAR heap. + * + * To minimize allocation overhead and to allow I/O of large contiguous + * blocks, we allocate the sample rows in groups of as many rows as possible + * without exceeding MAX_ALLOC_CHUNK total bytes per allocation request. + * NB: the virtual array control routines, later in this file, know about + * this chunking of rows. The rowsperchunk value is left in the mem manager + * object so that it can be saved away if this sarray is the workspace for + * a virtual array. + */ + +METHODDEF(JSAMPARRAY) +alloc_sarray (j_common_ptr cinfo, int pool_id, + JDIMENSION samplesperrow, JDIMENSION numrows) +/* Allocate a 2-D sample array */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + JSAMPARRAY result; + JSAMPROW workspace; + JDIMENSION rowsperchunk, currow, i; + long ltemp; + + /* Calculate max # of rows allowed in one allocation chunk */ + ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) / + ((long) samplesperrow * SIZEOF(JSAMPLE)); + if (ltemp <= 0) + ERREXIT(cinfo, JERR_WIDTH_OVERFLOW); + if (ltemp < (long) numrows) + rowsperchunk = (JDIMENSION) ltemp; + else + rowsperchunk = numrows; + mem->last_rowsperchunk = rowsperchunk; + + /* Get space for row pointers (small object) */ + result = (JSAMPARRAY) alloc_small(cinfo, pool_id, + (size_t) (numrows * SIZEOF(JSAMPROW))); + + /* Get the rows themselves (large objects) */ + currow = 0; + while (currow < numrows) { + rowsperchunk = MIN(rowsperchunk, numrows - currow); + workspace = (JSAMPROW) alloc_large(cinfo, pool_id, + (size_t) ((size_t) rowsperchunk * (size_t) samplesperrow + * SIZEOF(JSAMPLE))); + for (i = rowsperchunk; i > 0; i--) { + result[currow++] = workspace; + workspace += samplesperrow; + } + } + + return result; +} + + +/* + * Creation of 2-D coefficient-block arrays. + * This is essentially the same as the code for sample arrays, above. + */ + +METHODDEF(JBLOCKARRAY) +alloc_barray (j_common_ptr cinfo, int pool_id, + JDIMENSION blocksperrow, JDIMENSION numrows) +/* Allocate a 2-D coefficient-block array */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + JBLOCKARRAY result; + JBLOCKROW workspace; + JDIMENSION rowsperchunk, currow, i; + long ltemp; + + /* Calculate max # of rows allowed in one allocation chunk */ + ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) / + ((long) blocksperrow * SIZEOF(JBLOCK)); + if (ltemp <= 0) + ERREXIT(cinfo, JERR_WIDTH_OVERFLOW); + if (ltemp < (long) numrows) + rowsperchunk = (JDIMENSION) ltemp; + else + rowsperchunk = numrows; + mem->last_rowsperchunk = rowsperchunk; + + /* Get space for row pointers (small object) */ + result = (JBLOCKARRAY) alloc_small(cinfo, pool_id, + (size_t) (numrows * SIZEOF(JBLOCKROW))); + + /* Get the rows themselves (large objects) */ + currow = 0; + while (currow < numrows) { + rowsperchunk = MIN(rowsperchunk, numrows - currow); + workspace = (JBLOCKROW) alloc_large(cinfo, pool_id, + (size_t) ((size_t) rowsperchunk * (size_t) blocksperrow + * SIZEOF(JBLOCK))); + for (i = rowsperchunk; i > 0; i--) { + result[currow++] = workspace; + workspace += blocksperrow; + } + } + + return result; +} + + +#ifdef NEED_DARRAY + +/* + * Creation of 2-D difference arrays. + * This is essentially the same as the code for sample arrays, above. + */ + +METHODDEF(JDIFFARRAY) +alloc_darray (j_common_ptr cinfo, int pool_id, + JDIMENSION diffsperrow, JDIMENSION numrows) +/* Allocate a 2-D difference array */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + JDIFFARRAY result; + JDIFFROW workspace; + JDIMENSION rowsperchunk, currow, i; + long ltemp; + + /* Calculate max # of rows allowed in one allocation chunk */ + ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) / + ((long) diffsperrow * SIZEOF(JDIFF)); + if (ltemp <= 0) + ERREXIT(cinfo, JERR_WIDTH_OVERFLOW); + if (ltemp < (long) numrows) + rowsperchunk = (JDIMENSION) ltemp; + else + rowsperchunk = numrows; + mem->last_rowsperchunk = rowsperchunk; + + /* Get space for row pointers (small object) */ + result = (JDIFFARRAY) alloc_small(cinfo, pool_id, + (size_t) (numrows * SIZEOF(JDIFFROW))); + + /* Get the rows themselves (large objects) */ + currow = 0; + while (currow < numrows) { + rowsperchunk = MIN(rowsperchunk, numrows - currow); + workspace = (JDIFFROW) alloc_large(cinfo, pool_id, + (size_t) ((size_t) rowsperchunk * (size_t) diffsperrow + * SIZEOF(JDIFF))); + for (i = rowsperchunk; i > 0; i--) { + result[currow++] = workspace; + workspace += diffsperrow; + } + } + + return result; +} + +#endif + + +/* + * About virtual array management: + * + * The above "normal" array routines are only used to allocate strip buffers + * (as wide as the image, but just a few rows high). Full-image-sized buffers + * are handled as "virtual" arrays. The array is still accessed a strip at a + * time, but the memory manager must save the whole array for repeated + * accesses. The intended implementation is that there is a strip buffer in + * memory (as high as is possible given the desired memory limit), plus a + * backing file that holds the rest of the array. + * + * The request_virt_array routines are told the total size of the image and + * the maximum number of rows that will be accessed at once. The in-memory + * buffer must be at least as large as the maxaccess value. + * + * The request routines create control blocks but not the in-memory buffers. + * That is postponed until realize_virt_arrays is called. At that time the + * total amount of space needed is known (approximately, anyway), so free + * memory can be divided up fairly. + * + * The access_virt_array routines are responsible for making a specific strip + * area accessible (after reading or writing the backing file, if necessary). + * Note that the access routines are told whether the caller intends to modify + * the accessed strip; during a read-only pass this saves having to rewrite + * data to disk. The access routines are also responsible for pre-zeroing + * any newly accessed rows, if pre-zeroing was requested. + * + * In current usage, the access requests are usually for nonoverlapping + * strips; that is, successive access start_row numbers differ by exactly + * num_rows = maxaccess. This means we can get good performance with simple + * buffer dump/reload logic, by making the in-memory buffer be a multiple + * of the access height; then there will never be accesses across bufferload + * boundaries. The code will still work with overlapping access requests, + * but it doesn't handle bufferload overlaps very efficiently. + */ + + +METHODDEF(jvirt_sarray_ptr) +request_virt_sarray (j_common_ptr cinfo, int pool_id, boolean pre_zero, + JDIMENSION samplesperrow, JDIMENSION numrows, + JDIMENSION maxaccess) +/* Request a virtual 2-D sample array */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + jvirt_sarray_ptr result; + + /* Only IMAGE-lifetime virtual arrays are currently supported */ + if (pool_id != JPOOL_IMAGE) + ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */ + + /* get control block */ + result = (jvirt_sarray_ptr) alloc_small(cinfo, pool_id, + SIZEOF(struct jvirt_sarray_control)); + + result->mem_buffer = NULL; /* marks array not yet realized */ + result->rows_in_array = numrows; + result->samplesperrow = samplesperrow; + result->maxaccess = maxaccess; + result->pre_zero = pre_zero; + result->b_s_open = FALSE; /* no associated backing-store object */ + result->next = mem->virt_sarray_list; /* add to list of virtual arrays */ + mem->virt_sarray_list = result; + + return result; +} + + +METHODDEF(jvirt_barray_ptr) +request_virt_barray (j_common_ptr cinfo, int pool_id, boolean pre_zero, + JDIMENSION blocksperrow, JDIMENSION numrows, + JDIMENSION maxaccess) +/* Request a virtual 2-D coefficient-block array */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + jvirt_barray_ptr result; + + /* Only IMAGE-lifetime virtual arrays are currently supported */ + if (pool_id != JPOOL_IMAGE) + ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */ + + /* get control block */ + result = (jvirt_barray_ptr) alloc_small(cinfo, pool_id, + SIZEOF(struct jvirt_barray_control)); + + result->mem_buffer = NULL; /* marks array not yet realized */ + result->rows_in_array = numrows; + result->blocksperrow = blocksperrow; + result->maxaccess = maxaccess; + result->pre_zero = pre_zero; + result->b_s_open = FALSE; /* no associated backing-store object */ + result->next = mem->virt_barray_list; /* add to list of virtual arrays */ + mem->virt_barray_list = result; + + return result; +} + + +METHODDEF(void) +realize_virt_arrays (j_common_ptr cinfo) +/* Allocate the in-memory buffers for any unrealized virtual arrays */ +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + long space_per_minheight, maximum_space, avail_mem; + long minheights, max_minheights; + jvirt_sarray_ptr sptr; + jvirt_barray_ptr bptr; + + /* Compute the minimum space needed (maxaccess rows in each buffer) + * and the maximum space needed (full image height in each buffer). + * These may be of use to the system-dependent jpeg_mem_available routine. + */ + space_per_minheight = 0; + maximum_space = 0; + for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) { + if (sptr->mem_buffer == NULL) { /* if not realized yet */ + space_per_minheight += (long) sptr->maxaccess * + (long) sptr->samplesperrow * SIZEOF(JSAMPLE); + maximum_space += (long) sptr->rows_in_array * + (long) sptr->samplesperrow * SIZEOF(JSAMPLE); + } + } + for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) { + if (bptr->mem_buffer == NULL) { /* if not realized yet */ + space_per_minheight += (long) bptr->maxaccess * + (long) bptr->blocksperrow * SIZEOF(JBLOCK); + maximum_space += (long) bptr->rows_in_array * + (long) bptr->blocksperrow * SIZEOF(JBLOCK); + } + } + + if (space_per_minheight <= 0) + return; /* no unrealized arrays, no work */ + + /* Determine amount of memory to actually use; this is system-dependent. */ + avail_mem = jpeg_mem_available(cinfo, space_per_minheight, maximum_space, + mem->total_space_allocated); + + /* If the maximum space needed is available, make all the buffers full + * height; otherwise parcel it out with the same number of minheights + * in each buffer. + */ + if (avail_mem >= maximum_space) + max_minheights = 1000000000L; + else { + max_minheights = avail_mem / space_per_minheight; + /* If there doesn't seem to be enough space, try to get the minimum + * anyway. This allows a "stub" implementation of jpeg_mem_available(). + */ + if (max_minheights <= 0) + max_minheights = 1; + } + + /* Allocate the in-memory buffers and initialize backing store as needed. */ + + for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) { + if (sptr->mem_buffer == NULL) { /* if not realized yet */ + minheights = ((long) sptr->rows_in_array - 1L) / sptr->maxaccess + 1L; + if (minheights <= max_minheights) { + /* This buffer fits in memory */ + sptr->rows_in_mem = sptr->rows_in_array; + } else { + /* It doesn't fit in memory, create backing store. */ + sptr->rows_in_mem = (JDIMENSION) (max_minheights * sptr->maxaccess); + jpeg_open_backing_store(cinfo, & sptr->b_s_info, + (long) sptr->rows_in_array * + (long) sptr->samplesperrow * + (long) SIZEOF(JSAMPLE)); + sptr->b_s_open = TRUE; + } + sptr->mem_buffer = alloc_sarray(cinfo, JPOOL_IMAGE, + sptr->samplesperrow, sptr->rows_in_mem); + sptr->rowsperchunk = mem->last_rowsperchunk; + sptr->cur_start_row = 0; + sptr->first_undef_row = 0; + sptr->dirty = FALSE; + } + } + + for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) { + if (bptr->mem_buffer == NULL) { /* if not realized yet */ + minheights = ((long) bptr->rows_in_array - 1L) / bptr->maxaccess + 1L; + if (minheights <= max_minheights) { + /* This buffer fits in memory */ + bptr->rows_in_mem = bptr->rows_in_array; + } else { + /* It doesn't fit in memory, create backing store. */ + bptr->rows_in_mem = (JDIMENSION) (max_minheights * bptr->maxaccess); + jpeg_open_backing_store(cinfo, & bptr->b_s_info, + (long) bptr->rows_in_array * + (long) bptr->blocksperrow * + (long) SIZEOF(JBLOCK)); + bptr->b_s_open = TRUE; + } + bptr->mem_buffer = alloc_barray(cinfo, JPOOL_IMAGE, + bptr->blocksperrow, bptr->rows_in_mem); + bptr->rowsperchunk = mem->last_rowsperchunk; + bptr->cur_start_row = 0; + bptr->first_undef_row = 0; + bptr->dirty = FALSE; + } + } +} + + +LOCAL(void) +do_sarray_io (j_common_ptr cinfo, jvirt_sarray_ptr ptr, boolean writing) +/* Do backing store read or write of a virtual sample array */ +{ + long bytesperrow, file_offset, byte_count, rows, thisrow, i; + + bytesperrow = (long) ptr->samplesperrow * SIZEOF(JSAMPLE); + file_offset = ptr->cur_start_row * bytesperrow; + /* Loop to read or write each allocation chunk in mem_buffer */ + for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) { + /* One chunk, but check for short chunk at end of buffer */ + rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i); + /* Transfer no more than is currently defined */ + thisrow = (long) ptr->cur_start_row + i; + rows = MIN(rows, (long) ptr->first_undef_row - thisrow); + /* Transfer no more than fits in file */ + rows = MIN(rows, (long) ptr->rows_in_array - thisrow); + if (rows <= 0) /* this chunk might be past end of file! */ + break; + byte_count = rows * bytesperrow; + if (writing) + (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info, + (void FAR *) ptr->mem_buffer[i], + file_offset, byte_count); + else + (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info, + (void FAR *) ptr->mem_buffer[i], + file_offset, byte_count); + file_offset += byte_count; + } +} + + +LOCAL(void) +do_barray_io (j_common_ptr cinfo, jvirt_barray_ptr ptr, boolean writing) +/* Do backing store read or write of a virtual coefficient-block array */ +{ + long bytesperrow, file_offset, byte_count, rows, thisrow, i; + + bytesperrow = (long) ptr->blocksperrow * SIZEOF(JBLOCK); + file_offset = ptr->cur_start_row * bytesperrow; + /* Loop to read or write each allocation chunk in mem_buffer */ + for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) { + /* One chunk, but check for short chunk at end of buffer */ + rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i); + /* Transfer no more than is currently defined */ + thisrow = (long) ptr->cur_start_row + i; + rows = MIN(rows, (long) ptr->first_undef_row - thisrow); + /* Transfer no more than fits in file */ + rows = MIN(rows, (long) ptr->rows_in_array - thisrow); + if (rows <= 0) /* this chunk might be past end of file! */ + break; + byte_count = rows * bytesperrow; + if (writing) + (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info, + (void FAR *) ptr->mem_buffer[i], + file_offset, byte_count); + else + (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info, + (void FAR *) ptr->mem_buffer[i], + file_offset, byte_count); + file_offset += byte_count; + } +} + + +METHODDEF(JSAMPARRAY) +access_virt_sarray (j_common_ptr cinfo, jvirt_sarray_ptr ptr, + JDIMENSION start_row, JDIMENSION num_rows, + boolean writable) +/* Access the part of a virtual sample array starting at start_row */ +/* and extending for num_rows rows. writable is true if */ +/* caller intends to modify the accessed area. */ +{ + JDIMENSION end_row = start_row + num_rows; + JDIMENSION undef_row; + + /* debugging check */ + if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess || + ptr->mem_buffer == NULL) + ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS); + + /* Make the desired part of the virtual array accessible */ + if (start_row < ptr->cur_start_row || + end_row > ptr->cur_start_row+ptr->rows_in_mem) { + if (! ptr->b_s_open) + ERREXIT(cinfo, JERR_VIRTUAL_BUG); + /* Flush old buffer contents if necessary */ + if (ptr->dirty) { + do_sarray_io(cinfo, ptr, TRUE); + ptr->dirty = FALSE; + } + /* Decide what part of virtual array to access. + * Algorithm: if target address > current window, assume forward scan, + * load starting at target address. If target address < current window, + * assume backward scan, load so that target area is top of window. + * Note that when switching from forward write to forward read, will have + * start_row = 0, so the limiting case applies and we load from 0 anyway. + */ + if (start_row > ptr->cur_start_row) { + ptr->cur_start_row = start_row; + } else { + /* use long arithmetic here to avoid overflow & unsigned problems */ + long ltemp; + + ltemp = (long) end_row - (long) ptr->rows_in_mem; + if (ltemp < 0) + ltemp = 0; /* don't fall off front end of file */ + ptr->cur_start_row = (JDIMENSION) ltemp; + } + /* Read in the selected part of the array. + * During the initial write pass, we will do no actual read + * because the selected part is all undefined. + */ + do_sarray_io(cinfo, ptr, FALSE); + } + /* Ensure the accessed part of the array is defined; prezero if needed. + * To improve locality of access, we only prezero the part of the array + * that the caller is about to access, not the entire in-memory array. + */ + if (ptr->first_undef_row < end_row) { + if (ptr->first_undef_row < start_row) { + if (writable) /* writer skipped over a section of array */ + ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS); + undef_row = start_row; /* but reader is allowed to read ahead */ + } else { + undef_row = ptr->first_undef_row; + } + if (writable) + ptr->first_undef_row = end_row; + if (ptr->pre_zero) { + size_t bytesperrow = (size_t) ptr->samplesperrow * SIZEOF(JSAMPLE); + undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */ + end_row -= ptr->cur_start_row; + while (undef_row < end_row) { + jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow); + undef_row++; + } + } else { + if (! writable) /* reader looking at undefined data */ + ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS); + } + } + /* Flag the buffer dirty if caller will write in it */ + if (writable) + ptr->dirty = TRUE; + /* Return address of proper part of the buffer */ + return ptr->mem_buffer + (start_row - ptr->cur_start_row); +} + + +METHODDEF(JBLOCKARRAY) +access_virt_barray (j_common_ptr cinfo, jvirt_barray_ptr ptr, + JDIMENSION start_row, JDIMENSION num_rows, + boolean writable) +/* Access the part of a virtual block array starting at start_row */ +/* and extending for num_rows rows. writable is true if */ +/* caller intends to modify the accessed area. */ +{ + JDIMENSION end_row = start_row + num_rows; + JDIMENSION undef_row; + + /* debugging check */ + if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess || + ptr->mem_buffer == NULL) + ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS); + + /* Make the desired part of the virtual array accessible */ + if (start_row < ptr->cur_start_row || + end_row > ptr->cur_start_row+ptr->rows_in_mem) { + if (! ptr->b_s_open) + ERREXIT(cinfo, JERR_VIRTUAL_BUG); + /* Flush old buffer contents if necessary */ + if (ptr->dirty) { + do_barray_io(cinfo, ptr, TRUE); + ptr->dirty = FALSE; + } + /* Decide what part of virtual array to access. + * Algorithm: if target address > current window, assume forward scan, + * load starting at target address. If target address < current window, + * assume backward scan, load so that target area is top of window. + * Note that when switching from forward write to forward read, will have + * start_row = 0, so the limiting case applies and we load from 0 anyway. + */ + if (start_row > ptr->cur_start_row) { + ptr->cur_start_row = start_row; + } else { + /* use long arithmetic here to avoid overflow & unsigned problems */ + long ltemp; + + ltemp = (long) end_row - (long) ptr->rows_in_mem; + if (ltemp < 0) + ltemp = 0; /* don't fall off front end of file */ + ptr->cur_start_row = (JDIMENSION) ltemp; + } + /* Read in the selected part of the array. + * During the initial write pass, we will do no actual read + * because the selected part is all undefined. + */ + do_barray_io(cinfo, ptr, FALSE); + } + /* Ensure the accessed part of the array is defined; prezero if needed. + * To improve locality of access, we only prezero the part of the array + * that the caller is about to access, not the entire in-memory array. + */ + if (ptr->first_undef_row < end_row) { + if (ptr->first_undef_row < start_row) { + if (writable) /* writer skipped over a section of array */ + ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS); + undef_row = start_row; /* but reader is allowed to read ahead */ + } else { + undef_row = ptr->first_undef_row; + } + if (writable) + ptr->first_undef_row = end_row; + if (ptr->pre_zero) { + size_t bytesperrow = (size_t) ptr->blocksperrow * SIZEOF(JBLOCK); + undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */ + end_row -= ptr->cur_start_row; + while (undef_row < end_row) { + jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow); + undef_row++; + } + } else { + if (! writable) /* reader looking at undefined data */ + ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS); + } + } + /* Flag the buffer dirty if caller will write in it */ + if (writable) + ptr->dirty = TRUE; + /* Return address of proper part of the buffer */ + return ptr->mem_buffer + (start_row - ptr->cur_start_row); +} + + +/* + * Release all objects belonging to a specified pool. + */ + +METHODDEF(void) +free_pool (j_common_ptr cinfo, int pool_id) +{ + my_mem_ptr mem = (my_mem_ptr) cinfo->mem; + small_pool_ptr shdr_ptr; + large_pool_ptr lhdr_ptr; + size_t space_freed; + + if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS) + ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */ + +#ifdef MEM_STATS + if (cinfo->err->trace_level > 1) + print_mem_stats(cinfo, pool_id); /* print pool's memory usage statistics */ +#endif + + /* If freeing IMAGE pool, close any virtual arrays first */ + if (pool_id == JPOOL_IMAGE) { + jvirt_sarray_ptr sptr; + jvirt_barray_ptr bptr; + + for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) { + if (sptr->b_s_open) { /* there may be no backing store */ + sptr->b_s_open = FALSE; /* prevent recursive close if error */ + (*sptr->b_s_info.close_backing_store) (cinfo, & sptr->b_s_info); + } + } + mem->virt_sarray_list = NULL; + for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) { + if (bptr->b_s_open) { /* there may be no backing store */ + bptr->b_s_open = FALSE; /* prevent recursive close if error */ + (*bptr->b_s_info.close_backing_store) (cinfo, & bptr->b_s_info); + } + } + mem->virt_barray_list = NULL; + } + + /* Release large objects */ + lhdr_ptr = mem->large_list[pool_id]; + mem->large_list[pool_id] = NULL; + + while (lhdr_ptr != NULL) { + large_pool_ptr next_lhdr_ptr = lhdr_ptr->hdr.next; + space_freed = lhdr_ptr->hdr.bytes_used + + lhdr_ptr->hdr.bytes_left + + SIZEOF(large_pool_hdr); + jpeg_free_large(cinfo, (void FAR *) lhdr_ptr, space_freed); + mem->total_space_allocated -= space_freed; + lhdr_ptr = next_lhdr_ptr; + } + + /* Release small objects */ + shdr_ptr = mem->small_list[pool_id]; + mem->small_list[pool_id] = NULL; + + while (shdr_ptr != NULL) { + small_pool_ptr next_shdr_ptr = shdr_ptr->hdr.next; + space_freed = shdr_ptr->hdr.bytes_used + + shdr_ptr->hdr.bytes_left + + SIZEOF(small_pool_hdr); + jpeg_free_small(cinfo, (void *) shdr_ptr, space_freed); + mem->total_space_allocated -= space_freed; + shdr_ptr = next_shdr_ptr; + } +} + + +/* + * Close up shop entirely. + * Note that this cannot be called unless cinfo->mem is non-NULL. + */ + +METHODDEF(void) +self_destruct (j_common_ptr cinfo) +{ + int pool; + + /* Close all backing store, release all memory. + * Releasing pools in reverse order might help avoid fragmentation + * with some (brain-damaged) malloc libraries. + */ + for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) { + free_pool(cinfo, pool); + } + + /* Release the memory manager control block too. */ + jpeg_free_small(cinfo, (void *) cinfo->mem, SIZEOF(my_memory_mgr)); + cinfo->mem = NULL; /* ensures I will be called only once */ + + jpeg_mem_term(cinfo); /* system-dependent cleanup */ +} + + +/* + * Memory manager initialization. + * When this is called, only the error manager pointer is valid in cinfo! + */ + +GLOBAL(void) +jinit_memory_mgr (j_common_ptr cinfo) +{ + my_mem_ptr mem; + long max_to_use; + int pool; + size_t test_mac; + + cinfo->mem = NULL; /* for safety if init fails */ + + /* Check for configuration errors. + * SIZEOF(ALIGN_TYPE) should be a power of 2; otherwise, it probably + * doesn't reflect any real hardware alignment requirement. + * The test is a little tricky: for X>0, X and X-1 have no one-bits + * in common if and only if X is a power of 2, ie has only one one-bit. + * Some compilers may give an "unreachable code" warning here; ignore it. + */ + if ((SIZEOF(ALIGN_TYPE) & (SIZEOF(ALIGN_TYPE)-1)) != 0) + ERREXIT(cinfo, JERR_BAD_ALIGN_TYPE); + /* MAX_ALLOC_CHUNK must be representable as type size_t, and must be + * a multiple of SIZEOF(ALIGN_TYPE). + * Again, an "unreachable code" warning may be ignored here. + * But a "constant too large" warning means you need to fix MAX_ALLOC_CHUNK. + */ + test_mac = (size_t) MAX_ALLOC_CHUNK; + if ((long) test_mac != MAX_ALLOC_CHUNK || + (MAX_ALLOC_CHUNK % SIZEOF(ALIGN_TYPE)) != 0) + ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK); + + max_to_use = jpeg_mem_init(cinfo); /* system-dependent initialization */ + + /* Attempt to allocate memory manager's control block */ + mem = (my_mem_ptr) jpeg_get_small(cinfo, SIZEOF(my_memory_mgr)); + + if (mem == NULL) { + jpeg_mem_term(cinfo); /* system-dependent cleanup */ + ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 0); + } + + /* OK, fill in the method pointers */ + mem->pub.alloc_small = alloc_small; + mem->pub.alloc_large = alloc_large; + mem->pub.alloc_sarray = alloc_sarray; + mem->pub.alloc_barray = alloc_barray; +#ifdef NEED_DARRAY + mem->pub.alloc_darray = alloc_darray; +#endif + mem->pub.request_virt_sarray = request_virt_sarray; + mem->pub.request_virt_barray = request_virt_barray; + mem->pub.realize_virt_arrays = realize_virt_arrays; + mem->pub.access_virt_sarray = access_virt_sarray; + mem->pub.access_virt_barray = access_virt_barray; + mem->pub.free_pool = free_pool; + mem->pub.self_destruct = self_destruct; + + /* Make MAX_ALLOC_CHUNK accessible to other modules */ + mem->pub.max_alloc_chunk = MAX_ALLOC_CHUNK; + + /* Initialize working state */ + mem->pub.max_memory_to_use = max_to_use; + + for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) { + mem->small_list[pool] = NULL; + mem->large_list[pool] = NULL; + } + mem->virt_sarray_list = NULL; + mem->virt_barray_list = NULL; + + mem->total_space_allocated = SIZEOF(my_memory_mgr); + + /* Declare ourselves open for business */ + cinfo->mem = & mem->pub; + + /* Check for an environment variable JPEGMEM; if found, override the + * default max_memory setting from jpeg_mem_init. Note that the + * surrounding application may again override this value. + * If your system doesn't support getenv(), define NO_GETENV to disable + * this feature. + */ +#ifndef NO_GETENV + { char * memenv; + + if ((memenv = getenv("JPEGMEM")) != NULL) { + char ch = 'x'; + + if (sscanf(memenv, "%ld%c", &max_to_use, &ch) > 0) { + if (ch == 'm' || ch == 'M') + max_to_use *= 1000L; + mem->pub.max_memory_to_use = max_to_use * 1000L; + } + } + } +#endif + +} diff --git a/src/gdcmjpeg/jmemnobs.c b/src/gdcmjpeg/jmemnobs.c new file mode 100644 index 00000000..6757d4b3 --- /dev/null +++ b/src/gdcmjpeg/jmemnobs.c @@ -0,0 +1,117 @@ +/* + * jmemnobs.c + * + * Copyright (C) 1992-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file provides a really simple implementation of the system- + * dependent portion of the JPEG memory manager. This implementation + * assumes that no backing-store files are needed: all required space + * can be obtained from malloc(). + * This is very portable in the sense that it'll compile on almost anything, + * but you'd better have lots of main memory (or virtual memory) if you want + * to process big images. + * Note that the max_memory_to_use option is ignored by this implementation. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" +#include "jmemsys.h" /* import the system-dependent declarations */ + +#ifndef HAVE_STDLIB_H /* should declare malloc(),free() */ +extern void * malloc JPP((size_t size)); +extern void free JPP((void *ptr)); +#endif + + +/* + * Memory allocation and freeing are controlled by the regular library + * routines malloc() and free(). + */ + +GLOBAL(void *) +jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject) +{ + (void)cinfo; + return (void *) malloc(sizeofobject); +} + +GLOBAL(void) +jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject) +{ + (void)cinfo;(void)sizeofobject; + free(object); +} + + +/* + * "Large" objects are treated the same as "small" ones. + * NB: although we include FAR keywords in the routine declarations, + * this file won't actually work in 80x86 small/medium model; at least, + * you probably won't be able to process useful-size images in only 64KB. + */ + +GLOBAL(void FAR *) +jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject) +{ + (void)cinfo; + return (void FAR *) malloc(sizeofobject); +} + +GLOBAL(void) +jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject) +{ + (void)cinfo;(void)sizeofobject; + free(object); +} + + +/* + * This routine computes the total memory space available for allocation. + * Here we always say, "we got all you want bud!" + */ + +GLOBAL(long) +jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed, + long max_bytes_needed, long already_allocated) +{ + (void)cinfo;(void)min_bytes_needed;(void)already_allocated; + return max_bytes_needed; +} + + +/* + * Backing store (temporary file) management. + * Since jpeg_mem_available always promised the moon, + * this should never be called and we can just error out. + */ + +GLOBAL(void) +jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info, + long total_bytes_needed) +{ + (void)info;(void)total_bytes_needed; + ERREXIT(cinfo, JERR_NO_BACKING_STORE); +} + + +/* + * These routines take care of any system-dependent initialization and + * cleanup required. Here, there isn't any. + */ + +GLOBAL(long) +jpeg_mem_init (j_common_ptr cinfo) +{ + (void)cinfo; + return 0; /* just set max_memory_to_use to 0 */ +} + +GLOBAL(void) +jpeg_mem_term (j_common_ptr cinfo) +{ + (void)cinfo; + /* no work */ +} diff --git a/src/gdcmjpeg/jmemsys.h b/src/gdcmjpeg/jmemsys.h new file mode 100644 index 00000000..2e8ee7ee --- /dev/null +++ b/src/gdcmjpeg/jmemsys.h @@ -0,0 +1,198 @@ +/* + * jmemsys.h + * + * Copyright (C) 1992-1997, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This include file defines the interface between the system-independent + * and system-dependent portions of the JPEG memory manager. No other + * modules need include it. (The system-independent portion is jmemmgr.c; + * there are several different versions of the system-dependent portion.) + * + * This file works as-is for the system-dependent memory managers supplied + * in the IJG distribution. You may need to modify it if you write a + * custom memory manager. If system-dependent changes are needed in + * this file, the best method is to #ifdef them based on a configuration + * symbol supplied in jconfig.h, as we have done with USE_MSDOS_MEMMGR + * and USE_MAC_MEMMGR. + */ + + +/* Short forms of external names for systems with brain-damaged linkers. */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jpeg_get_small jGetSmall +#define jpeg_free_small jFreeSmall +#define jpeg_get_large jGetLarge +#define jpeg_free_large jFreeLarge +#define jpeg_mem_available jMemAvail +#define jpeg_open_backing_store jOpenBackStore +#define jpeg_mem_init jMemInit +#define jpeg_mem_term jMemTerm +#endif /* NEED_SHORT_EXTERNAL_NAMES */ + + +/* + * These two functions are used to allocate and release small chunks of + * memory. (Typically the total amount requested through jpeg_get_small is + * no more than 20K or so; this will be requested in chunks of a few K each.) + * Behavior should be the same as for the standard library functions malloc + * and free; in particular, jpeg_get_small must return NULL on failure. + * On most systems, these ARE malloc and free. jpeg_free_small is passed the + * size of the object being freed, just in case it's needed. + * On an 80x86 machine using small-data memory model, these manage near heap. + */ + +EXTERN(void *) jpeg_get_small JPP((j_common_ptr cinfo, size_t sizeofobject)); +EXTERN(void) jpeg_free_small JPP((j_common_ptr cinfo, void * object, + size_t sizeofobject)); + +/* + * These two functions are used to allocate and release large chunks of + * memory (up to the total free space designated by jpeg_mem_available). + * The interface is the same as above, except that on an 80x86 machine, + * far pointers are used. On most other machines these are identical to + * the jpeg_get/free_small routines; but we keep them separate anyway, + * in case a different allocation strategy is desirable for large chunks. + */ + +EXTERN(void FAR *) jpeg_get_large JPP((j_common_ptr cinfo, + size_t sizeofobject)); +EXTERN(void) jpeg_free_large JPP((j_common_ptr cinfo, void FAR * object, + size_t sizeofobject)); + +/* + * The macro MAX_ALLOC_CHUNK designates the maximum number of bytes that may + * be requested in a single call to jpeg_get_large (and jpeg_get_small for that + * matter, but that case should never come into play). This macro is needed + * to model the 64Kb-segment-size limit of far addressing on 80x86 machines. + * On those machines, we expect that jconfig.h will provide a proper value. + * On machines with 32-bit flat address spaces, any large constant may be used. + * + * NB: jmemmgr.c expects that MAX_ALLOC_CHUNK will be representable as type + * size_t and will be a multiple of sizeof(align_type). + */ + +#ifndef MAX_ALLOC_CHUNK /* may be overridden in jconfig.h */ +#define MAX_ALLOC_CHUNK 1000000000L +#endif + +/* + * This routine computes the total space still available for allocation by + * jpeg_get_large. If more space than this is needed, backing store will be + * used. NOTE: any memory already allocated must not be counted. + * + * There is a minimum space requirement, corresponding to the minimum + * feasible buffer sizes; jmemmgr.c will request that much space even if + * jpeg_mem_available returns zero. The maximum space needed, enough to hold + * all working storage in memory, is also passed in case it is useful. + * Finally, the total space already allocated is passed. If no better + * method is available, cinfo->mem->max_memory_to_use - already_allocated + * is often a suitable calculation. + * + * It is OK for jpeg_mem_available to underestimate the space available + * (that'll just lead to more backing-store access than is really necessary). + * However, an overestimate will lead to failure. Hence it's wise to subtract + * a slop factor from the true available space. 5% should be enough. + * + * On machines with lots of virtual memory, any large constant may be returned. + * Conversely, zero may be returned to always use the minimum amount of memory. + */ + +EXTERN(long) jpeg_mem_available JPP((j_common_ptr cinfo, + long min_bytes_needed, + long max_bytes_needed, + long already_allocated)); + + +/* + * This structure holds whatever state is needed to access a single + * backing-store object. The read/write/close method pointers are called + * by jmemmgr.c to manipulate the backing-store object; all other fields + * are private to the system-dependent backing store routines. + */ + +#define TEMP_NAME_LENGTH 64 /* max length of a temporary file's name */ + + +#ifdef USE_MSDOS_MEMMGR /* DOS-specific junk */ + +typedef unsigned short XMSH; /* type of extended-memory handles */ +typedef unsigned short EMSH; /* type of expanded-memory handles */ + +typedef union { + short file_handle; /* DOS file handle if it's a temp file */ + XMSH xms_handle; /* handle if it's a chunk of XMS */ + EMSH ems_handle; /* handle if it's a chunk of EMS */ +} handle_union; + +#endif /* USE_MSDOS_MEMMGR */ + +#ifdef USE_MAC_MEMMGR /* Mac-specific junk */ +#include +#endif /* USE_MAC_MEMMGR */ + + +typedef struct backing_store_struct * backing_store_ptr; + +typedef struct backing_store_struct { + /* Methods for reading/writing/closing this backing-store object */ + JMETHOD(void, read_backing_store, (j_common_ptr cinfo, + backing_store_ptr info, + void FAR * buffer_address, + long file_offset, long byte_count)); + JMETHOD(void, write_backing_store, (j_common_ptr cinfo, + backing_store_ptr info, + void FAR * buffer_address, + long file_offset, long byte_count)); + JMETHOD(void, close_backing_store, (j_common_ptr cinfo, + backing_store_ptr info)); + + /* Private fields for system-dependent backing-store management */ +#ifdef USE_MSDOS_MEMMGR + /* For the MS-DOS manager (jmemdos.c), we need: */ + handle_union handle; /* reference to backing-store storage object */ + char temp_name[TEMP_NAME_LENGTH]; /* name if it's a file */ +#else +#ifdef USE_MAC_MEMMGR + /* For the Mac manager (jmemmac.c), we need: */ + short temp_file; /* file reference number to temp file */ + FSSpec tempSpec; /* the FSSpec for the temp file */ + char temp_name[TEMP_NAME_LENGTH]; /* name if it's a file */ +#else + /* For a typical implementation with temp files, we need: */ + FILE * temp_file; /* stdio reference to temp file */ + char temp_name[TEMP_NAME_LENGTH]; /* name of temp file */ +#endif +#endif +} backing_store_info; + + +/* + * Initial opening of a backing-store object. This must fill in the + * read/write/close pointers in the object. The read/write routines + * may take an error exit if the specified maximum file size is exceeded. + * (If jpeg_mem_available always returns a large value, this routine can + * just take an error exit.) + */ + +EXTERN(void) jpeg_open_backing_store JPP((j_common_ptr cinfo, + backing_store_ptr info, + long total_bytes_needed)); + + +/* + * These routines take care of any system-dependent initialization and + * cleanup required. jpeg_mem_init will be called before anything is + * allocated (and, therefore, nothing in cinfo is of use except the error + * manager pointer). It should return a suitable default value for + * max_memory_to_use; this may subsequently be overridden by the surrounding + * application. (Note that max_memory_to_use is only important if + * jpeg_mem_available chooses to consult it ... no one else will.) + * jpeg_mem_term may assume that all requested memory has been freed and that + * all opened backing-store objects have been closed. + */ + +EXTERN(long) jpeg_mem_init JPP((j_common_ptr cinfo)); +EXTERN(void) jpeg_mem_term JPP((j_common_ptr cinfo)); diff --git a/src/gdcmjpeg/jmorecfg.h.in b/src/gdcmjpeg/jmorecfg.h.in new file mode 100644 index 00000000..621dc0e3 --- /dev/null +++ b/src/gdcmjpeg/jmorecfg.h.in @@ -0,0 +1,435 @@ +/* + * jmorecfg.h + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains additional configuration options that customize the + * JPEG software for special applications or support machine-dependent + * optimizations. Most users will not need to touch this file. + */ + +/* + * Define BITS_IN_JSAMPLE as either + * 8 for 8-bit sample values (the usual setting) + * 12 for 12-bit sample values + * Only 8 and 12 are legal data precisions for lossy JPEG according to the + * JPEG standard, and the IJG code does not support anything else! + * We do not support run-time selection of data precision, sorry. + */ + +/*#define BITS_IN_JSAMPLE 8*//* use 8 or 12 (or 16 only for lossless) */ +#define BITS_IN_JSAMPLE @CMAKE_BITS_IN_JSAMPLE@ + +/* + * Maximum number of components (color channels) allowed in JPEG image. + * To meet the letter of the JPEG spec, set this to 255. However, darn + * few applications need more than 4 channels (maybe 5 for CMYK + alpha + * mask). We recommend 10 as a reasonable compromise; use 4 if you are + * really short on memory. (Each allowed component costs a hundred or so + * bytes of storage, whether actually used in an image or not.) + */ + +#define MAX_COMPONENTS 10 /* maximum number of image components */ + + +/* + * Basic data types. + * You may need to change these if you have a machine with unusual data + * type sizes; for example, "char" not 8 bits, "short" not 16 bits, + * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits, + * but it had better be at least 16. + */ + +/* Representation of a single sample (pixel element value). + * We frequently allocate large arrays of these, so it's important to keep + * them small. But if you have memory to burn and access to char or short + * arrays is very slow on your hardware, you might want to change these. + */ + +#if BITS_IN_JSAMPLE == 8 +/* JSAMPLE should be the smallest type that will hold the values 0..255. + * You can use a signed char by having GETJSAMPLE mask it with 0xFF. + */ + +#ifdef HAVE_UNSIGNED_CHAR + +typedef unsigned char JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#else /* not HAVE_UNSIGNED_CHAR */ + +typedef char JSAMPLE; +#ifdef CHAR_IS_UNSIGNED +#define GETJSAMPLE(value) ((int) (value)) +#else +#define GETJSAMPLE(value) ((int) (value) & 0xFF) +#endif /* CHAR_IS_UNSIGNED */ + +#endif /* HAVE_UNSIGNED_CHAR */ + +#define MAXJSAMPLE 255 +#define CENTERJSAMPLE 128 + +#endif /* BITS_IN_JSAMPLE == 8 */ + + +#if BITS_IN_JSAMPLE == 12 +/* JSAMPLE should be the smallest type that will hold the values 0..4095. + * On nearly all machines "short" will do nicely. + */ + +typedef short JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#define MAXJSAMPLE 4095 +#define CENTERJSAMPLE 2048 + +#endif /* BITS_IN_JSAMPLE == 12 */ + + +#if BITS_IN_JSAMPLE == 16 +/* JSAMPLE should be the smallest type that will hold the values 0..65535. + * You can use a signed short by having GETJSAMPLE mask it with 0xFFFF. + */ + +#ifdef HAVE_UNSIGNED_SHORT + +typedef unsigned short JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#else /* not HAVE_UNSIGNED_SHORT */ + +typedef short JSAMPLE; +#ifdef SHORT_IS_UNSIGNED +#define GETJSAMPLE(value) ((int) (value)) +#else +#define GETJSAMPLE(value) ((int) (value) & 0xFFFF) +#endif /* SHORT_IS_UNSIGNED */ + +#endif /* HAVE_UNSIGNED_SHORT */ + +#define MAXJSAMPLE 65535 +#define CENTERJSAMPLE 32768 + +#endif /* BITS_IN_JSAMPLE == 16 */ + + +/* Representation of a DCT frequency coefficient. + * This should be a signed value of at least 16 bits; "short" is usually OK. + * Again, we allocate large arrays of these, but you can change to int + * if you have memory to burn and "short" is really slow. + */ + +typedef short JCOEF; + + +/* Representation of a spatial difference value. + * This should be a signed value of at least 16 bits; int is usually OK. + */ + +typedef int JDIFF; + + +/* Compressed datastreams are represented as arrays of JOCTET. + * These must be EXACTLY 8 bits wide, at least once they are written to + * external storage. Note that when using the stdio data source/destination + * managers, this is also the data type passed to fread/fwrite. + */ + +#ifdef HAVE_UNSIGNED_CHAR + +typedef unsigned char JOCTET; +#define GETJOCTET(value) (value) + +#else /* not HAVE_UNSIGNED_CHAR */ + +typedef char JOCTET; +#ifdef CHAR_IS_UNSIGNED +#define GETJOCTET(value) (value) +#else +#define GETJOCTET(value) ((value) & 0xFF) +#endif /* CHAR_IS_UNSIGNED */ + +#endif /* HAVE_UNSIGNED_CHAR */ + + +/* These typedefs are used for various table entries and so forth. + * They must be at least as wide as specified; but making them too big + * won't cost a huge amount of memory, so we don't provide special + * extraction code like we did for JSAMPLE. (In other words, these + * typedefs live at a different point on the speed/space tradeoff curve.) + */ + +/* UINT8 must hold at least the values 0..255. */ + +#ifdef HAVE_UNSIGNED_CHAR +typedef unsigned char UINT8; +#else /* not HAVE_UNSIGNED_CHAR */ +#ifdef CHAR_IS_UNSIGNED +typedef char UINT8; +#else /* not CHAR_IS_UNSIGNED */ +typedef short UINT8; +#endif /* CHAR_IS_UNSIGNED */ +#endif /* HAVE_UNSIGNED_CHAR */ + +/* UINT16 must hold at least the values 0..65535. */ + +#ifdef HAVE_UNSIGNED_SHORT +typedef unsigned short UINT16; +#else /* not HAVE_UNSIGNED_SHORT */ +typedef unsigned int UINT16; +#endif /* HAVE_UNSIGNED_SHORT */ + +/* INT16 must hold at least the values -32768..32767. */ + +#ifndef XMD_H /* X11/xmd.h correctly defines INT16 */ +typedef short INT16; +#endif + +/* INT32 must hold at least signed 32-bit values. */ +/* X11/xmd.h and basetsd.h correctly defines INT32 */ + +#if !defined(XMD_H) && !defined(_BASETSD_H_) +typedef int INT32; +#endif + +/* Datatype used for image dimensions. The JPEG standard only supports + * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore + * "unsigned int" is sufficient on all machines. However, if you need to + * handle larger images and you don't mind deviating from the spec, you + * can change this datatype. + */ + +typedef unsigned int JDIMENSION; + +#define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */ + + +/* These macros are used in all function definitions and extern declarations. + * You could modify them if you need to change function linkage conventions; + * in particular, you'll need to do that to make the library a Windows DLL. + * Another application is to make all functions global for use with debuggers + * or code profilers that require it. + */ + +/* a function called through method pointers: */ +#define METHODDEF(type) static type +/* a function used only in its module: */ +#define LOCAL(type) static type +/* a function referenced thru EXTERNs: */ +#if defined( _WIN32 ) && defined (JPEGDLL) +#define GLOBAL(type) __declspec(dllexport) type +#else +#define GLOBAL(type) type +#endif + +/* a reference to a GLOBAL function: */ +#if defined(_WIN32) && !defined(JPEGSTATIC) +#ifdef JPEGDLL +/* Win32, building a dll */ +#define EXTERN(type) __declspec(dllexport) type +#else +/* Win32, not building a dll but using the dll */ +#define EXTERN(type) __declspec(dllimport) type +#endif +#else +/* not a Win32 system or building a static Win32 lib */ +#define EXTERN(type) extern type +#endif + + +/* This macro is used to declare a "method", that is, a function pointer. + * We want to supply prototype parameters if the compiler can cope. + * Note that the arglist parameter must be parenthesized! + * Again, you can customize this if you need special linkage keywords. + */ + +#ifdef HAVE_PROTOTYPES +#define JMETHOD(type,methodname,arglist) type (*methodname) arglist +#else +#define JMETHOD(type,methodname,arglist) type (*methodname) () +#endif + + +/* Here is the pseudo-keyword for declaring pointers that must be "far" + * on 80x86 machines. Most of the specialized coding for 80x86 is handled + * by just saying "FAR *" where such a pointer is needed. In a few places + * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol. + */ + +#ifndef FAR +#ifdef NEED_FAR_POINTERS +#define FAR far +#else +#define FAR +#endif +#endif + + +/* + * On a few systems, type boolean and/or its values FALSE, TRUE may appear + * in standard header files. Or you may have conflicts with application- + * specific header files that you want to include together with these files. + * Defining HAVE_BOOLEAN before including jpeglib.h should make it work. + */ + +#ifndef HAVE_BOOLEAN +typedef int boolean; +#endif +#ifndef FALSE /* in case these macros already exist */ +#define FALSE 0 /* values of boolean */ +#endif +#ifndef TRUE +#define TRUE 1 +#endif + + +/* + * The remaining options affect code selection within the JPEG library, + * but they don't need to be visible to most applications using the library. + * To minimize application namespace pollution, the symbols won't be + * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined. + */ + +#ifdef JPEG_INTERNALS +#define JPEG_INTERNAL_OPTIONS +#endif + +#ifdef JPEG_INTERNAL_OPTIONS + + +/* + * These defines indicate whether to include various optional functions. + * Undefining some of these symbols will produce a smaller but less capable + * library. Note that you can leave certain source files out of the + * compilation/linking process if you've #undef'd the corresponding symbols. + * (You may HAVE to do that if your compiler doesn't like null source files.) + */ + +/* Arithmetic coding is unsupported for legal reasons. Complaints to IBM. */ + +/* Capability options common to encoder and decoder: */ + +#define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */ +#define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */ +#define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */ + +/* Encoder capability options: */ + +#undef C_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */ +#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ +#define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ +#define C_LOSSLESS_SUPPORTED /* Lossless JPEG? */ +#define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */ +/* Note: if you selected 12-bit data precision, it is dangerous to turn off + * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit + * precision, so jcshuff.c normally uses entropy optimization to compute + * usable tables for higher precision. If you don't want to do optimization, + * you'll have to supply different default Huffman tables. + * The exact same statements apply for progressive and lossless JPEG: + * the default tables don't work for progressive mode or lossless mode. + * (This may get fixed, however.) + */ +#define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */ + +/* Decoder capability options: */ + +#undef D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */ +#define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ +#define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ +#define D_LOSSLESS_SUPPORTED /* Lossless JPEG? */ +#define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ +#define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */ +#define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */ +#undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */ +#define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */ +#define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */ +#define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */ + +/* more capability options later, no doubt */ + + +/* + * Ordering of RGB data in scanlines passed to or from the application. + * If your application wants to deal with data in the order B,G,R, just + * change these macros. You can also deal with formats such as R,G,B,X + * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing + * the offsets will also change the order in which colormap data is organized. + * RESTRICTIONS: + * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats. + * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not + * useful if you are using JPEG color spaces other than YCbCr or grayscale. + * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE + * is not 3 (they don't understand about dummy color components!). So you + * can't use color quantization if you change that value. + */ + +#define RGB_RED 0 /* Offset of Red in an RGB scanline element */ +#define RGB_GREEN 1 /* Offset of Green */ +#define RGB_BLUE 2 /* Offset of Blue */ +#define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */ + + +/* Definitions for speed-related optimizations. */ + + +/* If your compiler supports inline functions, define INLINE + * as the inline keyword; otherwise define it as empty. + */ + +#ifndef INLINE +#ifdef __GNUC__ /* for instance, GNU C knows about inline */ +#define INLINE __inline__ +#endif +#ifndef INLINE +#define INLINE /* default is to define it as empty */ +#endif +#endif + + +/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying + * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER + * as short on such a machine. MULTIPLIER must be at least 16 bits wide. + */ + +#ifndef MULTIPLIER +#define MULTIPLIER int /* type for fastest integer multiply */ +#endif + + +/* FAST_FLOAT should be either float or double, whichever is done faster + * by your compiler. (Note that this type is only used in the floating point + * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.) + * Typically, float is faster in ANSI C compilers, while double is faster in + * pre-ANSI compilers (because they insist on converting to double anyway). + * The code below therefore chooses float if we have ANSI-style prototypes. + */ + +#ifndef FAST_FLOAT +#ifdef HAVE_PROTOTYPES +#define FAST_FLOAT float +#else +#define FAST_FLOAT double +#endif +#endif + +#if defined ( _MSC_VER ) +#pragma warning ( disable : 4100 ) +#pragma warning ( disable : 4115 ) +#pragma warning ( disable : 4127 ) +#pragma warning ( disable : 4244 ) +#pragma warning ( disable : 4251 ) +#pragma warning ( disable : 4267 ) +#pragma warning ( disable : 4305 ) +#pragma warning ( disable : 4309 ) +#pragma warning ( disable : 4706 ) +#pragma warning ( disable : 4786 ) +#pragma warning ( disable : 4057 ) +#pragma warning ( disable : 4189 ) +#pragma warning ( disable : 4505 ) +#endif + + +#endif /* JPEG_INTERNAL_OPTIONS */ diff --git a/src/gdcmjpeg/jpegint.h b/src/gdcmjpeg/jpegint.h new file mode 100644 index 00000000..684dada0 --- /dev/null +++ b/src/gdcmjpeg/jpegint.h @@ -0,0 +1,365 @@ +/* + * jpegint.h + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file provides common declarations for the various JPEG modules. + * These declarations are considered internal to the JPEG library; most + * applications using the library shouldn't need to include this file. + */ + + +/* Declarations for both compression & decompression */ + +typedef enum { /* Operating modes for buffer controllers */ + JBUF_PASS_THRU, /* Plain stripwise operation */ + /* Remaining modes require a full-image buffer to have been created */ + JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ + JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ + JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ +} J_BUF_MODE; + +/* Values of global_state field (jdapi.c has some dependencies on ordering!) */ +#define CSTATE_START 100 /* after create_compress */ +#define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ +#define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */ +#define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */ +#define DSTATE_START 200 /* after create_decompress */ +#define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */ +#define DSTATE_READY 202 /* found SOS, ready for start_decompress */ +#define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/ +#define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */ +#define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */ +#define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */ +#define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */ +#define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */ +#define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */ +#define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */ + + +/* Declarations for compression modules */ + +/* Master control module */ +struct jpeg_comp_master { + JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo)); + JMETHOD(void, pass_startup, (j_compress_ptr cinfo)); + JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); + + /* State variables made visible to other modules */ + boolean call_pass_startup; /* True if pass_startup must be called */ + boolean is_last_pass; /* True during last pass */ +}; + +/* Main buffer control (downsampled-data buffer) */ +struct jpeg_c_main_controller { + JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); + JMETHOD(void, process_data, (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, + JDIMENSION in_rows_avail)); +}; + +/* Compression preprocessing (downsampling input buffer control) */ +struct jpeg_c_prep_controller { + JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); + JMETHOD(void, pre_process_data, (j_compress_ptr cinfo, + JSAMPARRAY input_buf, + JDIMENSION *in_row_ctr, + JDIMENSION in_rows_avail, + JSAMPIMAGE output_buf, + JDIMENSION *out_row_group_ctr, + JDIMENSION out_row_groups_avail)); +}; + +/* Compression codec (compressor proper) */ +struct jpeg_c_codec { + JMETHOD(void, entropy_start_pass, (j_compress_ptr cinfo, + boolean gather_statistics)); + JMETHOD(void, entropy_finish_pass, (j_compress_ptr cinfo)); + JMETHOD(boolean, need_optimization_pass, (j_compress_ptr cinfo)); + JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); + JMETHOD(boolean, compress_data, (j_compress_ptr cinfo, + JSAMPIMAGE input_buf)); +}; + +/* Colorspace conversion */ +struct jpeg_color_converter { + JMETHOD(void, start_pass, (j_compress_ptr cinfo)); + JMETHOD(void, color_convert, (j_compress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPIMAGE output_buf, + JDIMENSION output_row, int num_rows)); +}; + +/* Downsampling */ +struct jpeg_downsampler { + JMETHOD(void, start_pass, (j_compress_ptr cinfo)); + JMETHOD(void, downsample, (j_compress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION in_row_index, + JSAMPIMAGE output_buf, + JDIMENSION out_row_group_index)); + + boolean need_context_rows; /* TRUE if need rows above & below */ +}; + +/* Marker writing */ +struct jpeg_marker_writer { + JMETHOD(void, write_file_header, (j_compress_ptr cinfo)); + JMETHOD(void, write_frame_header, (j_compress_ptr cinfo)); + JMETHOD(void, write_scan_header, (j_compress_ptr cinfo)); + JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo)); + JMETHOD(void, write_tables_only, (j_compress_ptr cinfo)); + /* These routines are exported to allow insertion of extra markers */ + /* Probably only COM and APPn markers should be written this way */ + JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker, + unsigned int datalen)); + JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val)); +}; + + +/* Declarations for decompression modules */ + +/* Master control module */ +struct jpeg_decomp_master { + JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo)); + + /* State variables made visible to other modules */ + boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */ +}; + +/* Input control module */ +struct jpeg_input_controller { + JMETHOD(int, consume_input, (j_decompress_ptr cinfo)); + JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo)); + JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo)); + + /* State variables made visible to other modules */ + boolean has_multiple_scans; /* True if file has multiple scans */ + boolean eoi_reached; /* True when EOI has been consumed */ +}; + +/* Main buffer control (downsampled-data buffer) */ +struct jpeg_d_main_controller { + JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); + JMETHOD(void, process_data, (j_decompress_ptr cinfo, + JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail)); +}; + +/* Decompression codec (decompressor proper) */ +struct jpeg_d_codec { + JMETHOD(void, calc_output_dimensions, (j_decompress_ptr cinfo)); + JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); + JMETHOD(int, consume_data, (j_decompress_ptr cinfo)); + JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo)); + JMETHOD(int, decompress_data, (j_decompress_ptr cinfo, + JSAMPIMAGE output_buf)); +}; + +/* Decompression postprocessing (color quantization buffer control) */ +struct jpeg_d_post_controller { + JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); + JMETHOD(void, post_process_data, (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, + JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail)); +}; + +/* Marker reading & parsing */ +struct jpeg_marker_reader { + JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo)); + /* Read markers until SOS or EOI. + * Returns same codes as are defined for jpeg_consume_input: + * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. + */ + JMETHOD(int, read_markers, (j_decompress_ptr cinfo)); + /* Read a restart marker --- exported for use by entropy decoder only */ + jpeg_marker_parser_method read_restart_marker; + + /* State of marker reader --- nominally internal, but applications + * supplying COM or APPn handlers might like to know the state. + */ + boolean saw_SOI; /* found SOI? */ + boolean saw_SOF; /* found SOF? */ + int next_restart_num; /* next restart number expected (0-7) */ + unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ +}; + +/* Upsampling (note that upsampler must also call color converter) */ +struct jpeg_upsampler { + JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, upsample, (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, + JDIMENSION *in_row_group_ctr, + JDIMENSION in_row_groups_avail, + JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, + JDIMENSION out_rows_avail)); + + boolean need_context_rows; /* TRUE if need rows above & below */ +}; + +/* Colorspace conversion */ +struct jpeg_color_deconverter { + JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, color_convert, (j_decompress_ptr cinfo, + JSAMPIMAGE input_buf, JDIMENSION input_row, + JSAMPARRAY output_buf, int num_rows)); +}; + +/* Color quantization or color precision reduction */ +struct jpeg_color_quantizer { + JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan)); + JMETHOD(void, color_quantize, (j_decompress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPARRAY output_buf, + int num_rows)); + JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); + JMETHOD(void, new_color_map, (j_decompress_ptr cinfo)); +}; + + +/* Miscellaneous useful macros */ + +#undef MAX +#define MAX(a,b) ((a) > (b) ? (a) : (b)) +#undef MIN +#define MIN(a,b) ((a) < (b) ? (a) : (b)) + + +/* We assume that right shift corresponds to signed division by 2 with + * rounding towards minus infinity. This is correct for typical "arithmetic + * shift" instructions that shift in copies of the sign bit. But some + * C compilers implement >> with an unsigned shift. For these machines you + * must define RIGHT_SHIFT_IS_UNSIGNED. + * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. + * It is only applied with constant shift counts. SHIFT_TEMPS must be + * included in the variables of any routine using RIGHT_SHIFT. + */ + +#ifdef RIGHT_SHIFT_IS_UNSIGNED +#define SHIFT_TEMPS INT32 shift_temp; +#define RIGHT_SHIFT(x,shft) \ + ((shift_temp = (x)) < 0 ? \ + (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \ + (shift_temp >> (shft))) +#else +#define SHIFT_TEMPS +#define RIGHT_SHIFT(x,shft) ((x) >> (shft)) +#endif + + +/* Short forms of external names for systems with brain-damaged linkers. */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jinit_c_codec jICCodec +#define jinit_c_diff_controller jICDiffC +#define jinit_lossy_c_codec jILossyC +#define jinit_lossless_c_codec jILosslessC +#define jinit_compress_master jICompress +#define jinit_c_master_control jICMaster +#define jinit_c_main_controller jICMainC +#define jinit_c_prep_controller jICPrepC +#define jinit_c_coef_controller jICCoefC +#define jinit_color_converter jICColor +#define jinit_downsampler jIDownsampler +#define jinit_forward_dct jIFDCT +#define jinit_shuff_encoder jISHEncoder +#define jinit_phuff_encoder jIPHEncoder +#define jinit_arith_encoder jIAEncoder +#define jinit_marker_writer jIMWriter +#define jinit_d_codec jIDCodec +#define jinit_lossy_d_codec jILossyD +#define jinit_lossless_d_codec jILosslsD +#define jinit_master_decompress jIDMaster +#define jinit_d_main_controller jIDMainC +#define jinit_d_coef_controller jIDCoefC +#define jinit_d_diff_controller jIDDiffC +#define jinit_d_post_controller jIDPostC +#define jinit_input_controller jIInCtlr +#define jinit_marker_reader jIMReader +#define jinit_shuff_decoder jISHDecoder +#define jinit_phuff_decoder jIPHDecoder +#define jinit_arith_decoder jIADecoder +#define jinit_lhuff_decoder jILHDecoder +#define jinit_undifferencer jIUndiff +#define jinit_d_scaler jIDScaler +#define jinit_inverse_dct jIIDCT +#define jinit_upsampler jIUpsampler +#define jinit_color_deconverter jIDColor +#define jinit_1pass_quantizer jI1Quant +#define jinit_2pass_quantizer jI2Quant +#define jinit_merged_upsampler jIMUpsampler +#define jinit_memory_mgr jIMemMgr +#define jdiv_round_up jDivRound +#define jround_up jRound +#define jcopy_sample_rows jCopySamples +#define jcopy_block_row jCopyBlocks +#define jzero_far jZeroFar +#define jpeg_zigzag_order jZIGTable +#define jpeg_natural_order jZAGTable +#endif /* NEED_SHORT_EXTERNAL_NAMES */ + + +/* Compression module initialization routines */ +EXTERN(void) jinit_c_codec JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_c_diff_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); +EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo, + boolean transcode_only)); +EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo, + boolean need_full_buffer)); +EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo, + boolean need_full_buffer)); +EXTERN(void) jinit_compressor JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo)); +EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo)); +/* Decompression module initialization routines */ +EXTERN(void) jinit_d_codec JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_d_diff_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); +EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo, + boolean need_full_buffer)); +EXTERN(void) jinit_decompressor JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo, + boolean need_full_buffer)); +EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo)); +EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo)); +/* Memory manager initialization */ +EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo)); + +/* Utility routines in jutils.c */ +EXTERN(long) jdiv_round_up JPP((long a, long b)); +EXTERN(long) jround_up JPP((long a, long b)); +EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row, + JSAMPARRAY output_array, int dest_row, + int num_rows, JDIMENSION num_cols)); +EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row, + JDIMENSION num_blocks)); +EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero)); +/* Constant tables in jutils.c */ +#if 0 /* This table is not actually needed in v6a */ +extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ +#endif +extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */ + +/* Suppress undefined-structure complaints if necessary. */ + +#ifdef INCOMPLETE_TYPES_BROKEN +#ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */ +struct jvirt_sarray_control { long dummy; }; +struct jvirt_barray_control { long dummy; }; +#endif +#endif /* INCOMPLETE_TYPES_BROKEN */ diff --git a/src/gdcmjpeg/jpeglib.h b/src/gdcmjpeg/jpeglib.h new file mode 100644 index 00000000..02c2d186 --- /dev/null +++ b/src/gdcmjpeg/jpeglib.h @@ -0,0 +1,1131 @@ +/* + * jpeglib.h + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file defines the application interface for the JPEG library. + * Most applications using the library need only include this file, + * and perhaps jerror.h if they want to know the exact error codes. + */ + +#ifndef JPEGLIB_H +#define JPEGLIB_H + +/* + * First we include the configuration files that record how this + * installation of the JPEG library is set up. jconfig.h can be + * generated automatically for many systems. jmorecfg.h contains + * manual configuration options that most people need not worry about. + */ + +#ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */ +#include "jconfig.h" /* widely used configuration options */ +#endif +#include "jmorecfg.h" /* seldom changed options */ + + +/* Version ID for the JPEG library. + * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60". + */ + +#define JPEG_LIB_VERSION 62 /* Version 6b */ + + +/* Various constants determining the sizes of things. + * All of these are specified by the JPEG standard, so don't change them + * if you want to be compatible. + */ + +#define DCTSIZE 8 /* The basic DCT block is 8x8 samples */ +#define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */ +#define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */ +#define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */ +#define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */ +#define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */ +#define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */ +/* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard; + * the PostScript DCT filter can emit files with many more than 10 data units + * per MCU. + * If you happen to run across such a file, you can up D_MAX_DATA_UNITS_IN_MCU + * to handle it. We even let you do this from the jconfig.h file. However, + * we strongly discourage changing C_MAX_DATA_UNITS_IN_MCU; just because Adobe + * sometimes emits noncompliant files doesn't mean you should too. + */ +#define C_MAX_DATA_UNITS_IN_MCU 10 /* compressor's limit on data units/MCU */ +#ifndef D_MAX_DATA_UNITS_IN_MCU +#define D_MAX_DATA_UNITS_IN_MCU 10 /* decompressor's limit on data units/MCU */ +#endif + + +/* Data structures for images (arrays of samples and of DCT coefficients). + * On 80x86 machines, the image arrays are too big for near pointers, + * but the pointer arrays can fit in near memory. + */ + +typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */ +typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */ +typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */ + +typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */ +typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */ +typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */ +typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */ + +typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */ + +typedef JDIFF FAR *JDIFFROW; /* pointer to one row of difference values */ +typedef JDIFFROW *JDIFFARRAY; /* ptr to some rows (a 2-D diff array) */ +typedef JDIFFARRAY *JDIFFIMAGE; /* a 3-D diff array: top index is color */ + + +/* Types for JPEG compression parameters and working tables. */ + + +/* DCT coefficient quantization tables. */ + +typedef struct { + /* This array gives the coefficient quantizers in natural array order + * (not the zigzag order in which they are stored in a JPEG DQT marker). + * CAUTION: IJG versions prior to v6a kept this array in zigzag order. + */ + UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */ + /* This field is used only during compression. It's initialized FALSE when + * the table is created, and set TRUE when it's been output to the file. + * You could suppress output of a table by setting this to TRUE. + * (See jpeg_suppress_tables for an example.) + */ + boolean sent_table; /* TRUE when table has been output */ +} JQUANT_TBL; + + +/* Huffman coding tables. */ + +typedef struct { + /* These two fields directly represent the contents of a JPEG DHT marker */ + UINT8 bits[17]; /* bits[k] = # of symbols with codes of */ + /* length k bits; bits[0] is unused */ + UINT8 huffval[256]; /* The symbols, in order of incr code length */ + /* This field is used only during compression. It's initialized FALSE when + * the table is created, and set TRUE when it's been output to the file. + * You could suppress output of a table by setting this to TRUE. + * (See jpeg_suppress_tables for an example.) + */ + boolean sent_table; /* TRUE when table has been output */ +} JHUFF_TBL; + + +/* Basic info about one component (color channel). */ + +typedef struct { + /* These values are fixed over the whole image. */ + /* For compression, they must be supplied by parameter setup; */ + /* for decompression, they are read from the SOF marker. */ + int component_id; /* identifier for this component (0..255) */ + int component_index; /* its index in SOF or cinfo->comp_info[] */ + int h_samp_factor; /* horizontal sampling factor (1..4) */ + int v_samp_factor; /* vertical sampling factor (1..4) */ + int quant_tbl_no; /* quantization table selector (0..3) */ + /* These values may vary between scans. */ + /* For compression, they must be supplied by parameter setup; */ + /* for decompression, they are read from the SOS marker. */ + /* The decompressor output side may not use these variables. */ + int dc_tbl_no; /* DC entropy table selector (0..3) */ + int ac_tbl_no; /* AC entropy table selector (0..3) */ + + /* Remaining fields should be treated as private by applications. */ + + /* These values are computed during compression or decompression startup: */ + /* Component's size in data units. + * Any dummy data units added to complete an MCU are not counted; therefore + * these values do not depend on whether a scan is interleaved or not. + */ + JDIMENSION width_in_data_units; + JDIMENSION height_in_data_units; + /* Size of a data unit in/output by the codec (in samples). Always + * data_unit for compression. For decompression this is the size of the + * output from one data_unit, reflecting any processing performed by the + * codec. For example, in the DCT-based codec, scaling may be applied + * during the IDCT step. Values of 1,2,4,8 are likely to be supported. + * Note that different components may have different codec_data_unit sizes. + */ + int codec_data_unit; + /* The downsampled dimensions are the component's actual, unpadded number + * of samples at the main buffer (preprocessing/compression interface), thus + * downsampled_width = ceil(image_width * Hi/Hmax) + * and similarly for height. For decompression, codec-based processing is + * included (ie, IDCT scaling), so + * downsampled_width = ceil(image_width * Hi/Hmax * codec_data_unit/data_unit) + */ + JDIMENSION downsampled_width; /* actual width in samples */ + JDIMENSION downsampled_height; /* actual height in samples */ + /* This flag is used only for decompression. In cases where some of the + * components will be ignored (eg grayscale output from YCbCr image), + * we can skip most computations for the unused components. + */ + boolean component_needed; /* do we need the value of this component? */ + + /* These values are computed before starting a scan of the component. */ + /* The decompressor output side may not use these variables. */ + int MCU_width; /* number of data units per MCU, horizontally */ + int MCU_height; /* number of data units per MCU, vertically */ + int MCU_data_units; /* MCU_width * MCU_height */ + int MCU_sample_width; /* MCU width in samples, MCU_width*codec_data_unit */ + int last_col_width; /* # of non-dummy data_units across in last MCU */ + int last_row_height; /* # of non-dummy data_units down in last MCU */ + + /* Saved quantization table for component; NULL if none yet saved. + * See jdinput.c comments about the need for this information. + * This field is currently used only for decompression. + */ + JQUANT_TBL * quant_table; + + /* Private per-component storage for DCT or IDCT subsystem. */ + void * dct_table; +} jpeg_component_info; + + +/* The script for encoding a multiple-scan file is an array of these: */ + +typedef struct { + int comps_in_scan; /* number of components encoded in this scan */ + int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */ + int Ss, Se; /* progressive JPEG spectral selection parms + lossless JPEG predictor select parm (Ss) */ + int Ah, Al; /* progressive JPEG successive approx. parms + lossless JPEG point transform parm (Al) */ +} jpeg_scan_info; + +/* The decompressor can save APPn and COM markers in a list of these: */ + +typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr; + +struct jpeg_marker_struct { + jpeg_saved_marker_ptr next; /* next in list, or NULL */ + UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */ + unsigned int original_length; /* # bytes of data in the file */ + unsigned int data_length; /* # bytes of data saved at data[] */ + JOCTET FAR * data; /* the data contained in the marker */ + /* the marker length word is not counted in data_length or original_length */ +}; + +/* Known codec processes. */ + +typedef enum { + JPROC_SEQUENTIAL, /* baseline/extended sequential DCT */ + JPROC_PROGRESSIVE, /* progressive DCT */ + JPROC_LOSSLESS /* lossless (sequential) */ +} J_CODEC_PROCESS; + +/* Known color spaces. */ + +typedef enum { + JCS_UNKNOWN, /* error/unspecified */ + JCS_GRAYSCALE, /* monochrome */ + JCS_RGB, /* red/green/blue */ + JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */ + JCS_CMYK, /* C/M/Y/K */ + JCS_YCCK /* Y/Cb/Cr/K */ +} J_COLOR_SPACE; + +/* DCT/IDCT algorithm options. */ + +typedef enum { + JDCT_ISLOW, /* slow but accurate integer algorithm */ + JDCT_IFAST, /* faster, less accurate integer method */ + JDCT_FLOAT /* floating-point: accurate, fast on fast HW */ +} J_DCT_METHOD; + +#ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */ +#define JDCT_DEFAULT JDCT_ISLOW +#endif +#ifndef JDCT_FASTEST /* may be overridden in jconfig.h */ +#define JDCT_FASTEST JDCT_IFAST +#endif + +/* Dithering options for decompression. */ + +typedef enum { + JDITHER_NONE, /* no dithering */ + JDITHER_ORDERED, /* simple ordered dither */ + JDITHER_FS /* Floyd-Steinberg error diffusion dither */ +} J_DITHER_MODE; + + +/* Common fields between JPEG compression and decompression master structs. */ + +#define jpeg_common_fields \ + struct jpeg_error_mgr * err; /* Error handler module */\ + struct jpeg_memory_mgr * mem; /* Memory manager module */\ + struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\ + void * client_data; /* Available for use by application */\ + boolean is_decompressor; /* So common code can tell which is which */\ + int global_state /* For checking call sequence validity */ + +/* Routines that are to be used by both halves of the library are declared + * to receive a pointer to this structure. There are no actual instances of + * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct. + */ +struct jpeg_common_struct { + jpeg_common_fields; /* Fields common to both master struct types */ + /* Additional fields follow in an actual jpeg_compress_struct or + * jpeg_decompress_struct. All three structs must agree on these + * initial fields! (This would be a lot cleaner in C++.) + */ +}; + +typedef struct jpeg_common_struct * j_common_ptr; +typedef struct jpeg_compress_struct * j_compress_ptr; +typedef struct jpeg_decompress_struct * j_decompress_ptr; + + +/* Master record for a compression instance */ + +struct jpeg_compress_struct { + jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */ + + /* Destination for compressed data */ + struct jpeg_destination_mgr * dest; + + /* Description of source image --- these fields must be filled in by + * outer application before starting compression. in_color_space must + * be correct before you can even call jpeg_set_defaults(). + */ + + JDIMENSION image_width; /* input image width */ + JDIMENSION image_height; /* input image height */ + int input_components; /* # of color components in input image */ + J_COLOR_SPACE in_color_space; /* colorspace of input image */ + + double input_gamma; /* image gamma of input image */ + + /* Compression parameters --- these fields must be set before calling + * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to + * initialize everything to reasonable defaults, then changing anything + * the application specifically wants to change. That way you won't get + * burnt when new parameters are added. Also note that there are several + * helper routines to simplify changing parameters. + */ + + boolean lossless; /* TRUE=lossless encoding, FALSE=lossy */ + + int data_precision; /* bits of precision in image data */ + + int num_components; /* # of color components in JPEG image */ + J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ + + jpeg_component_info * comp_info; + /* comp_info[i] describes component that appears i'th in SOF */ + + JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; + /* ptrs to coefficient quantization tables, or NULL if not defined */ + + JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; + JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; + /* ptrs to Huffman coding tables, or NULL if not defined */ + + UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ + UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ + UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ + + int num_scans; /* # of entries in scan_info array */ + const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */ + /* The default value of scan_info is NULL, which causes a single-scan + * sequential JPEG file to be emitted. To create a multi-scan file, + * set num_scans and scan_info to point to an array of scan definitions. + */ + + boolean raw_data_in; /* TRUE=caller supplies downsampled data */ + boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ + boolean optimize_coding; /* TRUE=optimize entropy encoding parms */ + boolean CCIR601_sampling; /* TRUE=first samples are cosited */ + int smoothing_factor; /* 1..100, or 0 for no input smoothing */ + J_DCT_METHOD dct_method; /* DCT algorithm selector */ + + /* The restart interval can be specified in absolute MCUs by setting + * restart_interval, or in MCU rows by setting restart_in_rows + * (in which case the correct restart_interval will be figured + * for each scan). + */ + unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */ + int restart_in_rows; /* if > 0, MCU rows per restart interval */ + + /* Parameters controlling emission of special markers. */ + + boolean write_JFIF_header; /* should a JFIF marker be written? */ + UINT8 JFIF_major_version; /* What to write for the JFIF version number */ + UINT8 JFIF_minor_version; + /* These three values are not used by the JPEG code, merely copied */ + /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */ + /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */ + /* ratio is defined by X_density/Y_density even when density_unit=0. */ + UINT8 density_unit; /* JFIF code for pixel size units */ + UINT16 X_density; /* Horizontal pixel density */ + UINT16 Y_density; /* Vertical pixel density */ + boolean write_Adobe_marker; /* should an Adobe marker be written? */ + + /* State variable: index of next scanline to be written to + * jpeg_write_scanlines(). Application may use this to control its + * processing loop, e.g., "while (next_scanline < image_height)". + */ + + JDIMENSION next_scanline; /* 0 .. image_height-1 */ + + /* Remaining fields are known throughout compressor, but generally + * should not be touched by a surrounding application. + */ + + /* + * These fields are computed during compression startup + */ + int data_unit; /* size of data unit in samples */ + J_CODEC_PROCESS process; /* encoding process of JPEG image */ + + int max_h_samp_factor; /* largest h_samp_factor */ + int max_v_samp_factor; /* largest v_samp_factor */ + + JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to codec */ + /* The codec receives data in units of MCU rows as defined for fully + * interleaved scans (whether the JPEG file is interleaved or not). + * There are v_samp_factor * data_unit sample rows of each component in an + * "iMCU" (interleaved MCU) row. + */ + + /* + * These fields are valid during any one scan. + * They describe the components and MCUs actually appearing in the scan. + */ + int comps_in_scan; /* # of JPEG components in this scan */ + jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; + /* *cur_comp_info[i] describes component that appears i'th in SOS */ + + JDIMENSION MCUs_per_row; /* # of MCUs across the image */ + JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ + + int data_units_in_MCU; /* # of data units per MCU */ + int MCU_membership[C_MAX_DATA_UNITS_IN_MCU]; + /* MCU_membership[i] is index in cur_comp_info of component owning */ + /* i'th block in an MCU */ + + int Ss, Se, Ah, Al; /* progressive/lossless JPEG parameters for scan */ + + /* + * Links to compression subobjects (methods and private variables of modules) + */ + struct jpeg_comp_master * master; + struct jpeg_c_main_controller * main; + struct jpeg_c_prep_controller * prep; + struct jpeg_c_codec * codec; + struct jpeg_marker_writer * marker; + struct jpeg_color_converter * cconvert; + struct jpeg_downsampler * downsample; + jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */ + int script_space_size; +}; + + +/* Master record for a decompression instance */ + +struct jpeg_decompress_struct { + jpeg_common_fields; /* Fields shared with jpeg_compress_struct */ + + /* Source of compressed data */ + struct jpeg_source_mgr * src; + + /* Basic description of image --- filled in by jpeg_read_header(). */ + /* Application may inspect these values to decide how to process image. */ + + JDIMENSION image_width; /* nominal image width (from SOF marker) */ + JDIMENSION image_height; /* nominal image height */ + int num_components; /* # of color components in JPEG image */ + J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */ + + /* Decompression processing parameters --- these fields must be set before + * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes + * them to default values. + */ + + J_COLOR_SPACE out_color_space; /* colorspace for output */ + + unsigned int scale_num, scale_denom; /* fraction by which to scale image */ + + double output_gamma; /* image gamma wanted in output */ + + boolean buffered_image; /* TRUE=multiple output passes */ + boolean raw_data_out; /* TRUE=downsampled data wanted */ + + J_DCT_METHOD dct_method; /* IDCT algorithm selector */ + boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */ + boolean do_block_smoothing; /* TRUE=apply interblock smoothing */ + + boolean quantize_colors; /* TRUE=colormapped output wanted */ + /* the following are ignored if not quantize_colors: */ + J_DITHER_MODE dither_mode; /* type of color dithering to use */ + boolean two_pass_quantize; /* TRUE=use two-pass color quantization */ + int desired_number_of_colors; /* max # colors to use in created colormap */ + /* these are significant only in buffered-image mode: */ + boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */ + boolean enable_external_quant;/* enable future use of external colormap */ + boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */ + + /* Description of actual output image that will be returned to application. + * These fields are computed by jpeg_start_decompress(). + * You can also use jpeg_calc_output_dimensions() to determine these values + * in advance of calling jpeg_start_decompress(). + */ + + JDIMENSION output_width; /* scaled image width */ + JDIMENSION output_height; /* scaled image height */ + int out_color_components; /* # of color components in out_color_space */ + int output_components; /* # of color components returned */ + /* output_components is 1 (a colormap index) when quantizing colors; + * otherwise it equals out_color_components. + */ + int rec_outbuf_height; /* min recommended height of scanline buffer */ + /* If the buffer passed to jpeg_read_scanlines() is less than this many rows + * high, space and time will be wasted due to unnecessary data copying. + * Usually rec_outbuf_height will be 1 or 2, at most 4. + */ + + /* When quantizing colors, the output colormap is described by these fields. + * The application can supply a colormap by setting colormap non-NULL before + * calling jpeg_start_decompress; otherwise a colormap is created during + * jpeg_start_decompress or jpeg_start_output. + * The map has out_color_components rows and actual_number_of_colors columns. + */ + int actual_number_of_colors; /* number of entries in use */ + JSAMPARRAY colormap; /* The color map as a 2-D pixel array */ + + /* State variables: these variables indicate the progress of decompression. + * The application may examine these but must not modify them. + */ + + /* Row index of next scanline to be read from jpeg_read_scanlines(). + * Application may use this to control its processing loop, e.g., + * "while (output_scanline < output_height)". + */ + JDIMENSION output_scanline; /* 0 .. output_height-1 */ + + /* Current input scan number and number of iMCU rows completed in scan. + * These indicate the progress of the decompressor input side. + */ + int input_scan_number; /* Number of SOS markers seen so far */ + JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */ + + /* The "output scan number" is the notional scan being displayed by the + * output side. The decompressor will not allow output scan/row number + * to get ahead of input scan/row, but it can fall arbitrarily far behind. + */ + int output_scan_number; /* Nominal scan number being displayed */ + JDIMENSION output_iMCU_row; /* Number of iMCU rows read */ + + /* Current progression status. coef_bits[c][i] indicates the precision + * with which component c's DCT coefficient i (in zigzag order) is known. + * It is -1 when no data has yet been received, otherwise it is the point + * transform (shift) value for the most recent scan of the coefficient + * (thus, 0 at completion of the progression). + * This pointer is NULL when reading a non-progressive file. + */ + int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */ + + /* Internal JPEG parameters --- the application usually need not look at + * these fields. Note that the decompressor output side may not use + * any parameters that can change between scans. + */ + + /* Quantization and Huffman tables are carried forward across input + * datastreams when processing abbreviated JPEG datastreams. + */ + + JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; + /* ptrs to coefficient quantization tables, or NULL if not defined */ + + JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; + JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; + /* ptrs to Huffman coding tables, or NULL if not defined */ + + /* These parameters are never carried across datastreams, since they + * are given in SOF/SOS markers or defined to be reset by SOI. + */ + + int data_precision; /* bits of precision in image data */ + + jpeg_component_info * comp_info; + /* comp_info[i] describes component that appears i'th in SOF */ + + boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */ + + UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ + UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ + UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ + + unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */ + + /* These fields record data obtained from optional markers recognized by + * the JPEG library. + */ + boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */ + /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */ + UINT8 JFIF_major_version; /* JFIF version number */ + UINT8 JFIF_minor_version; + UINT8 density_unit; /* JFIF code for pixel size units */ + UINT16 X_density; /* Horizontal pixel density */ + UINT16 Y_density; /* Vertical pixel density */ + boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */ + UINT8 Adobe_transform; /* Color transform code from Adobe marker */ + + boolean CCIR601_sampling; /* TRUE=first samples are cosited */ + + /* Aside from the specific data retained from APPn markers known to the + * library, the uninterpreted contents of any or all APPn and COM markers + * can be saved in a list for examination by the application. + */ + jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */ + + /* Remaining fields are known throughout decompressor, but generally + * should not be touched by a surrounding application. + */ + + /* + * These fields are computed during decompression startup + */ + int data_unit; /* size of data unit in samples */ + J_CODEC_PROCESS process; /* decoding process of JPEG image */ + + int max_h_samp_factor; /* largest h_samp_factor */ + int max_v_samp_factor; /* largest v_samp_factor */ + + int min_codec_data_unit; /* smallest codec_data_unit of any component */ + + JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ + /* The codec's input and output progress is measured in units of "iMCU" + * (interleaved MCU) rows. These are the same as MCU rows in fully + * interleaved JPEG scans, but are used whether the scan is interleaved + * or not. We define an iMCU row as v_samp_factor data_unit rows of each + * component. Therefore, the codec output contains + * v_samp_factor*codec_data_unit sample rows of a component per iMCU row. + */ + + JSAMPLE * sample_range_limit; /* table for fast range-limiting */ + + /* + * These fields are valid during any one scan. + * They describe the components and MCUs actually appearing in the scan. + * Note that the decompressor output side must not use these fields. + */ + int comps_in_scan; /* # of JPEG components in this scan */ + jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN]; + /* *cur_comp_info[i] describes component that appears i'th in SOS */ + + JDIMENSION MCUs_per_row; /* # of MCUs across the image */ + JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */ + + int data_units_in_MCU; /* # of data _units per MCU */ + int MCU_membership[D_MAX_DATA_UNITS_IN_MCU]; + /* MCU_membership[i] is index in cur_comp_info of component owning */ + /* i'th data unit in an MCU */ + + int Ss, Se, Ah, Al; /* progressive/lossless JPEG parms for scan */ + + /* This field is shared between entropy decoder and marker parser. + * It is either zero or the code of a JPEG marker that has been + * read from the data source, but has not yet been processed. + */ + int unread_marker; + + /* + * Links to decompression subobjects (methods, private variables of modules) + */ + struct jpeg_decomp_master * master; + struct jpeg_d_main_controller * main; + struct jpeg_d_codec * codec; + struct jpeg_d_post_controller * post; + struct jpeg_input_controller * inputctl; + struct jpeg_marker_reader * marker; + struct jpeg_upsampler * upsample; + struct jpeg_color_deconverter * cconvert; + struct jpeg_color_quantizer * cquantize; +}; + + +/* "Object" declarations for JPEG modules that may be supplied or called + * directly by the surrounding application. + * As with all objects in the JPEG library, these structs only define the + * publicly visible methods and state variables of a module. Additional + * private fields may exist after the public ones. + */ + + +/* Error handler object */ + +struct jpeg_error_mgr { + /* Error exit handler: does not return to caller */ + JMETHOD(void, error_exit, (j_common_ptr cinfo)); + /* Conditionally emit a trace or warning message */ + JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level)); + /* Routine that actually outputs a trace or error message */ + JMETHOD(void, output_message, (j_common_ptr cinfo)); + /* Format a message string for the most recent JPEG error or message */ + JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer)); +#define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */ + /* Reset error state variables at start of a new image */ + JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo)); + + /* The message ID code and any parameters are saved here. + * A message can have one string parameter or up to 8 int parameters. + */ + int msg_code; +#define JMSG_STR_PARM_MAX 80 + union { + int i[8]; + char s[JMSG_STR_PARM_MAX]; + } msg_parm; + + /* Standard state variables for error facility */ + + int trace_level; /* max msg_level that will be displayed */ + + /* For recoverable corrupt-data errors, we emit a warning message, + * but keep going unless emit_message chooses to abort. emit_message + * should count warnings in num_warnings. The surrounding application + * can check for bad data by seeing if num_warnings is nonzero at the + * end of processing. + */ + long num_warnings; /* number of corrupt-data warnings */ + + /* These fields point to the table(s) of error message strings. + * An application can change the table pointer to switch to a different + * message list (typically, to change the language in which errors are + * reported). Some applications may wish to add additional error codes + * that will be handled by the JPEG library error mechanism; the second + * table pointer is used for this purpose. + * + * First table includes all errors generated by JPEG library itself. + * Error code 0 is reserved for a "no such error string" message. + */ + const char * const * jpeg_message_table; /* Library errors */ + int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */ + /* Second table can be added by application (see cjpeg/djpeg for example). + * It contains strings numbered first_addon_message..last_addon_message. + */ + const char * const * addon_message_table; /* Non-library errors */ + int first_addon_message; /* code for first string in addon table */ + int last_addon_message; /* code for last string in addon table */ +}; + + +/* Progress monitor object */ + +struct jpeg_progress_mgr { + JMETHOD(void, progress_monitor, (j_common_ptr cinfo)); + + long pass_counter; /* work units completed in this pass */ + long pass_limit; /* total number of work units in this pass */ + int completed_passes; /* passes completed so far */ + int total_passes; /* total number of passes expected */ +}; + + +/* Data destination object for compression */ + +struct jpeg_destination_mgr { + JOCTET * next_output_byte; /* => next byte to write in buffer */ + size_t free_in_buffer; /* # of byte spaces remaining in buffer */ + + JMETHOD(void, init_destination, (j_compress_ptr cinfo)); + JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo)); + JMETHOD(void, term_destination, (j_compress_ptr cinfo)); +}; + + +/* Data source object for decompression */ + +struct jpeg_source_mgr { + const JOCTET * next_input_byte; /* => next byte to read from buffer */ + size_t bytes_in_buffer; /* # of bytes remaining in buffer */ + + JMETHOD(void, init_source, (j_decompress_ptr cinfo)); + JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo)); + JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes)); + JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired)); + JMETHOD(void, term_source, (j_decompress_ptr cinfo)); +}; + + +/* Memory manager object. + * Allocates "small" objects (a few K total), "large" objects (tens of K), + * and "really big" objects (virtual arrays with backing store if needed). + * The memory manager does not allow individual objects to be freed; rather, + * each created object is assigned to a pool, and whole pools can be freed + * at once. This is faster and more convenient than remembering exactly what + * to free, especially where malloc()/free() are not too speedy. + * NB: alloc routines never return NULL. They exit to error_exit if not + * successful. + */ + +#define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */ +#define JPOOL_IMAGE 1 /* lasts until done with image/datastream */ +#define JPOOL_NUMPOOLS 2 + +typedef struct jvirt_sarray_control * jvirt_sarray_ptr; +typedef struct jvirt_barray_control * jvirt_barray_ptr; + + +#ifdef C_LOSSLESS_SUPPORTED +#define NEED_DARRAY +#else +#ifdef D_LOSSLESS_SUPPORTED +#define NEED_DARRAY +#endif +#endif + +struct jpeg_memory_mgr { + /* Method pointers */ + JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id, + size_t sizeofobject)); + JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id, + size_t sizeofobject)); + JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id, + JDIMENSION samplesperrow, + JDIMENSION numrows)); + JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id, + JDIMENSION blocksperrow, + JDIMENSION numrows)); +#ifdef NEED_DARRAY + JMETHOD(JDIFFARRAY, alloc_darray, (j_common_ptr cinfo, int pool_id, + JDIMENSION diffsperrow, + JDIMENSION numrows)); +#endif + JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo, + int pool_id, + boolean pre_zero, + JDIMENSION samplesperrow, + JDIMENSION numrows, + JDIMENSION maxaccess)); + JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo, + int pool_id, + boolean pre_zero, + JDIMENSION blocksperrow, + JDIMENSION numrows, + JDIMENSION maxaccess)); + JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo)); + JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo, + jvirt_sarray_ptr ptr, + JDIMENSION start_row, + JDIMENSION num_rows, + boolean writable)); + JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo, + jvirt_barray_ptr ptr, + JDIMENSION start_row, + JDIMENSION num_rows, + boolean writable)); + JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id)); + JMETHOD(void, self_destruct, (j_common_ptr cinfo)); + + /* Limit on memory allocation for this JPEG object. (Note that this is + * merely advisory, not a guaranteed maximum; it only affects the space + * used for virtual-array buffers.) May be changed by outer application + * after creating the JPEG object. + */ + long max_memory_to_use; + + /* Maximum allocation request accepted by alloc_large. */ + long max_alloc_chunk; +}; + + +/* Routine signature for application-supplied marker processing methods. + * Need not pass marker code since it is stored in cinfo->unread_marker. + */ +typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); + + +/* Declarations for routines called by application. + * The JPP macro hides prototype parameters from compilers that can't cope. + * Note JPP requires double parentheses. + */ + +#ifdef HAVE_PROTOTYPES +#define JPP(arglist) arglist +#else +#define JPP(arglist) () +#endif + + +/* Short forms of external names for systems with brain-damaged linkers. + * We shorten external names to be unique in the first six letters, which + * is good enough for all known systems. + * (If your compiler itself needs names to be unique in less than 15 + * characters, you are out of luck. Get a better compiler.) + */ + +#ifdef NEED_SHORT_EXTERNAL_NAMES +#define jpeg_std_error jStdError +#define jpeg_CreateCompress jCreaCompress +#define jpeg_CreateDecompress jCreaDecompress +#define jpeg_destroy_compress jDestCompress +#define jpeg_destroy_decompress jDestDecompress +#define jpeg_stdio_dest jStdDest +#define jpeg_stdio_src jStdSrc +#define jpeg_set_defaults jSetDefaults +#define jpeg_set_colorspace jSetColorspace +#define jpeg_default_colorspace jDefColorspace +#define jpeg_set_quality jSetQuality +#define jpeg_set_linear_quality jSetLQuality +#define jpeg_add_quant_table jAddQuantTable +#define jpeg_quality_scaling jQualityScaling +#define jpeg_simple_lossless jSimLossless +#define jpeg_simple_progression jSimProgress +#define jpeg_suppress_tables jSuppressTables +#define jpeg_alloc_quant_table jAlcQTable +#define jpeg_alloc_huff_table jAlcHTable +#define jpeg_start_compress jStrtCompress +#define jpeg_write_scanlines jWrtScanlines +#define jpeg_finish_compress jFinCompress +#define jpeg_write_raw_data jWrtRawData +#define jpeg_write_marker jWrtMarker +#define jpeg_write_m_header jWrtMHeader +#define jpeg_write_m_byte jWrtMByte +#define jpeg_write_tables jWrtTables +#define jpeg_read_header jReadHeader +#define jpeg_start_decompress jStrtDecompress +#define jpeg_read_scanlines jReadScanlines +#define jpeg_finish_decompress jFinDecompress +#define jpeg_read_raw_data jReadRawData +#define jpeg_has_multiple_scans jHasMultScn +#define jpeg_start_output jStrtOutput +#define jpeg_finish_output jFinOutput +#define jpeg_input_complete jInComplete +#define jpeg_new_colormap jNewCMap +#define jpeg_consume_input jConsumeInput +#define jpeg_calc_output_dimensions jCalcDimensions +#define jpeg_save_markers jSaveMarkers +#define jpeg_set_marker_processor jSetMarker +#define jpeg_read_coefficients jReadCoefs +#define jpeg_write_coefficients jWrtCoefs +#define jpeg_copy_critical_parameters jCopyCrit +#define jpeg_abort_compress jAbrtCompress +#define jpeg_abort_decompress jAbrtDecompress +#define jpeg_abort jAbort +#define jpeg_destroy jDestroy +#define jpeg_resync_to_restart jResyncRestart +#endif /* NEED_SHORT_EXTERNAL_NAMES */ + + +/* Default error-management setup */ +EXTERN(struct jpeg_error_mgr *) jpeg_std_error + JPP((struct jpeg_error_mgr * err)); + +/* Initialization of JPEG compression objects. + * jpeg_create_compress() and jpeg_create_decompress() are the exported + * names that applications should call. These expand to calls on + * jpeg_CreateCompress and jpeg_CreateDecompress with additional information + * passed for version mismatch checking. + * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx. + */ +#define jpeg_create_compress(cinfo) \ + jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \ + (size_t) sizeof(struct jpeg_compress_struct)) +#define jpeg_create_decompress(cinfo) \ + jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \ + (size_t) sizeof(struct jpeg_decompress_struct)) +EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo, + int version, size_t structsize)); +EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo, + int version, size_t structsize)); +/* Destruction of JPEG compression objects */ +EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo)); +EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo)); + +/* Standard data source and destination managers: stdio streams. */ +/* Caller is responsible for opening the file before and closing after. */ +EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile)); +EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile)); + +/* Default parameter setup for compression */ +EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo)); +/* Compression parameter setup aids */ +EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo, + J_COLOR_SPACE colorspace)); +EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo)); +EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, + boolean force_baseline)); +EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, + int scale_factor, + boolean force_baseline)); +EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, + const unsigned int *basic_table, + int scale_factor, + boolean force_baseline)); +EXTERN(int) jpeg_quality_scaling JPP((int quality)); +EXTERN(void) jpeg_simple_lossless JPP((j_compress_ptr cinfo, + int predictor, int point_transform)); +EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo)); +EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo, + boolean suppress)); +EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo)); +EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo)); + +/* Main entry points for compression */ +EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo, + boolean write_all_tables)); +EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, + JSAMPARRAY scanlines, + JDIMENSION num_lines)); +EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); + +/* Replaces jpeg_write_scanlines when writing raw downsampled data. */ +EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, + JSAMPIMAGE data, + JDIMENSION num_lines)); + +/* Write a special marker. See libjpeg.doc concerning safe usage. */ +EXTERN(void) jpeg_write_marker + JPP((j_compress_ptr cinfo, int marker, + const JOCTET * dataptr, unsigned int datalen)); +/* Same, but piecemeal. */ +EXTERN(void) jpeg_write_m_header + JPP((j_compress_ptr cinfo, int marker, unsigned int datalen)); +EXTERN(void) jpeg_write_m_byte + JPP((j_compress_ptr cinfo, int val)); + +/* Alternate compression function: just write an abbreviated table file */ +EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo)); + +/* Decompression startup: read start of JPEG datastream to see what's there */ +EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo, + boolean require_image)); +/* Return value is one of: */ +#define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */ +#define JPEG_HEADER_OK 1 /* Found valid image datastream */ +#define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */ +/* If you pass require_image = TRUE (normal case), you need not check for + * a TABLES_ONLY return code; an abbreviated file will cause an error exit. + * JPEG_SUSPENDED is only possible if you use a data source module that can + * give a suspension return (the stdio source module doesn't). + */ + +/* Main entry points for decompression */ +EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo)); +EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo, + JSAMPARRAY scanlines, + JDIMENSION max_lines)); +EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo)); + +/* Replaces jpeg_read_scanlines when reading raw downsampled data. */ +EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo, + JSAMPIMAGE data, + JDIMENSION max_lines)); + +/* Additional entry points for buffered-image mode. */ +EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo)); +EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo, + int scan_number)); +EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo)); +EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo)); +EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo)); +EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo)); +/* Return value is one of: */ +/* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */ +#define JPEG_REACHED_SOS 1 /* Reached start of new scan */ +#define JPEG_REACHED_EOI 2 /* Reached end of image */ +#define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */ +#define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */ + +/* Precalculate output dimensions for current decompression parameters. */ +EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo)); + +/* Control saving of COM and APPn markers into marker_list. */ +EXTERN(void) jpeg_save_markers + JPP((j_decompress_ptr cinfo, int marker_code, + unsigned int length_limit)); + +/* Install a special processing method for COM or APPn markers. */ +EXTERN(void) jpeg_set_marker_processor + JPP((j_decompress_ptr cinfo, int marker_code, + jpeg_marker_parser_method routine)); + +/* Read or write raw DCT coefficients --- useful for lossless transcoding. */ +EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo)); +EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo, + jvirt_barray_ptr * coef_arrays)); +EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo, + j_compress_ptr dstinfo)); + +/* If you choose to abort compression or decompression before completing + * jpeg_finish_(de)compress, then you need to clean up to release memory, + * temporary files, etc. You can just call jpeg_destroy_(de)compress + * if you're done with the JPEG object, but if you want to clean it up and + * reuse it, call this: + */ +EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo)); +EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo)); + +/* Generic versions of jpeg_abort and jpeg_destroy that work on either + * flavor of JPEG object. These may be more convenient in some places. + */ +EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo)); +EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo)); + +/* Default restart-marker-resync procedure for use by data source modules */ +EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo, + int desired)); + + +/* These marker codes are exported since applications and data source modules + * are likely to want to use them. + */ + +#define JPEG_RST0 0xD0 /* RST0 marker code */ +#define JPEG_EOI 0xD9 /* EOI marker code */ +#define JPEG_APP0 0xE0 /* APP0 marker code */ +#define JPEG_COM 0xFE /* COM marker code */ + + +/* If we have a brain-damaged compiler that emits warnings (or worse, errors) + * for structure definitions that are never filled in, keep it quiet by + * supplying dummy definitions for the various substructures. + */ + +#ifdef INCOMPLETE_TYPES_BROKEN +#ifndef JPEG_INTERNALS /* will be defined in jpegint.h */ +struct jvirt_sarray_control { long dummy; }; +struct jvirt_barray_control { long dummy; }; +struct jpeg_comp_master { long dummy; }; +struct jpeg_c_main_controller { long dummy; }; +struct jpeg_c_prep_controller { long dummy; }; +struct jpeg_c_coef_controller { long dummy; }; +struct jpeg_marker_writer { long dummy; }; +struct jpeg_color_converter { long dummy; }; +struct jpeg_downsampler { long dummy; }; +struct jpeg_forward_dct { long dummy; }; +struct jpeg_entropy_encoder { long dummy; }; +struct jpeg_decomp_master { long dummy; }; +struct jpeg_d_main_controller { long dummy; }; +struct jpeg_d_coef_controller { long dummy; }; +struct jpeg_d_post_controller { long dummy; }; +struct jpeg_input_controller { long dummy; }; +struct jpeg_marker_reader { long dummy; }; +struct jpeg_entropy_decoder { long dummy; }; +struct jpeg_inverse_dct { long dummy; }; +struct jpeg_upsampler { long dummy; }; +struct jpeg_color_deconverter { long dummy; }; +struct jpeg_color_quantizer { long dummy; }; +#endif /* JPEG_INTERNALS */ +#endif /* INCOMPLETE_TYPES_BROKEN */ + + +/* + * The JPEG library modules define JPEG_INTERNALS before including this file. + * The internal structure declarations are read only when that is true. + * Applications using the library should not include jpegint.h, but may wish + * to include jerror.h. + */ + +#ifdef JPEG_INTERNALS +#include "jpegint.h" /* fetch private declarations */ +#include "jerror.h" /* fetch error codes too */ +#endif + +#endif /* JPEGLIB_H */ diff --git a/src/gdcmjpeg/jquant1.c b/src/gdcmjpeg/jquant1.c new file mode 100644 index 00000000..a5abd0a8 --- /dev/null +++ b/src/gdcmjpeg/jquant1.c @@ -0,0 +1,860 @@ +/* + * jquant1.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains 1-pass color quantization (color mapping) routines. + * These routines provide mapping to a fixed color map using equally spaced + * color values. Optional Floyd-Steinberg or ordered dithering is available. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + +#ifdef QUANT_1PASS_SUPPORTED + + +/* + * The main purpose of 1-pass quantization is to provide a fast, if not very + * high quality, colormapped output capability. A 2-pass quantizer usually + * gives better visual quality; however, for quantized grayscale output this + * quantizer is perfectly adequate. Dithering is highly recommended with this + * quantizer, though you can turn it off if you really want to. + * + * In 1-pass quantization the colormap must be chosen in advance of seeing the + * image. We use a map consisting of all combinations of Ncolors[i] color + * values for the i'th component. The Ncolors[] values are chosen so that + * their product, the total number of colors, is no more than that requested. + * (In most cases, the product will be somewhat less.) + * + * Since the colormap is orthogonal, the representative value for each color + * component can be determined without considering the other components; + * then these indexes can be combined into a colormap index by a standard + * N-dimensional-array-subscript calculation. Most of the arithmetic involved + * can be precalculated and stored in the lookup table colorindex[]. + * colorindex[i][j] maps pixel value j in component i to the nearest + * representative value (grid plane) for that component; this index is + * multiplied by the array stride for component i, so that the + * index of the colormap entry closest to a given pixel value is just + * sum( colorindex[component-number][pixel-component-value] ) + * Aside from being fast, this scheme allows for variable spacing between + * representative values with no additional lookup cost. + * + * If gamma correction has been applied in color conversion, it might be wise + * to adjust the color grid spacing so that the representative colors are + * equidistant in linear space. At this writing, gamma correction is not + * implemented by jdcolor, so nothing is done here. + */ + + +/* Declarations for ordered dithering. + * + * We use a standard 16x16 ordered dither array. The basic concept of ordered + * dithering is described in many references, for instance Dale Schumacher's + * chapter II.2 of Graphics Gems II (James Arvo, ed. Academic Press, 1991). + * In place of Schumacher's comparisons against a "threshold" value, we add a + * "dither" value to the input pixel and then round the result to the nearest + * output value. The dither value is equivalent to (0.5 - threshold) times + * the distance between output values. For ordered dithering, we assume that + * the output colors are equally spaced; if not, results will probably be + * worse, since the dither may be too much or too little at a given point. + * + * The normal calculation would be to form pixel value + dither, range-limit + * this to 0..MAXJSAMPLE, and then index into the colorindex table as usual. + * We can skip the separate range-limiting step by extending the colorindex + * table in both directions. + */ + +#define ODITHER_SIZE 16 /* dimension of dither matrix */ +/* NB: if ODITHER_SIZE is not a power of 2, ODITHER_MASK uses will break */ +#define ODITHER_CELLS (ODITHER_SIZE*ODITHER_SIZE) /* # cells in matrix */ +#define ODITHER_MASK (ODITHER_SIZE-1) /* mask for wrapping around counters */ + +typedef int ODITHER_MATRIX[ODITHER_SIZE][ODITHER_SIZE]; +typedef int (*ODITHER_MATRIX_PTR)[ODITHER_SIZE]; + +static const UINT8 base_dither_matrix[ODITHER_SIZE][ODITHER_SIZE] = { + /* Bayer's order-4 dither array. Generated by the code given in + * Stephen Hawley's article "Ordered Dithering" in Graphics Gems I. + * The values in this array must range from 0 to ODITHER_CELLS-1. + */ + { 0,192, 48,240, 12,204, 60,252, 3,195, 51,243, 15,207, 63,255 }, + { 128, 64,176,112,140, 76,188,124,131, 67,179,115,143, 79,191,127 }, + { 32,224, 16,208, 44,236, 28,220, 35,227, 19,211, 47,239, 31,223 }, + { 160, 96,144, 80,172,108,156, 92,163, 99,147, 83,175,111,159, 95 }, + { 8,200, 56,248, 4,196, 52,244, 11,203, 59,251, 7,199, 55,247 }, + { 136, 72,184,120,132, 68,180,116,139, 75,187,123,135, 71,183,119 }, + { 40,232, 24,216, 36,228, 20,212, 43,235, 27,219, 39,231, 23,215 }, + { 168,104,152, 88,164,100,148, 84,171,107,155, 91,167,103,151, 87 }, + { 2,194, 50,242, 14,206, 62,254, 1,193, 49,241, 13,205, 61,253 }, + { 130, 66,178,114,142, 78,190,126,129, 65,177,113,141, 77,189,125 }, + { 34,226, 18,210, 46,238, 30,222, 33,225, 17,209, 45,237, 29,221 }, + { 162, 98,146, 82,174,110,158, 94,161, 97,145, 81,173,109,157, 93 }, + { 10,202, 58,250, 6,198, 54,246, 9,201, 57,249, 5,197, 53,245 }, + { 138, 74,186,122,134, 70,182,118,137, 73,185,121,133, 69,181,117 }, + { 42,234, 26,218, 38,230, 22,214, 41,233, 25,217, 37,229, 21,213 }, + { 170,106,154, 90,166,102,150, 86,169,105,153, 89,165,101,149, 85 } +}; + + +/* Declarations for Floyd-Steinberg dithering. + * + * Errors are accumulated into the array fserrors[], at a resolution of + * 1/16th of a pixel count. The error at a given pixel is propagated + * to its not-yet-processed neighbors using the standard F-S fractions, + * ... (here) 7/16 + * 3/16 5/16 1/16 + * We work left-to-right on even rows, right-to-left on odd rows. + * + * We can get away with a single array (holding one row's worth of errors) + * by using it to store the current row's errors at pixel columns not yet + * processed, but the next row's errors at columns already processed. We + * need only a few extra variables to hold the errors immediately around the + * current column. (If we are lucky, those variables are in registers, but + * even if not, they're probably cheaper to access than array elements are.) + * + * The fserrors[] array is indexed [component#][position]. + * We provide (#columns + 2) entries per component; the extra entry at each + * end saves us from special-casing the first and last pixels. + * + * Note: on a wide image, we might not have enough room in a PC's near data + * segment to hold the error array; so it is allocated with alloc_large. + */ + +#if BITS_IN_JSAMPLE == 8 +typedef INT16 FSERROR; /* 16 bits should be enough */ +typedef int LOCFSERROR; /* use 'int' for calculation temps */ +#else +typedef INT32 FSERROR; /* may need more than 16 bits */ +typedef INT32 LOCFSERROR; /* be sure calculation temps are big enough */ +#endif + +typedef FSERROR FAR *FSERRPTR; /* pointer to error array (in FAR storage!) */ + + +/* Private subobject */ + +#define MAX_Q_COMPS 4 /* max components I can handle */ + +typedef struct { + struct jpeg_color_quantizer pub; /* public fields */ + + /* Initially allocated colormap is saved here */ + JSAMPARRAY sv_colormap; /* The color map as a 2-D pixel array */ + int sv_actual; /* number of entries in use */ + + JSAMPARRAY colorindex; /* Precomputed mapping for speed */ + /* colorindex[i][j] = index of color closest to pixel value j in component i, + * premultiplied as described above. Since colormap indexes must fit into + * JSAMPLEs, the entries of this array will too. + */ + boolean is_padded; /* is the colorindex padded for odither? */ + + int Ncolors[MAX_Q_COMPS]; /* # of values alloced to each component */ + + /* Variables for ordered dithering */ + int row_index; /* cur row's vertical index in dither matrix */ + ODITHER_MATRIX_PTR odither[MAX_Q_COMPS]; /* one dither array per component */ + + /* Variables for Floyd-Steinberg dithering */ + FSERRPTR fserrors[MAX_Q_COMPS]; /* accumulated errors */ + boolean on_odd_row; /* flag to remember which row we are on */ +} my_cquantizer; + +typedef my_cquantizer * my_cquantize_ptr; + + +/* + * Policy-making subroutines for create_colormap and create_colorindex. + * These routines determine the colormap to be used. The rest of the module + * only assumes that the colormap is orthogonal. + * + * * select_ncolors decides how to divvy up the available colors + * among the components. + * * output_value defines the set of representative values for a component. + * * largest_input_value defines the mapping from input values to + * representative values for a component. + * Note that the latter two routines may impose different policies for + * different components, though this is not currently done. + */ + + +LOCAL(int) +select_ncolors (j_decompress_ptr cinfo, int Ncolors[]) +/* Determine allocation of desired colors to components, */ +/* and fill in Ncolors[] array to indicate choice. */ +/* Return value is total number of colors (product of Ncolors[] values). */ +{ + int nc = cinfo->out_color_components; /* number of color components */ + int max_colors = cinfo->desired_number_of_colors; + int total_colors, iroot, i, j; + boolean changed; + long temp; + static const int RGB_order[3] = { RGB_GREEN, RGB_RED, RGB_BLUE }; + + /* We can allocate at least the nc'th root of max_colors per component. */ + /* Compute floor(nc'th root of max_colors). */ + iroot = 1; + do { + iroot++; + temp = iroot; /* set temp = iroot ** nc */ + for (i = 1; i < nc; i++) + temp *= iroot; + } while (temp <= (long) max_colors); /* repeat till iroot exceeds root */ + iroot--; /* now iroot = floor(root) */ + + /* Must have at least 2 color values per component */ + if (iroot < 2) + ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, (int) temp); + + /* Initialize to iroot color values for each component */ + total_colors = 1; + for (i = 0; i < nc; i++) { + Ncolors[i] = iroot; + total_colors *= iroot; + } + /* We may be able to increment the count for one or more components without + * exceeding max_colors, though we know not all can be incremented. + * Sometimes, the first component can be incremented more than once! + * (Example: for 16 colors, we start at 2*2*2, go to 3*2*2, then 4*2*2.) + * In RGB colorspace, try to increment G first, then R, then B. + */ + do { + changed = FALSE; + for (i = 0; i < nc; i++) { + j = (cinfo->out_color_space == JCS_RGB ? RGB_order[i] : i); + /* calculate new total_colors if Ncolors[j] is incremented */ + temp = total_colors / Ncolors[j]; + temp *= Ncolors[j]+1; /* done in long arith to avoid oflo */ + if (temp > (long) max_colors) + break; /* won't fit, done with this pass */ + Ncolors[j]++; /* OK, apply the increment */ + total_colors = (int) temp; + changed = TRUE; + } + } while (changed); + + return total_colors; +} + + +LOCAL(int) +output_value (j_decompress_ptr cinfo, int ci, int j, int maxj) +/* Return j'th output value, where j will range from 0 to maxj */ +/* The output values must fall in 0..MAXJSAMPLE in increasing order */ +{ + (void)cinfo;(void)ci; + /* We always provide values 0 and MAXJSAMPLE for each component; + * any additional values are equally spaced between these limits. + * (Forcing the upper and lower values to the limits ensures that + * dithering can't produce a color outside the selected gamut.) + */ + return (int) (((INT32) j * MAXJSAMPLE + maxj/2) / maxj); +} + + +LOCAL(int) +largest_input_value (j_decompress_ptr cinfo, int ci, int j, int maxj) +/* Return largest input value that should map to j'th output value */ +/* Must have largest(j=0) >= 0, and largest(j=maxj) >= MAXJSAMPLE */ +{ + (void)cinfo;(void)ci; + /* Breakpoints are halfway between values returned by output_value */ + return (int) (((INT32) (2*j + 1) * MAXJSAMPLE + maxj) / (2*maxj)); +} + + +/* + * Create the colormap. + */ + +LOCAL(void) +create_colormap (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + JSAMPARRAY colormap; /* Created colormap */ + int total_colors; /* Number of distinct output colors */ + int i,j,k, nci, blksize, blkdist, ptr, val; + + /* Select number of colors for each component */ + total_colors = select_ncolors(cinfo, cquantize->Ncolors); + + /* Report selected color counts */ + if (cinfo->out_color_components == 3) + TRACEMS4(cinfo, 1, JTRC_QUANT_3_NCOLORS, + total_colors, cquantize->Ncolors[0], + cquantize->Ncolors[1], cquantize->Ncolors[2]); + else + TRACEMS1(cinfo, 1, JTRC_QUANT_NCOLORS, total_colors); + + /* Allocate and fill in the colormap. */ + /* The colors are ordered in the map in standard row-major order, */ + /* i.e. rightmost (highest-indexed) color changes most rapidly. */ + + colormap = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) total_colors, (JDIMENSION) cinfo->out_color_components); + + /* blksize is number of adjacent repeated entries for a component */ + /* blkdist is distance between groups of identical entries for a component */ + blkdist = total_colors; + + for (i = 0; i < cinfo->out_color_components; i++) { + /* fill in colormap entries for i'th color component */ + nci = cquantize->Ncolors[i]; /* # of distinct values for this color */ + blksize = blkdist / nci; + for (j = 0; j < nci; j++) { + /* Compute j'th output value (out of nci) for component */ + val = output_value(cinfo, i, j, nci-1); + /* Fill in all colormap entries that have this value of this component */ + for (ptr = j * blksize; ptr < total_colors; ptr += blkdist) { + /* fill in blksize entries beginning at ptr */ + for (k = 0; k < blksize; k++) + colormap[i][ptr+k] = (JSAMPLE) val; + } + } + blkdist = blksize; /* blksize of this color is blkdist of next */ + } + + /* Save the colormap in private storage, + * where it will survive color quantization mode changes. + */ + cquantize->sv_colormap = colormap; + cquantize->sv_actual = total_colors; +} + + +/* + * Create the color index table. + */ + +LOCAL(void) +create_colorindex (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + JSAMPROW indexptr; + int i,j,k, nci, blksize, val, pad; + + /* For ordered dither, we pad the color index tables by MAXJSAMPLE in + * each direction (input index values can be -MAXJSAMPLE .. 2*MAXJSAMPLE). + * This is not necessary in the other dithering modes. However, we + * flag whether it was done in case user changes dithering mode. + */ + if (cinfo->dither_mode == JDITHER_ORDERED) { + pad = MAXJSAMPLE*2; + cquantize->is_padded = TRUE; + } else { + pad = 0; + cquantize->is_padded = FALSE; + } + + cquantize->colorindex = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) (MAXJSAMPLE+1 + pad), + (JDIMENSION) cinfo->out_color_components); + + /* blksize is number of adjacent repeated entries for a component */ + blksize = cquantize->sv_actual; + + for (i = 0; i < cinfo->out_color_components; i++) { + /* fill in colorindex entries for i'th color component */ + nci = cquantize->Ncolors[i]; /* # of distinct values for this color */ + blksize = blksize / nci; + + /* adjust colorindex pointers to provide padding at negative indexes. */ + if (pad) + cquantize->colorindex[i] += MAXJSAMPLE; + + /* in loop, val = index of current output value, */ + /* and k = largest j that maps to current val */ + indexptr = cquantize->colorindex[i]; + val = 0; + k = largest_input_value(cinfo, i, 0, nci-1); + for (j = 0; j <= MAXJSAMPLE; j++) { + while (j > k) /* advance val if past boundary */ + k = largest_input_value(cinfo, i, ++val, nci-1); + /* premultiply so that no multiplication needed in main processing */ + indexptr[j] = (JSAMPLE) (val * blksize); + } + /* Pad at both ends if necessary */ + if (pad) + for (j = 1; j <= MAXJSAMPLE; j++) { + indexptr[-j] = indexptr[0]; + indexptr[MAXJSAMPLE+j] = indexptr[MAXJSAMPLE]; + } + } +} + + +/* + * Create an ordered-dither array for a component having ncolors + * distinct output values. + */ + +LOCAL(ODITHER_MATRIX_PTR) +make_odither_array (j_decompress_ptr cinfo, int ncolors) +{ + ODITHER_MATRIX_PTR odither; + int j,k; + INT32 num,den; + + odither = (ODITHER_MATRIX_PTR) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(ODITHER_MATRIX)); + /* The inter-value distance for this color is MAXJSAMPLE/(ncolors-1). + * Hence the dither value for the matrix cell with fill order f + * (f=0..N-1) should be (N-1-2*f)/(2*N) * MAXJSAMPLE/(ncolors-1). + * On 16-bit-int machine, be careful to avoid overflow. + */ + den = 2 * ODITHER_CELLS * ((INT32) (ncolors - 1)); + for (j = 0; j < ODITHER_SIZE; j++) { + for (k = 0; k < ODITHER_SIZE; k++) { + num = ((INT32) (ODITHER_CELLS-1 - 2*((int)base_dither_matrix[j][k]))) + * MAXJSAMPLE; + /* Ensure round towards zero despite C's lack of consistency + * about rounding negative values in integer division... + */ + odither[j][k] = (int) (num<0 ? -((-num)/den) : num/den); + } + } + return odither; +} + + +/* + * Create the ordered-dither tables. + * Components having the same number of representative colors may + * share a dither table. + */ + +LOCAL(void) +create_odither_tables (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + ODITHER_MATRIX_PTR odither; + int i, j, nci; + + for (i = 0; i < cinfo->out_color_components; i++) { + nci = cquantize->Ncolors[i]; /* # of distinct values for this color */ + odither = NULL; /* search for matching prior component */ + for (j = 0; j < i; j++) { + if (nci == cquantize->Ncolors[j]) { + odither = cquantize->odither[j]; + break; + } + } + if (odither == NULL) /* need a new table? */ + odither = make_odither_array(cinfo, nci); + cquantize->odither[i] = odither; + } +} + + +/* + * Map some rows of pixels to the output colormapped representation. + */ + +METHODDEF(void) +color_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf, + JSAMPARRAY output_buf, int num_rows) +/* General case, no dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + JSAMPARRAY colorindex = cquantize->colorindex; + register int pixcode, ci; + register JSAMPROW ptrin, ptrout; + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + register int nc = cinfo->out_color_components; + + for (row = 0; row < num_rows; row++) { + ptrin = input_buf[row]; + ptrout = output_buf[row]; + for (col = width; col > 0; col--) { + pixcode = 0; + for (ci = 0; ci < nc; ci++) { + pixcode += GETJSAMPLE(colorindex[ci][GETJSAMPLE(*ptrin++)]); + } + *ptrout++ = (JSAMPLE) pixcode; + } + } +} + + +METHODDEF(void) +color_quantize3 (j_decompress_ptr cinfo, JSAMPARRAY input_buf, + JSAMPARRAY output_buf, int num_rows) +/* Fast path for out_color_components==3, no dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + register int pixcode; + register JSAMPROW ptrin, ptrout; + JSAMPROW colorindex0 = cquantize->colorindex[0]; + JSAMPROW colorindex1 = cquantize->colorindex[1]; + JSAMPROW colorindex2 = cquantize->colorindex[2]; + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + + for (row = 0; row < num_rows; row++) { + ptrin = input_buf[row]; + ptrout = output_buf[row]; + for (col = width; col > 0; col--) { + pixcode = GETJSAMPLE(colorindex0[GETJSAMPLE(*ptrin++)]); + pixcode += GETJSAMPLE(colorindex1[GETJSAMPLE(*ptrin++)]); + pixcode += GETJSAMPLE(colorindex2[GETJSAMPLE(*ptrin++)]); + *ptrout++ = (JSAMPLE) pixcode; + } + } +} + + +METHODDEF(void) +quantize_ord_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf, + JSAMPARRAY output_buf, int num_rows) +/* General case, with ordered dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + register JSAMPROW input_ptr; + register JSAMPROW output_ptr; + JSAMPROW colorindex_ci; + int * dither; /* points to active row of dither matrix */ + int row_index, col_index; /* current indexes into dither matrix */ + int nc = cinfo->out_color_components; + int ci; + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + + for (row = 0; row < num_rows; row++) { + /* Initialize output values to 0 so can process components separately */ + jzero_far((void FAR *) output_buf[row], + (size_t) (width * SIZEOF(JSAMPLE))); + row_index = cquantize->row_index; + for (ci = 0; ci < nc; ci++) { + input_ptr = input_buf[row] + ci; + output_ptr = output_buf[row]; + colorindex_ci = cquantize->colorindex[ci]; + dither = cquantize->odither[ci][row_index]; + col_index = 0; + + for (col = width; col > 0; col--) { + /* Form pixel value + dither, range-limit to 0..MAXJSAMPLE, + * select output value, accumulate into output code for this pixel. + * Range-limiting need not be done explicitly, as we have extended + * the colorindex table to produce the right answers for out-of-range + * inputs. The maximum dither is +- MAXJSAMPLE; this sets the + * required amount of padding. + */ + *output_ptr += colorindex_ci[GETJSAMPLE(*input_ptr)+dither[col_index]]; + input_ptr += nc; + output_ptr++; + col_index = (col_index + 1) & ODITHER_MASK; + } + } + /* Advance row index for next row */ + row_index = (row_index + 1) & ODITHER_MASK; + cquantize->row_index = row_index; + } +} + + +METHODDEF(void) +quantize3_ord_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf, + JSAMPARRAY output_buf, int num_rows) +/* Fast path for out_color_components==3, with ordered dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + register int pixcode; + register JSAMPROW input_ptr; + register JSAMPROW output_ptr; + JSAMPROW colorindex0 = cquantize->colorindex[0]; + JSAMPROW colorindex1 = cquantize->colorindex[1]; + JSAMPROW colorindex2 = cquantize->colorindex[2]; + int * dither0; /* points to active row of dither matrix */ + int * dither1; + int * dither2; + int row_index, col_index; /* current indexes into dither matrix */ + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + + for (row = 0; row < num_rows; row++) { + row_index = cquantize->row_index; + input_ptr = input_buf[row]; + output_ptr = output_buf[row]; + dither0 = cquantize->odither[0][row_index]; + dither1 = cquantize->odither[1][row_index]; + dither2 = cquantize->odither[2][row_index]; + col_index = 0; + + for (col = width; col > 0; col--) { + pixcode = GETJSAMPLE(colorindex0[GETJSAMPLE(*input_ptr++) + + dither0[col_index]]); + pixcode += GETJSAMPLE(colorindex1[GETJSAMPLE(*input_ptr++) + + dither1[col_index]]); + pixcode += GETJSAMPLE(colorindex2[GETJSAMPLE(*input_ptr++) + + dither2[col_index]]); + *output_ptr++ = (JSAMPLE) pixcode; + col_index = (col_index + 1) & ODITHER_MASK; + } + row_index = (row_index + 1) & ODITHER_MASK; + cquantize->row_index = row_index; + } +} + + +METHODDEF(void) +quantize_fs_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf, + JSAMPARRAY output_buf, int num_rows) +/* General case, with Floyd-Steinberg dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + register LOCFSERROR cur; /* current error or pixel value */ + LOCFSERROR belowerr; /* error for pixel below cur */ + LOCFSERROR bpreverr; /* error for below/prev col */ + LOCFSERROR bnexterr; /* error for below/next col */ + LOCFSERROR delta; + register FSERRPTR errorptr; /* => fserrors[] at column before current */ + register JSAMPROW input_ptr; + register JSAMPROW output_ptr; + JSAMPROW colorindex_ci; + JSAMPROW colormap_ci; + int pixcode; + int nc = cinfo->out_color_components; + int dir; /* 1 for left-to-right, -1 for right-to-left */ + int dirnc; /* dir * nc */ + int ci; + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + JSAMPLE *range_limit = cinfo->sample_range_limit; + SHIFT_TEMPS + + for (row = 0; row < num_rows; row++) { + /* Initialize output values to 0 so can process components separately */ + jzero_far((void FAR *) output_buf[row], + (size_t) (width * SIZEOF(JSAMPLE))); + for (ci = 0; ci < nc; ci++) { + input_ptr = input_buf[row] + ci; + output_ptr = output_buf[row]; + if (cquantize->on_odd_row) { + /* work right to left in this row */ + input_ptr += (width-1) * nc; /* so point to rightmost pixel */ + output_ptr += width-1; + dir = -1; + dirnc = -nc; + errorptr = cquantize->fserrors[ci] + (width+1); /* => entry after last column */ + } else { + /* work left to right in this row */ + dir = 1; + dirnc = nc; + errorptr = cquantize->fserrors[ci]; /* => entry before first column */ + } + colorindex_ci = cquantize->colorindex[ci]; + colormap_ci = cquantize->sv_colormap[ci]; + /* Preset error values: no error propagated to first pixel from left */ + cur = 0; + /* and no error propagated to row below yet */ + belowerr = bpreverr = 0; + + for (col = width; col > 0; col--) { + /* cur holds the error propagated from the previous pixel on the + * current line. Add the error propagated from the previous line + * to form the complete error correction term for this pixel, and + * round the error term (which is expressed * 16) to an integer. + * RIGHT_SHIFT rounds towards minus infinity, so adding 8 is correct + * for either sign of the error value. + * Note: errorptr points to *previous* column's array entry. + */ + cur = RIGHT_SHIFT(cur + errorptr[dir] + 8, 4); + /* Form pixel value + error, and range-limit to 0..MAXJSAMPLE. + * The maximum error is +- MAXJSAMPLE; this sets the required size + * of the range_limit array. + */ + cur += GETJSAMPLE(*input_ptr); + cur = GETJSAMPLE(range_limit[cur]); + /* Select output value, accumulate into output code for this pixel */ + pixcode = GETJSAMPLE(colorindex_ci[cur]); + *output_ptr += (JSAMPLE) pixcode; + /* Compute actual representation error at this pixel */ + /* Note: we can do this even though we don't have the final */ + /* pixel code, because the colormap is orthogonal. */ + cur -= GETJSAMPLE(colormap_ci[pixcode]); + /* Compute error fractions to be propagated to adjacent pixels. + * Add these into the running sums, and simultaneously shift the + * next-line error sums left by 1 column. + */ + bnexterr = cur; + delta = cur * 2; + cur += delta; /* form error * 3 */ + errorptr[0] = (FSERROR) (bpreverr + cur); + cur += delta; /* form error * 5 */ + bpreverr = belowerr + cur; + belowerr = bnexterr; + cur += delta; /* form error * 7 */ + /* At this point cur contains the 7/16 error value to be propagated + * to the next pixel on the current line, and all the errors for the + * next line have been shifted over. We are therefore ready to move on. + */ + input_ptr += dirnc; /* advance input ptr to next column */ + output_ptr += dir; /* advance output ptr to next column */ + errorptr += dir; /* advance errorptr to current column */ + } + /* Post-loop cleanup: we must unload the final error value into the + * final fserrors[] entry. Note we need not unload belowerr because + * it is for the dummy column before or after the actual array. + */ + errorptr[0] = (FSERROR) bpreverr; /* unload prev err into array */ + } + cquantize->on_odd_row = (cquantize->on_odd_row ? FALSE : TRUE); + } +} + + +/* + * Allocate workspace for Floyd-Steinberg errors. + */ + +LOCAL(void) +alloc_fs_workspace (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + size_t arraysize; + int i; + + arraysize = (size_t) ((cinfo->output_width + 2) * SIZEOF(FSERROR)); + for (i = 0; i < cinfo->out_color_components; i++) { + cquantize->fserrors[i] = (FSERRPTR) + (*cinfo->mem->alloc_large)((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize); + } +} + + +/* + * Initialize for one-pass color quantization. + */ + +METHODDEF(void) +start_pass_1_quant (j_decompress_ptr cinfo, boolean is_pre_scan) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + size_t arraysize; + int i; + (void)is_pre_scan; + + /* Install my colormap. */ + cinfo->colormap = cquantize->sv_colormap; + cinfo->actual_number_of_colors = cquantize->sv_actual; + + /* Initialize for desired dithering mode. */ + switch (cinfo->dither_mode) { + case JDITHER_NONE: + if (cinfo->out_color_components == 3) + cquantize->pub.color_quantize = color_quantize3; + else + cquantize->pub.color_quantize = color_quantize; + break; + case JDITHER_ORDERED: + if (cinfo->out_color_components == 3) + cquantize->pub.color_quantize = quantize3_ord_dither; + else + cquantize->pub.color_quantize = quantize_ord_dither; + cquantize->row_index = 0; /* initialize state for ordered dither */ + /* If user changed to ordered dither from another mode, + * we must recreate the color index table with padding. + * This will cost extra space, but probably isn't very likely. + */ + if (! cquantize->is_padded) + create_colorindex(cinfo); + /* Create ordered-dither tables if we didn't already. */ + if (cquantize->odither[0] == NULL) + create_odither_tables(cinfo); + break; + case JDITHER_FS: + cquantize->pub.color_quantize = quantize_fs_dither; + cquantize->on_odd_row = FALSE; /* initialize state for F-S dither */ + /* Allocate Floyd-Steinberg workspace if didn't already. */ + if (cquantize->fserrors[0] == NULL) + alloc_fs_workspace(cinfo); + /* Initialize the propagated errors to zero. */ + arraysize = (size_t) ((cinfo->output_width + 2) * SIZEOF(FSERROR)); + for (i = 0; i < cinfo->out_color_components; i++) + jzero_far((void FAR *) cquantize->fserrors[i], arraysize); + break; + default: + ERREXIT(cinfo, JERR_NOT_COMPILED); + break; + } +} + + +/* + * Finish up at the end of the pass. + */ + +METHODDEF(void) +finish_pass_1_quant (j_decompress_ptr cinfo) +{ + (void)cinfo; + /* no work in 1-pass case */ +} + + +/* + * Switch to a new external colormap between output passes. + * Shouldn't get to this module! + */ + +METHODDEF(void) +new_color_map_1_quant (j_decompress_ptr cinfo) +{ + ERREXIT(cinfo, JERR_MODE_CHANGE); +} + + +/* + * Module initialization routine for 1-pass color quantization. + */ + +GLOBAL(void) +jinit_1pass_quantizer (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize; + + cquantize = (my_cquantize_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_cquantizer)); + cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize; + cquantize->pub.start_pass = start_pass_1_quant; + cquantize->pub.finish_pass = finish_pass_1_quant; + cquantize->pub.new_color_map = new_color_map_1_quant; + cquantize->fserrors[0] = NULL; /* Flag FS workspace not allocated */ + cquantize->odither[0] = NULL; /* Also flag odither arrays not allocated */ + + /* Make sure my internal arrays won't overflow */ + if (cinfo->out_color_components > MAX_Q_COMPS) + ERREXIT1(cinfo, JERR_QUANT_COMPONENTS, MAX_Q_COMPS); + /* Make sure colormap indexes can be represented by JSAMPLEs */ + if (cinfo->desired_number_of_colors > (MAXJSAMPLE+1)) + ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXJSAMPLE+1); + + /* Create the colormap and color index table. */ + create_colormap(cinfo); + create_colorindex(cinfo); + + /* Allocate Floyd-Steinberg workspace now if requested. + * We do this now since it is FAR storage and may affect the memory + * manager's space calculations. If the user changes to FS dither + * mode in a later pass, we will allocate the space then, and will + * possibly overrun the max_memory_to_use setting. + */ + if (cinfo->dither_mode == JDITHER_FS) + alloc_fs_workspace(cinfo); +} + +#endif /* QUANT_1PASS_SUPPORTED */ diff --git a/src/gdcmjpeg/jquant2.c b/src/gdcmjpeg/jquant2.c new file mode 100644 index 00000000..9f9f7091 --- /dev/null +++ b/src/gdcmjpeg/jquant2.c @@ -0,0 +1,1312 @@ +/* + * jquant2.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains 2-pass color quantization (color mapping) routines. + * These routines provide selection of a custom color map for an image, + * followed by mapping of the image to that color map, with optional + * Floyd-Steinberg dithering. + * It is also possible to use just the second pass to map to an arbitrary + * externally-given color map. + * + * Note: ordered dithering is not supported, since there isn't any fast + * way to compute intercolor distances; it's unclear that ordered dither's + * fundamental assumptions even hold with an irregularly spaced color map. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + +#ifdef QUANT_2PASS_SUPPORTED + + +/* + * This module implements the well-known Heckbert paradigm for color + * quantization. Most of the ideas used here can be traced back to + * Heckbert's seminal paper + * Heckbert, Paul. "Color Image Quantization for Frame Buffer Display", + * Proc. SIGGRAPH '82, Computer Graphics v.16 #3 (July 1982), pp 297-304. + * + * In the first pass over the image, we accumulate a histogram showing the + * usage count of each possible color. To keep the histogram to a reasonable + * size, we reduce the precision of the input; typical practice is to retain + * 5 or 6 bits per color, so that 8 or 4 different input values are counted + * in the same histogram cell. + * + * Next, the color-selection step begins with a box representing the whole + * color space, and repeatedly splits the "largest" remaining box until we + * have as many boxes as desired colors. Then the mean color in each + * remaining box becomes one of the possible output colors. + * + * The second pass over the image maps each input pixel to the closest output + * color (optionally after applying a Floyd-Steinberg dithering correction). + * This mapping is logically trivial, but making it go fast enough requires + * considerable care. + * + * Heckbert-style quantizers vary a good deal in their policies for choosing + * the "largest" box and deciding where to cut it. The particular policies + * used here have proved out well in experimental comparisons, but better ones + * may yet be found. + * + * In earlier versions of the IJG code, this module quantized in YCbCr color + * space, processing the raw upsampled data without a color conversion step. + * This allowed the color conversion math to be done only once per colormap + * entry, not once per pixel. However, that optimization precluded other + * useful optimizations (such as merging color conversion with upsampling) + * and it also interfered with desired capabilities such as quantizing to an + * externally-supplied colormap. We have therefore abandoned that approach. + * The present code works in the post-conversion color space, typically RGB. + * + * To improve the visual quality of the results, we actually work in scaled + * RGB space, giving G distances more weight than R, and R in turn more than + * B. To do everything in integer math, we must use integer scale factors. + * The 2/3/1 scale factors used here correspond loosely to the relative + * weights of the colors in the NTSC grayscale equation. + * If you want to use this code to quantize a non-RGB color space, you'll + * probably need to change these scale factors. + */ + +#define R_SCALE 2 /* scale R distances by this much */ +#define G_SCALE 3 /* scale G distances by this much */ +#define B_SCALE 1 /* and B by this much */ + +/* Relabel R/G/B as components 0/1/2, respecting the RGB ordering defined + * in jmorecfg.h. As the code stands, it will do the right thing for R,G,B + * and B,G,R orders. If you define some other weird order in jmorecfg.h, + * you'll get compile errors until you extend this logic. In that case + * you'll probably want to tweak the histogram sizes too. + */ + +#if RGB_RED == 0 +#define C0_SCALE R_SCALE +#endif +#if RGB_BLUE == 0 +#define C0_SCALE B_SCALE +#endif +#if RGB_GREEN == 1 +#define C1_SCALE G_SCALE +#endif +#if RGB_RED == 2 +#define C2_SCALE R_SCALE +#endif +#if RGB_BLUE == 2 +#define C2_SCALE B_SCALE +#endif + + +/* + * First we have the histogram data structure and routines for creating it. + * + * The number of bits of precision can be adjusted by changing these symbols. + * We recommend keeping 6 bits for G and 5 each for R and B. + * If you have plenty of memory and cycles, 6 bits all around gives marginally + * better results; if you are short of memory, 5 bits all around will save + * some space but degrade the results. + * To maintain a fully accurate histogram, we'd need to allocate a "long" + * (preferably unsigned long) for each cell. In practice this is overkill; + * we can get by with 16 bits per cell. Few of the cell counts will overflow, + * and clamping those that do overflow to the maximum value will give close- + * enough results. This reduces the recommended histogram size from 256Kb + * to 128Kb, which is a useful savings on PC-class machines. + * (In the second pass the histogram space is re-used for pixel mapping data; + * in that capacity, each cell must be able to store zero to the number of + * desired colors. 16 bits/cell is plenty for that too.) + * Since the JPEG code is intended to run in small memory model on 80x86 + * machines, we can't just allocate the histogram in one chunk. Instead + * of a true 3-D array, we use a row of pointers to 2-D arrays. Each + * pointer corresponds to a C0 value (typically 2^5 = 32 pointers) and + * each 2-D array has 2^6*2^5 = 2048 or 2^6*2^6 = 4096 entries. Note that + * on 80x86 machines, the pointer row is in near memory but the actual + * arrays are in far memory (same arrangement as we use for image arrays). + */ + +#define MAXNUMCOLORS (MAXJSAMPLE+1) /* maximum size of colormap */ + +/* These will do the right thing for either R,G,B or B,G,R color order, + * but you may not like the results for other color orders. + */ +#define HIST_C0_BITS 5 /* bits of precision in R/B histogram */ +#define HIST_C1_BITS 6 /* bits of precision in G histogram */ +#define HIST_C2_BITS 5 /* bits of precision in B/R histogram */ + +/* Number of elements along histogram axes. */ +#define HIST_C0_ELEMS (1<cquantize; + register JSAMPROW ptr; + register histptr histp; + register hist3d histogram = cquantize->histogram; + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + (void)output_buf; + + for (row = 0; row < num_rows; row++) { + ptr = input_buf[row]; + for (col = width; col > 0; col--) { + /* get pixel value and index into the histogram */ + histp = & histogram[GETJSAMPLE(ptr[0]) >> C0_SHIFT] + [GETJSAMPLE(ptr[1]) >> C1_SHIFT] + [GETJSAMPLE(ptr[2]) >> C2_SHIFT]; + /* increment, check for overflow and undo increment if so. */ + if (++(*histp) <= 0) + (*histp)--; + ptr += 3; + } + } +} + + +/* + * Next we have the really interesting routines: selection of a colormap + * given the completed histogram. + * These routines work with a list of "boxes", each representing a rectangular + * subset of the input color space (to histogram precision). + */ + +typedef struct { + /* The bounds of the box (inclusive); expressed as histogram indexes */ + int c0min, c0max; + int c1min, c1max; + int c2min, c2max; + /* The volume (actually 2-norm) of the box */ + INT32 volume; + /* The number of nonzero histogram cells within this box */ + long colorcount; +} box; + +typedef box * boxptr; + + +LOCAL(boxptr) +find_biggest_color_pop (boxptr boxlist, int numboxes) +/* Find the splittable box with the largest color population */ +/* Returns NULL if no splittable boxes remain */ +{ + register boxptr boxp; + register int i; + register long maxc = 0; + boxptr which = NULL; + + for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) { + if (boxp->colorcount > maxc && boxp->volume > 0) { + which = boxp; + maxc = boxp->colorcount; + } + } + return which; +} + + +LOCAL(boxptr) +find_biggest_volume (boxptr boxlist, int numboxes) +/* Find the splittable box with the largest (scaled) volume */ +/* Returns NULL if no splittable boxes remain */ +{ + register boxptr boxp; + register int i; + register INT32 maxv = 0; + boxptr which = NULL; + + for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) { + if (boxp->volume > maxv) { + which = boxp; + maxv = boxp->volume; + } + } + return which; +} + + +LOCAL(void) +update_box (j_decompress_ptr cinfo, boxptr boxp) +/* Shrink the min/max bounds of a box to enclose only nonzero elements, */ +/* and recompute its volume and population */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + hist3d histogram = cquantize->histogram; + histptr histp; + int c0,c1,c2; + int c0min,c0max,c1min,c1max,c2min,c2max; + INT32 dist0,dist1,dist2; + long ccount; + + c0min = boxp->c0min; c0max = boxp->c0max; + c1min = boxp->c1min; c1max = boxp->c1max; + c2min = boxp->c2min; c2max = boxp->c2max; + + if (c0max > c0min) + for (c0 = c0min; c0 <= c0max; c0++) + for (c1 = c1min; c1 <= c1max; c1++) { + histp = & histogram[c0][c1][c2min]; + for (c2 = c2min; c2 <= c2max; c2++) + if (*histp++ != 0) { + boxp->c0min = c0min = c0; + goto have_c0min; + } + } + have_c0min: + if (c0max > c0min) + for (c0 = c0max; c0 >= c0min; c0--) + for (c1 = c1min; c1 <= c1max; c1++) { + histp = & histogram[c0][c1][c2min]; + for (c2 = c2min; c2 <= c2max; c2++) + if (*histp++ != 0) { + boxp->c0max = c0max = c0; + goto have_c0max; + } + } + have_c0max: + if (c1max > c1min) + for (c1 = c1min; c1 <= c1max; c1++) + for (c0 = c0min; c0 <= c0max; c0++) { + histp = & histogram[c0][c1][c2min]; + for (c2 = c2min; c2 <= c2max; c2++) + if (*histp++ != 0) { + boxp->c1min = c1min = c1; + goto have_c1min; + } + } + have_c1min: + if (c1max > c1min) + for (c1 = c1max; c1 >= c1min; c1--) + for (c0 = c0min; c0 <= c0max; c0++) { + histp = & histogram[c0][c1][c2min]; + for (c2 = c2min; c2 <= c2max; c2++) + if (*histp++ != 0) { + boxp->c1max = c1max = c1; + goto have_c1max; + } + } + have_c1max: + if (c2max > c2min) + for (c2 = c2min; c2 <= c2max; c2++) + for (c0 = c0min; c0 <= c0max; c0++) { + histp = & histogram[c0][c1min][c2]; + for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS) + if (*histp != 0) { + boxp->c2min = c2min = c2; + goto have_c2min; + } + } + have_c2min: + if (c2max > c2min) + for (c2 = c2max; c2 >= c2min; c2--) + for (c0 = c0min; c0 <= c0max; c0++) { + histp = & histogram[c0][c1min][c2]; + for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS) + if (*histp != 0) { + boxp->c2max = c2max = c2; + goto have_c2max; + } + } + have_c2max: + + /* Update box volume. + * We use 2-norm rather than real volume here; this biases the method + * against making long narrow boxes, and it has the side benefit that + * a box is splittable iff norm > 0. + * Since the differences are expressed in histogram-cell units, + * we have to shift back to JSAMPLE units to get consistent distances; + * after which, we scale according to the selected distance scale factors. + */ + dist0 = ((c0max - c0min) << C0_SHIFT) * C0_SCALE; + dist1 = ((c1max - c1min) << C1_SHIFT) * C1_SCALE; + dist2 = ((c2max - c2min) << C2_SHIFT) * C2_SCALE; + boxp->volume = dist0*dist0 + dist1*dist1 + dist2*dist2; + + /* Now scan remaining volume of box and compute population */ + ccount = 0; + for (c0 = c0min; c0 <= c0max; c0++) + for (c1 = c1min; c1 <= c1max; c1++) { + histp = & histogram[c0][c1][c2min]; + for (c2 = c2min; c2 <= c2max; c2++, histp++) + if (*histp != 0) { + ccount++; + } + } + boxp->colorcount = ccount; +} + + +LOCAL(int) +median_cut (j_decompress_ptr cinfo, boxptr boxlist, int numboxes, + int desired_colors) +/* Repeatedly select and split the largest box until we have enough boxes */ +{ + int n,lb; + int c0,c1,c2,cmax; + register boxptr b1,b2; + + while (numboxes < desired_colors) { + /* Select box to split. + * Current algorithm: by population for first half, then by volume. + */ + if (numboxes*2 <= desired_colors) { + b1 = find_biggest_color_pop(boxlist, numboxes); + } else { + b1 = find_biggest_volume(boxlist, numboxes); + } + if (b1 == NULL) /* no splittable boxes left! */ + break; + b2 = &boxlist[numboxes]; /* where new box will go */ + /* Copy the color bounds to the new box. */ + b2->c0max = b1->c0max; b2->c1max = b1->c1max; b2->c2max = b1->c2max; + b2->c0min = b1->c0min; b2->c1min = b1->c1min; b2->c2min = b1->c2min; + /* Choose which axis to split the box on. + * Current algorithm: longest scaled axis. + * See notes in update_box about scaling distances. + */ + c0 = ((b1->c0max - b1->c0min) << C0_SHIFT) * C0_SCALE; + c1 = ((b1->c1max - b1->c1min) << C1_SHIFT) * C1_SCALE; + c2 = ((b1->c2max - b1->c2min) << C2_SHIFT) * C2_SCALE; + /* We want to break any ties in favor of green, then red, blue last. + * This code does the right thing for R,G,B or B,G,R color orders only. + */ +#if RGB_RED == 0 + cmax = c1; n = 1; + if (c0 > cmax) { cmax = c0; n = 0; } + if (c2 > cmax) { n = 2; } +#else + cmax = c1; n = 1; + if (c2 > cmax) { cmax = c2; n = 2; } + if (c0 > cmax) { n = 0; } +#endif + /* Choose split point along selected axis, and update box bounds. + * Current algorithm: split at halfway point. + * (Since the box has been shrunk to minimum volume, + * any split will produce two nonempty subboxes.) + * Note that lb value is max for lower box, so must be < old max. + */ + switch (n) { + case 0: + lb = (b1->c0max + b1->c0min) / 2; + b1->c0max = lb; + b2->c0min = lb+1; + break; + case 1: + lb = (b1->c1max + b1->c1min) / 2; + b1->c1max = lb; + b2->c1min = lb+1; + break; + case 2: + lb = (b1->c2max + b1->c2min) / 2; + b1->c2max = lb; + b2->c2min = lb+1; + break; + } + /* Update stats for boxes */ + update_box(cinfo, b1); + update_box(cinfo, b2); + numboxes++; + } + return numboxes; +} + + +LOCAL(void) +compute_color (j_decompress_ptr cinfo, boxptr boxp, int icolor) +/* Compute representative color for a box, put it in colormap[icolor] */ +{ + /* Current algorithm: mean weighted by pixels (not colors) */ + /* Note it is important to get the rounding correct! */ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + hist3d histogram = cquantize->histogram; + histptr histp; + int c0,c1,c2; + int c0min,c0max,c1min,c1max,c2min,c2max; + long count; + long total = 0; + long c0total = 0; + long c1total = 0; + long c2total = 0; + + c0min = boxp->c0min; c0max = boxp->c0max; + c1min = boxp->c1min; c1max = boxp->c1max; + c2min = boxp->c2min; c2max = boxp->c2max; + + for (c0 = c0min; c0 <= c0max; c0++) + for (c1 = c1min; c1 <= c1max; c1++) { + histp = & histogram[c0][c1][c2min]; + for (c2 = c2min; c2 <= c2max; c2++) { + if ((count = *histp++) != 0) { + total += count; + c0total += ((c0 << C0_SHIFT) + ((1<>1)) * count; + c1total += ((c1 << C1_SHIFT) + ((1<>1)) * count; + c2total += ((c2 << C2_SHIFT) + ((1<>1)) * count; + } + } + } + + cinfo->colormap[0][icolor] = (JSAMPLE) ((c0total + (total>>1)) / total); + cinfo->colormap[1][icolor] = (JSAMPLE) ((c1total + (total>>1)) / total); + cinfo->colormap[2][icolor] = (JSAMPLE) ((c2total + (total>>1)) / total); +} + + +LOCAL(void) +select_colors (j_decompress_ptr cinfo, int desired_colors) +/* Master routine for color selection */ +{ + boxptr boxlist; + int numboxes; + int i; + + /* Allocate workspace for box list */ + boxlist = (boxptr) (*cinfo->mem->alloc_small) + ((j_common_ptr) cinfo, JPOOL_IMAGE, desired_colors * SIZEOF(box)); + /* Initialize one box containing whole space */ + numboxes = 1; + boxlist[0].c0min = 0; + boxlist[0].c0max = MAXJSAMPLE >> C0_SHIFT; + boxlist[0].c1min = 0; + boxlist[0].c1max = MAXJSAMPLE >> C1_SHIFT; + boxlist[0].c2min = 0; + boxlist[0].c2max = MAXJSAMPLE >> C2_SHIFT; + /* Shrink it to actually-used volume and set its statistics */ + update_box(cinfo, & boxlist[0]); + /* Perform median-cut to produce final box list */ + numboxes = median_cut(cinfo, boxlist, numboxes, desired_colors); + /* Compute the representative color for each box, fill colormap */ + for (i = 0; i < numboxes; i++) + compute_color(cinfo, & boxlist[i], i); + cinfo->actual_number_of_colors = numboxes; + TRACEMS1(cinfo, 1, JTRC_QUANT_SELECTED, numboxes); +} + + +/* + * These routines are concerned with the time-critical task of mapping input + * colors to the nearest color in the selected colormap. + * + * We re-use the histogram space as an "inverse color map", essentially a + * cache for the results of nearest-color searches. All colors within a + * histogram cell will be mapped to the same colormap entry, namely the one + * closest to the cell's center. This may not be quite the closest entry to + * the actual input color, but it's almost as good. A zero in the cache + * indicates we haven't found the nearest color for that cell yet; the array + * is cleared to zeroes before starting the mapping pass. When we find the + * nearest color for a cell, its colormap index plus one is recorded in the + * cache for future use. The pass2 scanning routines call fill_inverse_cmap + * when they need to use an unfilled entry in the cache. + * + * Our method of efficiently finding nearest colors is based on the "locally + * sorted search" idea described by Heckbert and on the incremental distance + * calculation described by Spencer W. Thomas in chapter III.1 of Graphics + * Gems II (James Arvo, ed. Academic Press, 1991). Thomas points out that + * the distances from a given colormap entry to each cell of the histogram can + * be computed quickly using an incremental method: the differences between + * distances to adjacent cells themselves differ by a constant. This allows a + * fairly fast implementation of the "brute force" approach of computing the + * distance from every colormap entry to every histogram cell. Unfortunately, + * it needs a work array to hold the best-distance-so-far for each histogram + * cell (because the inner loop has to be over cells, not colormap entries). + * The work array elements have to be INT32s, so the work array would need + * 256Kb at our recommended precision. This is not feasible in DOS machines. + * + * To get around these problems, we apply Thomas' method to compute the + * nearest colors for only the cells within a small subbox of the histogram. + * The work array need be only as big as the subbox, so the memory usage + * problem is solved. Furthermore, we need not fill subboxes that are never + * referenced in pass2; many images use only part of the color gamut, so a + * fair amount of work is saved. An additional advantage of this + * approach is that we can apply Heckbert's locality criterion to quickly + * eliminate colormap entries that are far away from the subbox; typically + * three-fourths of the colormap entries are rejected by Heckbert's criterion, + * and we need not compute their distances to individual cells in the subbox. + * The speed of this approach is heavily influenced by the subbox size: too + * small means too much overhead, too big loses because Heckbert's criterion + * can't eliminate as many colormap entries. Empirically the best subbox + * size seems to be about 1/512th of the histogram (1/8th in each direction). + * + * Thomas' article also describes a refined method which is asymptotically + * faster than the brute-force method, but it is also far more complex and + * cannot efficiently be applied to small subboxes. It is therefore not + * useful for programs intended to be portable to DOS machines. On machines + * with plenty of memory, filling the whole histogram in one shot with Thomas' + * refined method might be faster than the present code --- but then again, + * it might not be any faster, and it's certainly more complicated. + */ + + +/* log2(histogram cells in update box) for each axis; this can be adjusted */ +#define BOX_C0_LOG (HIST_C0_BITS-3) +#define BOX_C1_LOG (HIST_C1_BITS-3) +#define BOX_C2_LOG (HIST_C2_BITS-3) + +#define BOX_C0_ELEMS (1<actual_number_of_colors; + int maxc0, maxc1, maxc2; + int centerc0, centerc1, centerc2; + int i, x, ncolors; + INT32 minmaxdist, min_dist, max_dist, tdist; + INT32 mindist[MAXNUMCOLORS]; /* min distance to colormap entry i */ + + /* Compute true coordinates of update box's upper corner and center. + * Actually we compute the coordinates of the center of the upper-corner + * histogram cell, which are the upper bounds of the volume we care about. + * Note that since ">>" rounds down, the "center" values may be closer to + * min than to max; hence comparisons to them must be "<=", not "<". + */ + maxc0 = minc0 + ((1 << BOX_C0_SHIFT) - (1 << C0_SHIFT)); + centerc0 = (minc0 + maxc0) >> 1; + maxc1 = minc1 + ((1 << BOX_C1_SHIFT) - (1 << C1_SHIFT)); + centerc1 = (minc1 + maxc1) >> 1; + maxc2 = minc2 + ((1 << BOX_C2_SHIFT) - (1 << C2_SHIFT)); + centerc2 = (minc2 + maxc2) >> 1; + + /* For each color in colormap, find: + * 1. its minimum squared-distance to any point in the update box + * (zero if color is within update box); + * 2. its maximum squared-distance to any point in the update box. + * Both of these can be found by considering only the corners of the box. + * We save the minimum distance for each color in mindist[]; + * only the smallest maximum distance is of interest. + */ + minmaxdist = 0x7FFFFFFFL; + + for (i = 0; i < numcolors; i++) { + /* We compute the squared-c0-distance term, then add in the other two. */ + x = GETJSAMPLE(cinfo->colormap[0][i]); + if (x < minc0) { + tdist = (x - minc0) * C0_SCALE; + min_dist = tdist*tdist; + tdist = (x - maxc0) * C0_SCALE; + max_dist = tdist*tdist; + } else if (x > maxc0) { + tdist = (x - maxc0) * C0_SCALE; + min_dist = tdist*tdist; + tdist = (x - minc0) * C0_SCALE; + max_dist = tdist*tdist; + } else { + /* within cell range so no contribution to min_dist */ + min_dist = 0; + if (x <= centerc0) { + tdist = (x - maxc0) * C0_SCALE; + max_dist = tdist*tdist; + } else { + tdist = (x - minc0) * C0_SCALE; + max_dist = tdist*tdist; + } + } + + x = GETJSAMPLE(cinfo->colormap[1][i]); + if (x < minc1) { + tdist = (x - minc1) * C1_SCALE; + min_dist += tdist*tdist; + tdist = (x - maxc1) * C1_SCALE; + max_dist += tdist*tdist; + } else if (x > maxc1) { + tdist = (x - maxc1) * C1_SCALE; + min_dist += tdist*tdist; + tdist = (x - minc1) * C1_SCALE; + max_dist += tdist*tdist; + } else { + /* within cell range so no contribution to min_dist */ + if (x <= centerc1) { + tdist = (x - maxc1) * C1_SCALE; + max_dist += tdist*tdist; + } else { + tdist = (x - minc1) * C1_SCALE; + max_dist += tdist*tdist; + } + } + + x = GETJSAMPLE(cinfo->colormap[2][i]); + if (x < minc2) { + tdist = (x - minc2) * C2_SCALE; + min_dist += tdist*tdist; + tdist = (x - maxc2) * C2_SCALE; + max_dist += tdist*tdist; + } else if (x > maxc2) { + tdist = (x - maxc2) * C2_SCALE; + min_dist += tdist*tdist; + tdist = (x - minc2) * C2_SCALE; + max_dist += tdist*tdist; + } else { + /* within cell range so no contribution to min_dist */ + if (x <= centerc2) { + tdist = (x - maxc2) * C2_SCALE; + max_dist += tdist*tdist; + } else { + tdist = (x - minc2) * C2_SCALE; + max_dist += tdist*tdist; + } + } + + mindist[i] = min_dist; /* save away the results */ + if (max_dist < minmaxdist) + minmaxdist = max_dist; + } + + /* Now we know that no cell in the update box is more than minmaxdist + * away from some colormap entry. Therefore, only colors that are + * within minmaxdist of some part of the box need be considered. + */ + ncolors = 0; + for (i = 0; i < numcolors; i++) { + if (mindist[i] <= minmaxdist) + colorlist[ncolors++] = (JSAMPLE) i; + } + return ncolors; +} + + +LOCAL(void) +find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2, + int numcolors, JSAMPLE colorlist[], JSAMPLE bestcolor[]) +/* Find the closest colormap entry for each cell in the update box, + * given the list of candidate colors prepared by find_nearby_colors. + * Return the indexes of the closest entries in the bestcolor[] array. + * This routine uses Thomas' incremental distance calculation method to + * find the distance from a colormap entry to successive cells in the box. + */ +{ + int ic0, ic1, ic2; + int i, icolor; + register INT32 * bptr; /* pointer into bestdist[] array */ + JSAMPLE * cptr; /* pointer into bestcolor[] array */ + INT32 dist0, dist1; /* initial distance values */ + register INT32 dist2; /* current distance in inner loop */ + INT32 xx0, xx1; /* distance increments */ + register INT32 xx2; + INT32 inc0, inc1, inc2; /* initial values for increments */ + /* This array holds the distance to the nearest-so-far color for each cell */ + INT32 bestdist[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS]; + + /* Initialize best-distance for each cell of the update box */ + bptr = bestdist; + for (i = BOX_C0_ELEMS*BOX_C1_ELEMS*BOX_C2_ELEMS-1; i >= 0; i--) + *bptr++ = 0x7FFFFFFFL; + + /* For each color selected by find_nearby_colors, + * compute its distance to the center of each cell in the box. + * If that's less than best-so-far, update best distance and color number. + */ + + /* Nominal steps between cell centers ("x" in Thomas article) */ +#define STEP_C0 ((1 << C0_SHIFT) * C0_SCALE) +#define STEP_C1 ((1 << C1_SHIFT) * C1_SCALE) +#define STEP_C2 ((1 << C2_SHIFT) * C2_SCALE) + + for (i = 0; i < numcolors; i++) { + icolor = GETJSAMPLE(colorlist[i]); + /* Compute (square of) distance from minc0/c1/c2 to this color */ + inc0 = (minc0 - GETJSAMPLE(cinfo->colormap[0][icolor])) * C0_SCALE; + dist0 = inc0*inc0; + inc1 = (minc1 - GETJSAMPLE(cinfo->colormap[1][icolor])) * C1_SCALE; + dist0 += inc1*inc1; + inc2 = (minc2 - GETJSAMPLE(cinfo->colormap[2][icolor])) * C2_SCALE; + dist0 += inc2*inc2; + /* Form the initial difference increments */ + inc0 = inc0 * (2 * STEP_C0) + STEP_C0 * STEP_C0; + inc1 = inc1 * (2 * STEP_C1) + STEP_C1 * STEP_C1; + inc2 = inc2 * (2 * STEP_C2) + STEP_C2 * STEP_C2; + /* Now loop over all cells in box, updating distance per Thomas method */ + bptr = bestdist; + cptr = bestcolor; + xx0 = inc0; + for (ic0 = BOX_C0_ELEMS-1; ic0 >= 0; ic0--) { + dist1 = dist0; + xx1 = inc1; + for (ic1 = BOX_C1_ELEMS-1; ic1 >= 0; ic1--) { + dist2 = dist1; + xx2 = inc2; + for (ic2 = BOX_C2_ELEMS-1; ic2 >= 0; ic2--) { + if (dist2 < *bptr) { + *bptr = dist2; + *cptr = (JSAMPLE) icolor; + } + dist2 += xx2; + xx2 += 2 * STEP_C2 * STEP_C2; + bptr++; + cptr++; + } + dist1 += xx1; + xx1 += 2 * STEP_C1 * STEP_C1; + } + dist0 += xx0; + xx0 += 2 * STEP_C0 * STEP_C0; + } + } +} + + +LOCAL(void) +fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2) +/* Fill the inverse-colormap entries in the update box that contains */ +/* histogram cell c0/c1/c2. (Only that one cell MUST be filled, but */ +/* we can fill as many others as we wish.) */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + hist3d histogram = cquantize->histogram; + int minc0, minc1, minc2; /* lower left corner of update box */ + int ic0, ic1, ic2; + register JSAMPLE * cptr; /* pointer into bestcolor[] array */ + register histptr cachep; /* pointer into main cache array */ + /* This array lists the candidate colormap indexes. */ + JSAMPLE colorlist[MAXNUMCOLORS]; + int numcolors; /* number of candidate colors */ + /* This array holds the actually closest colormap index for each cell. */ + JSAMPLE bestcolor[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS]; + + /* Convert cell coordinates to update box ID */ + c0 >>= BOX_C0_LOG; + c1 >>= BOX_C1_LOG; + c2 >>= BOX_C2_LOG; + + /* Compute true coordinates of update box's origin corner. + * Actually we compute the coordinates of the center of the corner + * histogram cell, which are the lower bounds of the volume we care about. + */ + minc0 = (c0 << BOX_C0_SHIFT) + ((1 << C0_SHIFT) >> 1); + minc1 = (c1 << BOX_C1_SHIFT) + ((1 << C1_SHIFT) >> 1); + minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1); + + /* Determine which colormap entries are close enough to be candidates + * for the nearest entry to some cell in the update box. + */ + numcolors = find_nearby_colors(cinfo, minc0, minc1, minc2, colorlist); + + /* Determine the actually nearest colors. */ + find_best_colors(cinfo, minc0, minc1, minc2, numcolors, colorlist, + bestcolor); + + /* Save the best color numbers (plus 1) in the main cache array */ + c0 <<= BOX_C0_LOG; /* convert ID back to base cell indexes */ + c1 <<= BOX_C1_LOG; + c2 <<= BOX_C2_LOG; + cptr = bestcolor; + for (ic0 = 0; ic0 < BOX_C0_ELEMS; ic0++) { + for (ic1 = 0; ic1 < BOX_C1_ELEMS; ic1++) { + cachep = & histogram[c0+ic0][c1+ic1][c2]; + for (ic2 = 0; ic2 < BOX_C2_ELEMS; ic2++) { + *cachep++ = (histcell) (GETJSAMPLE(*cptr++) + 1); + } + } + } +} + + +/* + * Map some rows of pixels to the output colormapped representation. + */ + +METHODDEF(void) +pass2_no_dither (j_decompress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows) +/* This version performs no dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + hist3d histogram = cquantize->histogram; + register JSAMPROW inptr, outptr; + register histptr cachep; + register int c0, c1, c2; + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + + for (row = 0; row < num_rows; row++) { + inptr = input_buf[row]; + outptr = output_buf[row]; + for (col = width; col > 0; col--) { + /* get pixel value and index into the cache */ + c0 = GETJSAMPLE(*inptr++) >> C0_SHIFT; + c1 = GETJSAMPLE(*inptr++) >> C1_SHIFT; + c2 = GETJSAMPLE(*inptr++) >> C2_SHIFT; + cachep = & histogram[c0][c1][c2]; + /* If we have not seen this color before, find nearest colormap entry */ + /* and update the cache */ + if (*cachep == 0) + fill_inverse_cmap(cinfo, c0,c1,c2); + /* Now emit the colormap index for this cell */ + *outptr++ = (JSAMPLE) (*cachep - 1); + } + } +} + + +METHODDEF(void) +pass2_fs_dither (j_decompress_ptr cinfo, + JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows) +/* This version performs Floyd-Steinberg dithering */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + hist3d histogram = cquantize->histogram; + register LOCFSERROR cur0, cur1, cur2; /* current error or pixel value */ + LOCFSERROR belowerr0, belowerr1, belowerr2; /* error for pixel below cur */ + LOCFSERROR bpreverr0, bpreverr1, bpreverr2; /* error for below/prev col */ + register FSERRPTR errorptr; /* => fserrors[] at column before current */ + JSAMPROW inptr; /* => current input pixel */ + JSAMPROW outptr; /* => current output pixel */ + histptr cachep; + int dir; /* +1 or -1 depending on direction */ + int dir3; /* 3*dir, for advancing inptr & errorptr */ + int row; + JDIMENSION col; + JDIMENSION width = cinfo->output_width; + JSAMPLE *range_limit = cinfo->sample_range_limit; + int *error_limit = cquantize->error_limiter; + JSAMPROW colormap0 = cinfo->colormap[0]; + JSAMPROW colormap1 = cinfo->colormap[1]; + JSAMPROW colormap2 = cinfo->colormap[2]; + SHIFT_TEMPS + + for (row = 0; row < num_rows; row++) { + inptr = input_buf[row]; + outptr = output_buf[row]; + if (cquantize->on_odd_row) { + /* work right to left in this row */ + inptr += (width-1) * 3; /* so point to rightmost pixel */ + outptr += width-1; + dir = -1; + dir3 = -3; + errorptr = cquantize->fserrors + (width+1)*3; /* => entry after last column */ + cquantize->on_odd_row = FALSE; /* flip for next time */ + } else { + /* work left to right in this row */ + dir = 1; + dir3 = 3; + errorptr = cquantize->fserrors; /* => entry before first real column */ + cquantize->on_odd_row = TRUE; /* flip for next time */ + } + /* Preset error values: no error propagated to first pixel from left */ + cur0 = cur1 = cur2 = 0; + /* and no error propagated to row below yet */ + belowerr0 = belowerr1 = belowerr2 = 0; + bpreverr0 = bpreverr1 = bpreverr2 = 0; + + for (col = width; col > 0; col--) { + /* curN holds the error propagated from the previous pixel on the + * current line. Add the error propagated from the previous line + * to form the complete error correction term for this pixel, and + * round the error term (which is expressed * 16) to an integer. + * RIGHT_SHIFT rounds towards minus infinity, so adding 8 is correct + * for either sign of the error value. + * Note: errorptr points to *previous* column's array entry. + */ + cur0 = RIGHT_SHIFT(cur0 + errorptr[dir3+0] + 8, 4); + cur1 = RIGHT_SHIFT(cur1 + errorptr[dir3+1] + 8, 4); + cur2 = RIGHT_SHIFT(cur2 + errorptr[dir3+2] + 8, 4); + /* Limit the error using transfer function set by init_error_limit. + * See comments with init_error_limit for rationale. + */ + cur0 = error_limit[cur0]; + cur1 = error_limit[cur1]; + cur2 = error_limit[cur2]; + /* Form pixel value + error, and range-limit to 0..MAXJSAMPLE. + * The maximum error is +- MAXJSAMPLE (or less with error limiting); + * this sets the required size of the range_limit array. + */ + cur0 += GETJSAMPLE(inptr[0]); + cur1 += GETJSAMPLE(inptr[1]); + cur2 += GETJSAMPLE(inptr[2]); + cur0 = GETJSAMPLE(range_limit[cur0]); + cur1 = GETJSAMPLE(range_limit[cur1]); + cur2 = GETJSAMPLE(range_limit[cur2]); + /* Index into the cache with adjusted pixel value */ + cachep = & histogram[cur0>>C0_SHIFT][cur1>>C1_SHIFT][cur2>>C2_SHIFT]; + /* If we have not seen this color before, find nearest colormap */ + /* entry and update the cache */ + if (*cachep == 0) + fill_inverse_cmap(cinfo, cur0>>C0_SHIFT,cur1>>C1_SHIFT,cur2>>C2_SHIFT); + /* Now emit the colormap index for this cell */ + { register int pixcode = *cachep - 1; + *outptr = (JSAMPLE) pixcode; + /* Compute representation error for this pixel */ + cur0 -= GETJSAMPLE(colormap0[pixcode]); + cur1 -= GETJSAMPLE(colormap1[pixcode]); + cur2 -= GETJSAMPLE(colormap2[pixcode]); + } + /* Compute error fractions to be propagated to adjacent pixels. + * Add these into the running sums, and simultaneously shift the + * next-line error sums left by 1 column. + */ + { register LOCFSERROR bnexterr, delta; + + bnexterr = cur0; /* Process component 0 */ + delta = cur0 * 2; + cur0 += delta; /* form error * 3 */ + errorptr[0] = (FSERROR) (bpreverr0 + cur0); + cur0 += delta; /* form error * 5 */ + bpreverr0 = belowerr0 + cur0; + belowerr0 = bnexterr; + cur0 += delta; /* form error * 7 */ + bnexterr = cur1; /* Process component 1 */ + delta = cur1 * 2; + cur1 += delta; /* form error * 3 */ + errorptr[1] = (FSERROR) (bpreverr1 + cur1); + cur1 += delta; /* form error * 5 */ + bpreverr1 = belowerr1 + cur1; + belowerr1 = bnexterr; + cur1 += delta; /* form error * 7 */ + bnexterr = cur2; /* Process component 2 */ + delta = cur2 * 2; + cur2 += delta; /* form error * 3 */ + errorptr[2] = (FSERROR) (bpreverr2 + cur2); + cur2 += delta; /* form error * 5 */ + bpreverr2 = belowerr2 + cur2; + belowerr2 = bnexterr; + cur2 += delta; /* form error * 7 */ + } + /* At this point curN contains the 7/16 error value to be propagated + * to the next pixel on the current line, and all the errors for the + * next line have been shifted over. We are therefore ready to move on. + */ + inptr += dir3; /* Advance pixel pointers to next column */ + outptr += dir; + errorptr += dir3; /* advance errorptr to current column */ + } + /* Post-loop cleanup: we must unload the final error values into the + * final fserrors[] entry. Note we need not unload belowerrN because + * it is for the dummy column before or after the actual array. + */ + errorptr[0] = (FSERROR) bpreverr0; /* unload prev errs into array */ + errorptr[1] = (FSERROR) bpreverr1; + errorptr[2] = (FSERROR) bpreverr2; + } +} + + +/* + * Initialize the error-limiting transfer function (lookup table). + * The raw F-S error computation can potentially compute error values of up to + * +- MAXJSAMPLE. But we want the maximum correction applied to a pixel to be + * much less, otherwise obviously wrong pixels will be created. (Typical + * effects include weird fringes at color-area boundaries, isolated bright + * pixels in a dark area, etc.) The standard advice for avoiding this problem + * is to ensure that the "corners" of the color cube are allocated as output + * colors; then repeated errors in the same direction cannot cause cascading + * error buildup. However, that only prevents the error from getting + * completely out of hand; Aaron Giles reports that error limiting improves + * the results even with corner colors allocated. + * A simple clamping of the error values to about +- MAXJSAMPLE/8 works pretty + * well, but the smoother transfer function used below is even better. Thanks + * to Aaron Giles for this idea. + */ + +LOCAL(void) +init_error_limit (j_decompress_ptr cinfo) +/* Allocate and fill in the error_limiter table */ +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + int * table; + int in, out; + + table = (int *) (*cinfo->mem->alloc_small) + ((j_common_ptr) cinfo, JPOOL_IMAGE, (MAXJSAMPLE*2+1) * SIZEOF(int)); + table += MAXJSAMPLE; /* so can index -MAXJSAMPLE .. +MAXJSAMPLE */ + cquantize->error_limiter = table; + +#define STEPSIZE ((MAXJSAMPLE+1)/16) + /* Map errors 1:1 up to +- MAXJSAMPLE/16 */ + out = 0; + for (in = 0; in < STEPSIZE; in++, out++) { + table[in] = out; table[-in] = -out; + } + /* Map errors 1:2 up to +- 3*MAXJSAMPLE/16 */ + for (; in < STEPSIZE*3; in++, out += (in&1) ? 0 : 1) { + table[in] = out; table[-in] = -out; + } + /* Clamp the rest to final out value (which is (MAXJSAMPLE+1)/8) */ + for (; in <= MAXJSAMPLE; in++) { + table[in] = out; table[-in] = -out; + } +#undef STEPSIZE +} + + +/* + * Finish up at the end of each pass. + */ + +METHODDEF(void) +finish_pass1 (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + + /* Select the representative colors and fill in cinfo->colormap */ + cinfo->colormap = cquantize->sv_colormap; + select_colors(cinfo, cquantize->desired); + /* Force next pass to zero the color index table */ + cquantize->needs_zeroed = TRUE; +} + + +METHODDEF(void) +finish_pass2 (j_decompress_ptr cinfo) +{ + (void)cinfo; + /* no work */ +} + + +/* + * Initialize for each processing pass. + */ + +METHODDEF(void) +start_pass_2_quant (j_decompress_ptr cinfo, boolean is_pre_scan) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + hist3d histogram = cquantize->histogram; + int i; + + /* Only F-S dithering or no dithering is supported. */ + /* If user asks for ordered dither, give him F-S. */ + if (cinfo->dither_mode != JDITHER_NONE) + cinfo->dither_mode = JDITHER_FS; + + if (is_pre_scan) { + /* Set up method pointers */ + cquantize->pub.color_quantize = prescan_quantize; + cquantize->pub.finish_pass = finish_pass1; + cquantize->needs_zeroed = TRUE; /* Always zero histogram */ + } else { + /* Set up method pointers */ + if (cinfo->dither_mode == JDITHER_FS) + cquantize->pub.color_quantize = pass2_fs_dither; + else + cquantize->pub.color_quantize = pass2_no_dither; + cquantize->pub.finish_pass = finish_pass2; + + /* Make sure color count is acceptable */ + i = cinfo->actual_number_of_colors; + if (i < 1) + ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 1); + if (i > MAXNUMCOLORS) + ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS); + + if (cinfo->dither_mode == JDITHER_FS) { + size_t arraysize = (size_t) ((cinfo->output_width + 2) * + (3 * SIZEOF(FSERROR))); + /* Allocate Floyd-Steinberg workspace if we didn't already. */ + if (cquantize->fserrors == NULL) + cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large) + ((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize); + /* Initialize the propagated errors to zero. */ + jzero_far((void FAR *) cquantize->fserrors, arraysize); + /* Make the error-limit table if we didn't already. */ + if (cquantize->error_limiter == NULL) + init_error_limit(cinfo); + cquantize->on_odd_row = FALSE; + } + + } + /* Zero the histogram or inverse color map, if necessary */ + if (cquantize->needs_zeroed) { + for (i = 0; i < HIST_C0_ELEMS; i++) { + jzero_far((void FAR *) histogram[i], + HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell)); + } + cquantize->needs_zeroed = FALSE; + } +} + + +/* + * Switch to a new external colormap between output passes. + */ + +METHODDEF(void) +new_color_map_2_quant (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize; + + /* Reset the inverse color map */ + cquantize->needs_zeroed = TRUE; +} + + +/* + * Module initialization routine for 2-pass color quantization. + */ + +GLOBAL(void) +jinit_2pass_quantizer (j_decompress_ptr cinfo) +{ + my_cquantize_ptr cquantize; + int i; + + cquantize = (my_cquantize_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(my_cquantizer)); + cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize; + cquantize->pub.start_pass = start_pass_2_quant; + cquantize->pub.new_color_map = new_color_map_2_quant; + cquantize->fserrors = NULL; /* flag optional arrays not allocated */ + cquantize->error_limiter = NULL; + + /* Make sure jdmaster didn't give me a case I can't handle */ + if (cinfo->out_color_components != 3) + ERREXIT(cinfo, JERR_NOTIMPL); + + /* Allocate the histogram/inverse colormap storage */ + cquantize->histogram = (hist3d) (*cinfo->mem->alloc_small) + ((j_common_ptr) cinfo, JPOOL_IMAGE, HIST_C0_ELEMS * SIZEOF(hist2d)); + for (i = 0; i < HIST_C0_ELEMS; i++) { + cquantize->histogram[i] = (hist2d) (*cinfo->mem->alloc_large) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell)); + } + cquantize->needs_zeroed = TRUE; /* histogram is garbage now */ + + /* Allocate storage for the completed colormap, if required. + * We do this now since it is FAR storage and may affect + * the memory manager's space calculations. + */ + if (cinfo->enable_2pass_quant) { + /* Make sure color count is acceptable */ + int desired = cinfo->desired_number_of_colors; + /* Lower bound on # of colors ... somewhat arbitrary as long as > 0 */ + if (desired < 8) + ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 8); + /* Make sure colormap indexes can be represented by JSAMPLEs */ + if (desired > MAXNUMCOLORS) + ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS); + cquantize->sv_colormap = (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo,JPOOL_IMAGE, (JDIMENSION) desired, (JDIMENSION) 3); + cquantize->desired = desired; + } else + cquantize->sv_colormap = NULL; + + /* Only F-S dithering or no dithering is supported. */ + /* If user asks for ordered dither, give him F-S. */ + if (cinfo->dither_mode != JDITHER_NONE) + cinfo->dither_mode = JDITHER_FS; + + /* Allocate Floyd-Steinberg workspace if necessary. + * This isn't really needed until pass 2, but again it is FAR storage. + * Although we will cope with a later change in dither_mode, + * we do not promise to honor max_memory_to_use if dither_mode changes. + */ + if (cinfo->dither_mode == JDITHER_FS) { + cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (size_t) ((cinfo->output_width + 2) * (3 * SIZEOF(FSERROR)))); + /* Might as well create the error-limiting table too. */ + init_error_limit(cinfo); + } +} + +#endif /* QUANT_2PASS_SUPPORTED */ diff --git a/src/gdcmjpeg/jutils.c b/src/gdcmjpeg/jutils.c new file mode 100644 index 00000000..23abeb88 --- /dev/null +++ b/src/gdcmjpeg/jutils.c @@ -0,0 +1,179 @@ +/* + * jutils.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains tables and miscellaneous utility routines needed + * for both compression and decompression. + * Note we prefix all global names with "j" to minimize conflicts with + * a surrounding application. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* + * jpeg_zigzag_order[i] is the zigzag-order position of the i'th element + * of a DCT block read in natural order (left to right, top to bottom). + */ + +#if 0 /* This table is not actually needed in v6a */ + +const int jpeg_zigzag_order[DCTSIZE2] = { + 0, 1, 5, 6, 14, 15, 27, 28, + 2, 4, 7, 13, 16, 26, 29, 42, + 3, 8, 12, 17, 25, 30, 41, 43, + 9, 11, 18, 24, 31, 40, 44, 53, + 10, 19, 23, 32, 39, 45, 52, 54, + 20, 22, 33, 38, 46, 51, 55, 60, + 21, 34, 37, 47, 50, 56, 59, 61, + 35, 36, 48, 49, 57, 58, 62, 63 +}; + +#endif + +/* + * jpeg_natural_order[i] is the natural-order position of the i'th element + * of zigzag order. + * + * When reading corrupted data, the Huffman decoders could attempt + * to reference an entry beyond the end of this array (if the decoded + * zero run length reaches past the end of the block). To prevent + * wild stores without adding an inner-loop test, we put some extra + * "63"s after the real entries. This will cause the extra coefficient + * to be stored in location 63 of the block, not somewhere random. + * The worst case would be a run-length of 15, which means we need 16 + * fake entries. + */ + +const int jpeg_natural_order[DCTSIZE2+16] = { + 0, 1, 8, 16, 9, 2, 3, 10, + 17, 24, 32, 25, 18, 11, 4, 5, + 12, 19, 26, 33, 40, 48, 41, 34, + 27, 20, 13, 6, 7, 14, 21, 28, + 35, 42, 49, 56, 57, 50, 43, 36, + 29, 22, 15, 23, 30, 37, 44, 51, + 58, 59, 52, 45, 38, 31, 39, 46, + 53, 60, 61, 54, 47, 55, 62, 63, + 63, 63, 63, 63, 63, 63, 63, 63, /* extra entries for safety in decoder */ + 63, 63, 63, 63, 63, 63, 63, 63 +}; + + +/* + * Arithmetic utilities + */ + +GLOBAL(long) +jdiv_round_up (long a, long b) +/* Compute a/b rounded up to next integer, ie, ceil(a/b) */ +/* Assumes a >= 0, b > 0 */ +{ + return (a + b - 1L) / b; +} + + +GLOBAL(long) +jround_up (long a, long b) +/* Compute a rounded up to next multiple of b, ie, ceil(a/b)*b */ +/* Assumes a >= 0, b > 0 */ +{ + a += b - 1L; + return a - (a % b); +} + + +/* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays + * and coefficient-block arrays. This won't work on 80x86 because the arrays + * are FAR and we're assuming a small-pointer memory model. However, some + * DOS compilers provide far-pointer versions of memcpy() and memset() even + * in the small-model libraries. These will be used if USE_FMEM is defined. + * Otherwise, the routines below do it the hard way. (The performance cost + * is not all that great, because these routines aren't very heavily used.) + */ + +#ifndef NEED_FAR_POINTERS /* normal case, same as regular macros */ +#define FMEMCOPY(dest,src,size) MEMCOPY(dest,src,size) +#define FMEMZERO(target,size) MEMZERO(target,size) +#else /* 80x86 case, define if we can */ +#ifdef USE_FMEM +#define FMEMCOPY(dest,src,size) _fmemcpy((void FAR *)(dest), (const void FAR *)(src), (size_t)(size)) +#define FMEMZERO(target,size) _fmemset((void FAR *)(target), 0, (size_t)(size)) +#endif +#endif + + +GLOBAL(void) +jcopy_sample_rows (JSAMPARRAY input_array, int source_row, + JSAMPARRAY output_array, int dest_row, + int num_rows, JDIMENSION num_cols) +/* Copy some rows of samples from one place to another. + * num_rows rows are copied from input_array[source_row++] + * to output_array[dest_row++]; these areas may overlap for duplication. + * The source and destination arrays must be at least as wide as num_cols. + */ +{ + register JSAMPROW inptr, outptr; +#ifdef FMEMCOPY + register size_t count = (size_t) (num_cols * SIZEOF(JSAMPLE)); +#else + register JDIMENSION count; +#endif + register int row; + + input_array += source_row; + output_array += dest_row; + + for (row = num_rows; row > 0; row--) { + inptr = *input_array++; + outptr = *output_array++; +#ifdef FMEMCOPY + FMEMCOPY(outptr, inptr, count); +#else + for (count = num_cols; count > 0; count--) + *outptr++ = *inptr++; /* needn't bother with GETJSAMPLE() here */ +#endif + } +} + + +GLOBAL(void) +jcopy_block_row (JBLOCKROW input_row, JBLOCKROW output_row, + JDIMENSION num_blocks) +/* Copy a row of coefficient blocks from one place to another. */ +{ +#ifdef FMEMCOPY + FMEMCOPY(output_row, input_row, num_blocks * (DCTSIZE2 * SIZEOF(JCOEF))); +#else + register JCOEFPTR inptr, outptr; + register long count; + + inptr = (JCOEFPTR) input_row; + outptr = (JCOEFPTR) output_row; + for (count = (long) num_blocks * DCTSIZE2; count > 0; count--) { + *outptr++ = *inptr++; + } +#endif +} + + +GLOBAL(void) +jzero_far (void FAR * target, size_t bytestozero) +/* Zero out a chunk of FAR memory. */ +/* This might be sample-array data, block-array data, or alloc_large data. */ +{ +#ifdef FMEMZERO + FMEMZERO(target, bytestozero); +#else + register char FAR * ptr = (char FAR *) target; + register size_t count; + + for (count = bytestozero; count > 0; count--) { + *ptr++ = 0; + } +#endif +} diff --git a/src/gdcmjpeg/jversion.h b/src/gdcmjpeg/jversion.h new file mode 100644 index 00000000..95d81303 --- /dev/null +++ b/src/gdcmjpeg/jversion.h @@ -0,0 +1,14 @@ +/* + * jversion.h + * + * Copyright (C) 1991-1998, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains software version identification. + */ + + +#define JVERSION "6b 27-Mar-1998" + +#define JCOPYRIGHT "Copyright (C) 1998, Thomas G. Lane" diff --git a/src/gdcmjpeg/libjpeg.doc b/src/gdcmjpeg/libjpeg.doc new file mode 100644 index 00000000..20ce7b48 --- /dev/null +++ b/src/gdcmjpeg/libjpeg.doc @@ -0,0 +1,3011 @@ +USING THE IJG JPEG LIBRARY + +Copyright (C) 1994-1998, Thomas G. Lane. +This file is part of the Independent JPEG Group's software. +For conditions of distribution and use, see the accompanying README file. + + +This file describes how to use the IJG JPEG library within an application +program. Read it if you want to write a program that uses the library. + +The file example.c provides heavily commented skeleton code for calling the +JPEG library. Also see jpeglib.h (the include file to be used by application +programs) for full details about data structures and function parameter lists. +The library source code, of course, is the ultimate reference. + +Note that there have been *major* changes from the application interface +presented by IJG version 4 and earlier versions. The old design had several +inherent limitations, and it had accumulated a lot of cruft as we added +features while trying to minimize application-interface changes. We have +sacrificed backward compatibility in the version 5 rewrite, but we think the +improvements justify this. + + +TABLE OF CONTENTS +----------------- + +Overview: + Functions provided by the library + Outline of typical usage +Basic library usage: + Data formats + Compression details + Decompression details + Mechanics of usage: include files, linking, etc +Advanced features: + Compression parameter selection + Decompression parameter selection + Special color spaces + Error handling + Compressed data handling (source and destination managers) + I/O suspension + Progressive JPEG support + Buffered-image mode + Abbreviated datastreams and multiple images + Special markers + Raw (downsampled) image data + Really raw data: DCT coefficients + Progress monitoring + Memory management + Memory usage + Library compile-time options + Portability considerations + Notes for MS-DOS implementors + +You should read at least the overview and basic usage sections before trying +to program with the library. The sections on advanced features can be read +if and when you need them. + + +OVERVIEW +======== + +Functions provided by the library +--------------------------------- + +The IJG JPEG library provides C code to read and write JPEG-compressed image +files. The surrounding application program receives or supplies image data a +scanline at a time, using a straightforward uncompressed image format. All +details of color conversion and other preprocessing/postprocessing can be +handled by the library. + +The library includes a substantial amount of code that is not covered by the +JPEG standard but is necessary for typical applications of JPEG. These +functions preprocess the image before JPEG compression or postprocess it after +decompression. They include colorspace conversion, downsampling/upsampling, +and color quantization. The application indirectly selects use of this code +by specifying the format in which it wishes to supply or receive image data. +For example, if colormapped output is requested, then the decompression +library automatically invokes color quantization. + +A wide range of quality vs. speed tradeoffs are possible in JPEG processing, +and even more so in decompression postprocessing. The decompression library +provides multiple implementations that cover most of the useful tradeoffs, +ranging from very-high-quality down to fast-preview operation. On the +compression side we have generally not provided low-quality choices, since +compression is normally less time-critical. It should be understood that the +low-quality modes may not meet the JPEG standard's accuracy requirements; +nonetheless, they are useful for viewers. + +A word about functions *not* provided by the library. We handle a subset of +the ISO JPEG standard; most baseline, extended-sequential, and progressive +JPEG processes are supported. (Our subset includes all features now in common +use.) Unsupported ISO options include: + * Hierarchical storage + * Arithmetic entropy coding (unsupported for legal reasons) + * DNL marker + * Nonintegral subsampling ratios +We support both 8- and 12-bit data precision, but this is a compile-time +choice rather than a run-time choice; hence it is difficult to use both +precisions in a single application. + +By itself, the library handles only interchange JPEG datastreams --- in +particular the widely used JFIF file format. The library can be used by +surrounding code to process interchange or abbreviated JPEG datastreams that +are embedded in more complex file formats. (For example, this library is +used by the free LIBTIFF library to support JPEG compression in TIFF.) + + +Outline of typical usage +------------------------ + +The rough outline of a JPEG compression operation is: + + Allocate and initialize a JPEG compression object + Specify the destination for the compressed data (eg, a file) + Set parameters for compression, including image size & colorspace + jpeg_start_compress(...); + while (scan lines remain to be written) + jpeg_write_scanlines(...); + jpeg_finish_compress(...); + Release the JPEG compression object + +A JPEG compression object holds parameters and working state for the JPEG +library. We make creation/destruction of the object separate from starting +or finishing compression of an image; the same object can be re-used for a +series of image compression operations. This makes it easy to re-use the +same parameter settings for a sequence of images. Re-use of a JPEG object +also has important implications for processing abbreviated JPEG datastreams, +as discussed later. + +The image data to be compressed is supplied to jpeg_write_scanlines() from +in-memory buffers. If the application is doing file-to-file compression, +reading image data from the source file is the application's responsibility. +The library emits compressed data by calling a "data destination manager", +which typically will write the data into a file; but the application can +provide its own destination manager to do something else. + +Similarly, the rough outline of a JPEG decompression operation is: + + Allocate and initialize a JPEG decompression object + Specify the source of the compressed data (eg, a file) + Call jpeg_read_header() to obtain image info + Set parameters for decompression + jpeg_start_decompress(...); + while (scan lines remain to be read) + jpeg_read_scanlines(...); + jpeg_finish_decompress(...); + Release the JPEG decompression object + +This is comparable to the compression outline except that reading the +datastream header is a separate step. This is helpful because information +about the image's size, colorspace, etc is available when the application +selects decompression parameters. For example, the application can choose an +output scaling ratio that will fit the image into the available screen size. + +The decompression library obtains compressed data by calling a data source +manager, which typically will read the data from a file; but other behaviors +can be obtained with a custom source manager. Decompressed data is delivered +into in-memory buffers passed to jpeg_read_scanlines(). + +It is possible to abort an incomplete compression or decompression operation +by calling jpeg_abort(); or, if you do not need to retain the JPEG object, +simply release it by calling jpeg_destroy(). + +JPEG compression and decompression objects are two separate struct types. +However, they share some common fields, and certain routines such as +jpeg_destroy() can work on either type of object. + +The JPEG library has no static variables: all state is in the compression +or decompression object. Therefore it is possible to process multiple +compression and decompression operations concurrently, using multiple JPEG +objects. + +Both compression and decompression can be done in an incremental memory-to- +memory fashion, if suitable source/destination managers are used. See the +section on "I/O suspension" for more details. + + +BASIC LIBRARY USAGE +=================== + +Data formats +------------ + +Before diving into procedural details, it is helpful to understand the +image data format that the JPEG library expects or returns. + +The standard input image format is a rectangular array of pixels, with each +pixel having the same number of "component" or "sample" values (color +channels). You must specify how many components there are and the colorspace +interpretation of the components. Most applications will use RGB data +(three components per pixel) or grayscale data (one component per pixel). +PLEASE NOTE THAT RGB DATA IS THREE SAMPLES PER PIXEL, GRAYSCALE ONLY ONE. +A remarkable number of people manage to miss this, only to find that their +programs don't work with grayscale JPEG files. + +There is no provision for colormapped input. JPEG files are always full-color +or full grayscale (or sometimes another colorspace such as CMYK). You can +feed in a colormapped image by expanding it to full-color format. However +JPEG often doesn't work very well with source data that has been colormapped, +because of dithering noise. This is discussed in more detail in the JPEG FAQ +and the other references mentioned in the README file. + +Pixels are stored by scanlines, with each scanline running from left to +right. The component values for each pixel are adjacent in the row; for +example, R,G,B,R,G,B,R,G,B,... for 24-bit RGB color. Each scanline is an +array of data type JSAMPLE --- which is typically "unsigned char", unless +you've changed jmorecfg.h. (You can also change the RGB pixel layout, say +to B,G,R order, by modifying jmorecfg.h. But see the restrictions listed in +that file before doing so.) + +A 2-D array of pixels is formed by making a list of pointers to the starts of +scanlines; so the scanlines need not be physically adjacent in memory. Even +if you process just one scanline at a time, you must make a one-element +pointer array to conform to this structure. Pointers to JSAMPLE rows are of +type JSAMPROW, and the pointer to the pointer array is of type JSAMPARRAY. + +The library accepts or supplies one or more complete scanlines per call. +It is not possible to process part of a row at a time. Scanlines are always +processed top-to-bottom. You can process an entire image in one call if you +have it all in memory, but usually it's simplest to process one scanline at +a time. + +For best results, source data values should have the precision specified by +BITS_IN_JSAMPLE (normally 8 bits). For instance, if you choose to compress +data that's only 6 bits/channel, you should left-justify each value in a +byte before passing it to the compressor. If you need to compress data +that has more than 8 bits/channel, compile with BITS_IN_JSAMPLE = 12. +(See "Library compile-time options", later.) + + +The data format returned by the decompressor is the same in all details, +except that colormapped output is supported. (Again, a JPEG file is never +colormapped. But you can ask the decompressor to perform on-the-fly color +quantization to deliver colormapped output.) If you request colormapped +output then the returned data array contains a single JSAMPLE per pixel; +its value is an index into a color map. The color map is represented as +a 2-D JSAMPARRAY in which each row holds the values of one color component, +that is, colormap[i][j] is the value of the i'th color component for pixel +value (map index) j. Note that since the colormap indexes are stored in +JSAMPLEs, the maximum number of colors is limited by the size of JSAMPLE +(ie, at most 256 colors for an 8-bit JPEG library). + + +Compression details +------------------- + +Here we revisit the JPEG compression outline given in the overview. + +1. Allocate and initialize a JPEG compression object. + +A JPEG compression object is a "struct jpeg_compress_struct". (It also has +a bunch of subsidiary structures which are allocated via malloc(), but the +application doesn't control those directly.) This struct can be just a local +variable in the calling routine, if a single routine is going to execute the +whole JPEG compression sequence. Otherwise it can be static or allocated +from malloc(). + +You will also need a structure representing a JPEG error handler. The part +of this that the library cares about is a "struct jpeg_error_mgr". If you +are providing your own error handler, you'll typically want to embed the +jpeg_error_mgr struct in a larger structure; this is discussed later under +"Error handling". For now we'll assume you are just using the default error +handler. The default error handler will print JPEG error/warning messages +on stderr, and it will call exit() if a fatal error occurs. + +You must initialize the error handler structure, store a pointer to it into +the JPEG object's "err" field, and then call jpeg_create_compress() to +initialize the rest of the JPEG object. + +Typical code for this step, if you are using the default error handler, is + + struct jpeg_compress_struct cinfo; + struct jpeg_error_mgr jerr; + ... + cinfo.err = jpeg_std_error(&jerr); + jpeg_create_compress(&cinfo); + +jpeg_create_compress allocates a small amount of memory, so it could fail +if you are out of memory. In that case it will exit via the error handler; +that's why the error handler must be initialized first. + + +2. Specify the destination for the compressed data (eg, a file). + +As previously mentioned, the JPEG library delivers compressed data to a +"data destination" module. The library includes one data destination +module which knows how to write to a stdio stream. You can use your own +destination module if you want to do something else, as discussed later. + +If you use the standard destination module, you must open the target stdio +stream beforehand. Typical code for this step looks like: + + FILE * outfile; + ... + if ((outfile = fopen(filename, "wb")) == NULL) { + fprintf(stderr, "can't open %s\n", filename); + exit(1); + } + jpeg_stdio_dest(&cinfo, outfile); + +where the last line invokes the standard destination module. + +WARNING: it is critical that the binary compressed data be delivered to the +output file unchanged. On non-Unix systems the stdio library may perform +newline translation or otherwise corrupt binary data. To suppress this +behavior, you may need to use a "b" option to fopen (as shown above), or use +setmode() or another routine to put the stdio stream in binary mode. See +cjpeg.c and djpeg.c for code that has been found to work on many systems. + +You can select the data destination after setting other parameters (step 3), +if that's more convenient. You may not change the destination between +calling jpeg_start_compress() and jpeg_finish_compress(). + + +3. Set parameters for compression, including image size & colorspace. + +You must supply information about the source image by setting the following +fields in the JPEG object (cinfo structure): + + image_width Width of image, in pixels + image_height Height of image, in pixels + input_components Number of color channels (samples per pixel) + in_color_space Color space of source image + +The image dimensions are, hopefully, obvious. JPEG supports image dimensions +of 1 to 64K pixels in either direction. The input color space is typically +RGB or grayscale, and input_components is 3 or 1 accordingly. (See "Special +color spaces", later, for more info.) The in_color_space field must be +assigned one of the J_COLOR_SPACE enum constants, typically JCS_RGB or +JCS_GRAYSCALE. + +JPEG has a large number of compression parameters that determine how the +image is encoded. Most applications don't need or want to know about all +these parameters. You can set all the parameters to reasonable defaults by +calling jpeg_set_defaults(); then, if there are particular values you want +to change, you can do so after that. The "Compression parameter selection" +section tells about all the parameters. + +You must set in_color_space correctly before calling jpeg_set_defaults(), +because the defaults depend on the source image colorspace. However the +other three source image parameters need not be valid until you call +jpeg_start_compress(). There's no harm in calling jpeg_set_defaults() more +than once, if that happens to be convenient. + +Typical code for a 24-bit RGB source image is + + cinfo.image_width = Width; /* image width and height, in pixels */ + cinfo.image_height = Height; + cinfo.input_components = 3; /* # of color components per pixel */ + cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ + + jpeg_set_defaults(&cinfo); + /* Make optional parameter settings here */ + + +4. jpeg_start_compress(...); + +After you have established the data destination and set all the necessary +source image info and other parameters, call jpeg_start_compress() to begin +a compression cycle. This will initialize internal state, allocate working +storage, and emit the first few bytes of the JPEG datastream header. + +Typical code: + + jpeg_start_compress(&cinfo, TRUE); + +The "TRUE" parameter ensures that a complete JPEG interchange datastream +will be written. This is appropriate in most cases. If you think you might +want to use an abbreviated datastream, read the section on abbreviated +datastreams, below. + +Once you have called jpeg_start_compress(), you may not alter any JPEG +parameters or other fields of the JPEG object until you have completed +the compression cycle. + + +5. while (scan lines remain to be written) + jpeg_write_scanlines(...); + +Now write all the required image data by calling jpeg_write_scanlines() +one or more times. You can pass one or more scanlines in each call, up +to the total image height. In most applications it is convenient to pass +just one or a few scanlines at a time. The expected format for the passed +data is discussed under "Data formats", above. + +Image data should be written in top-to-bottom scanline order. The JPEG spec +contains some weasel wording about how top and bottom are application-defined +terms (a curious interpretation of the English language...) but if you want +your files to be compatible with everyone else's, you WILL use top-to-bottom +order. If the source data must be read in bottom-to-top order, you can use +the JPEG library's virtual array mechanism to invert the data efficiently. +Examples of this can be found in the sample application cjpeg. + +The library maintains a count of the number of scanlines written so far +in the next_scanline field of the JPEG object. Usually you can just use +this variable as the loop counter, so that the loop test looks like +"while (cinfo.next_scanline < cinfo.image_height)". + +Code for this step depends heavily on the way that you store the source data. +example.c shows the following code for the case of a full-size 2-D source +array containing 3-byte RGB pixels: + + JSAMPROW row_pointer[1]; /* pointer to a single row */ + int row_stride; /* physical row width in buffer */ + + row_stride = image_width * 3; /* JSAMPLEs per row in image_buffer */ + + while (cinfo.next_scanline < cinfo.image_height) { + row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride]; + jpeg_write_scanlines(&cinfo, row_pointer, 1); + } + +jpeg_write_scanlines() returns the number of scanlines actually written. +This will normally be equal to the number passed in, so you can usually +ignore the return value. It is different in just two cases: + * If you try to write more scanlines than the declared image height, + the additional scanlines are ignored. + * If you use a suspending data destination manager, output buffer overrun + will cause the compressor to return before accepting all the passed lines. + This feature is discussed under "I/O suspension", below. The normal + stdio destination manager will NOT cause this to happen. +In any case, the return value is the same as the change in the value of +next_scanline. + + +6. jpeg_finish_compress(...); + +After all the image data has been written, call jpeg_finish_compress() to +complete the compression cycle. This step is ESSENTIAL to ensure that the +last bufferload of data is written to the data destination. +jpeg_finish_compress() also releases working memory associated with the JPEG +object. + +Typical code: + + jpeg_finish_compress(&cinfo); + +If using the stdio destination manager, don't forget to close the output +stdio stream (if necessary) afterwards. + +If you have requested a multi-pass operating mode, such as Huffman code +optimization, jpeg_finish_compress() will perform the additional passes using +data buffered by the first pass. In this case jpeg_finish_compress() may take +quite a while to complete. With the default compression parameters, this will +not happen. + +It is an error to call jpeg_finish_compress() before writing the necessary +total number of scanlines. If you wish to abort compression, call +jpeg_abort() as discussed below. + +After completing a compression cycle, you may dispose of the JPEG object +as discussed next, or you may use it to compress another image. In that case +return to step 2, 3, or 4 as appropriate. If you do not change the +destination manager, the new datastream will be written to the same target. +If you do not change any JPEG parameters, the new datastream will be written +with the same parameters as before. Note that you can change the input image +dimensions freely between cycles, but if you change the input colorspace, you +should call jpeg_set_defaults() to adjust for the new colorspace; and then +you'll need to repeat all of step 3. + + +7. Release the JPEG compression object. + +When you are done with a JPEG compression object, destroy it by calling +jpeg_destroy_compress(). This will free all subsidiary memory (regardless of +the previous state of the object). Or you can call jpeg_destroy(), which +works for either compression or decompression objects --- this may be more +convenient if you are sharing code between compression and decompression +cases. (Actually, these routines are equivalent except for the declared type +of the passed pointer. To avoid gripes from ANSI C compilers, jpeg_destroy() +should be passed a j_common_ptr.) + +If you allocated the jpeg_compress_struct structure from malloc(), freeing +it is your responsibility --- jpeg_destroy() won't. Ditto for the error +handler structure. + +Typical code: + + jpeg_destroy_compress(&cinfo); + + +8. Aborting. + +If you decide to abort a compression cycle before finishing, you can clean up +in either of two ways: + +* If you don't need the JPEG object any more, just call + jpeg_destroy_compress() or jpeg_destroy() to release memory. This is + legitimate at any point after calling jpeg_create_compress() --- in fact, + it's safe even if jpeg_create_compress() fails. + +* If you want to re-use the JPEG object, call jpeg_abort_compress(), or call + jpeg_abort() which works on both compression and decompression objects. + This will return the object to an idle state, releasing any working memory. + jpeg_abort() is allowed at any time after successful object creation. + +Note that cleaning up the data destination, if required, is your +responsibility; neither of these routines will call term_destination(). +(See "Compressed data handling", below, for more about that.) + +jpeg_destroy() and jpeg_abort() are the only safe calls to make on a JPEG +object that has reported an error by calling error_exit (see "Error handling" +for more info). The internal state of such an object is likely to be out of +whack. Either of these two routines will return the object to a known state. + + +Decompression details +--------------------- + +Here we revisit the JPEG decompression outline given in the overview. + +1. Allocate and initialize a JPEG decompression object. + +This is just like initialization for compression, as discussed above, +except that the object is a "struct jpeg_decompress_struct" and you +call jpeg_create_decompress(). Error handling is exactly the same. + +Typical code: + + struct jpeg_decompress_struct cinfo; + struct jpeg_error_mgr jerr; + ... + cinfo.err = jpeg_std_error(&jerr); + jpeg_create_decompress(&cinfo); + +(Both here and in the IJG code, we usually use variable name "cinfo" for +both compression and decompression objects.) + + +2. Specify the source of the compressed data (eg, a file). + +As previously mentioned, the JPEG library reads compressed data from a "data +source" module. The library includes one data source module which knows how +to read from a stdio stream. You can use your own source module if you want +to do something else, as discussed later. + +If you use the standard source module, you must open the source stdio stream +beforehand. Typical code for this step looks like: + + FILE * infile; + ... + if ((infile = fopen(filename, "rb")) == NULL) { + fprintf(stderr, "can't open %s\n", filename); + exit(1); + } + jpeg_stdio_src(&cinfo, infile); + +where the last line invokes the standard source module. + +WARNING: it is critical that the binary compressed data be read unchanged. +On non-Unix systems the stdio library may perform newline translation or +otherwise corrupt binary data. To suppress this behavior, you may need to use +a "b" option to fopen (as shown above), or use setmode() or another routine to +put the stdio stream in binary mode. See cjpeg.c and djpeg.c for code that +has been found to work on many systems. + +You may not change the data source between calling jpeg_read_header() and +jpeg_finish_decompress(). If you wish to read a series of JPEG images from +a single source file, you should repeat the jpeg_read_header() to +jpeg_finish_decompress() sequence without reinitializing either the JPEG +object or the data source module; this prevents buffered input data from +being discarded. + + +3. Call jpeg_read_header() to obtain image info. + +Typical code for this step is just + + jpeg_read_header(&cinfo, TRUE); + +This will read the source datastream header markers, up to the beginning +of the compressed data proper. On return, the image dimensions and other +info have been stored in the JPEG object. The application may wish to +consult this information before selecting decompression parameters. + +More complex code is necessary if + * A suspending data source is used --- in that case jpeg_read_header() + may return before it has read all the header data. See "I/O suspension", + below. The normal stdio source manager will NOT cause this to happen. + * Abbreviated JPEG files are to be processed --- see the section on + abbreviated datastreams. Standard applications that deal only in + interchange JPEG files need not be concerned with this case either. + +It is permissible to stop at this point if you just wanted to find out the +image dimensions and other header info for a JPEG file. In that case, +call jpeg_destroy() when you are done with the JPEG object, or call +jpeg_abort() to return it to an idle state before selecting a new data +source and reading another header. + + +4. Set parameters for decompression. + +jpeg_read_header() sets appropriate default decompression parameters based on +the properties of the image (in particular, its colorspace). However, you +may well want to alter these defaults before beginning the decompression. +For example, the default is to produce full color output from a color file. +If you want colormapped output you must ask for it. Other options allow the +returned image to be scaled and allow various speed/quality tradeoffs to be +selected. "Decompression parameter selection", below, gives details. + +If the defaults are appropriate, nothing need be done at this step. + +Note that all default values are set by each call to jpeg_read_header(). +If you reuse a decompression object, you cannot expect your parameter +settings to be preserved across cycles, as you can for compression. +You must set desired parameter values each time. + + +5. jpeg_start_decompress(...); + +Once the parameter values are satisfactory, call jpeg_start_decompress() to +begin decompression. This will initialize internal state, allocate working +memory, and prepare for returning data. + +Typical code is just + + jpeg_start_decompress(&cinfo); + +If you have requested a multi-pass operating mode, such as 2-pass color +quantization, jpeg_start_decompress() will do everything needed before data +output can begin. In this case jpeg_start_decompress() may take quite a while +to complete. With a single-scan (non progressive) JPEG file and default +decompression parameters, this will not happen; jpeg_start_decompress() will +return quickly. + +After this call, the final output image dimensions, including any requested +scaling, are available in the JPEG object; so is the selected colormap, if +colormapped output has been requested. Useful fields include + + output_width image width and height, as scaled + output_height + out_color_components # of color components in out_color_space + output_components # of color components returned per pixel + colormap the selected colormap, if any + actual_number_of_colors number of entries in colormap + +output_components is 1 (a colormap index) when quantizing colors; otherwise it +equals out_color_components. It is the number of JSAMPLE values that will be +emitted per pixel in the output arrays. + +Typically you will need to allocate data buffers to hold the incoming image. +You will need output_width * output_components JSAMPLEs per scanline in your +output buffer, and a total of output_height scanlines will be returned. + +Note: if you are using the JPEG library's internal memory manager to allocate +data buffers (as djpeg does), then the manager's protocol requires that you +request large buffers *before* calling jpeg_start_decompress(). This is a +little tricky since the output_XXX fields are not normally valid then. You +can make them valid by calling jpeg_calc_output_dimensions() after setting the +relevant parameters (scaling, output color space, and quantization flag). + + +6. while (scan lines remain to be read) + jpeg_read_scanlines(...); + +Now you can read the decompressed image data by calling jpeg_read_scanlines() +one or more times. At each call, you pass in the maximum number of scanlines +to be read (ie, the height of your working buffer); jpeg_read_scanlines() +will return up to that many lines. The return value is the number of lines +actually read. The format of the returned data is discussed under "Data +formats", above. Don't forget that grayscale and color JPEGs will return +different data formats! + +Image data is returned in top-to-bottom scanline order. If you must write +out the image in bottom-to-top order, you can use the JPEG library's virtual +array mechanism to invert the data efficiently. Examples of this can be +found in the sample application djpeg. + +The library maintains a count of the number of scanlines returned so far +in the output_scanline field of the JPEG object. Usually you can just use +this variable as the loop counter, so that the loop test looks like +"while (cinfo.output_scanline < cinfo.output_height)". (Note that the test +should NOT be against image_height, unless you never use scaling. The +image_height field is the height of the original unscaled image.) +The return value always equals the change in the value of output_scanline. + +If you don't use a suspending data source, it is safe to assume that +jpeg_read_scanlines() reads at least one scanline per call, until the +bottom of the image has been reached. + +If you use a buffer larger than one scanline, it is NOT safe to assume that +jpeg_read_scanlines() fills it. (The current implementation returns only a +few scanlines per call, no matter how large a buffer you pass.) So you must +always provide a loop that calls jpeg_read_scanlines() repeatedly until the +whole image has been read. + + +7. jpeg_finish_decompress(...); + +After all the image data has been read, call jpeg_finish_decompress() to +complete the decompression cycle. This causes working memory associated +with the JPEG object to be released. + +Typical code: + + jpeg_finish_decompress(&cinfo); + +If using the stdio source manager, don't forget to close the source stdio +stream if necessary. + +It is an error to call jpeg_finish_decompress() before reading the correct +total number of scanlines. If you wish to abort decompression, call +jpeg_abort() as discussed below. + +After completing a decompression cycle, you may dispose of the JPEG object as +discussed next, or you may use it to decompress another image. In that case +return to step 2 or 3 as appropriate. If you do not change the source +manager, the next image will be read from the same source. + + +8. Release the JPEG decompression object. + +When you are done with a JPEG decompression object, destroy it by calling +jpeg_destroy_decompress() or jpeg_destroy(). The previous discussion of +destroying compression objects applies here too. + +Typical code: + + jpeg_destroy_decompress(&cinfo); + + +9. Aborting. + +You can abort a decompression cycle by calling jpeg_destroy_decompress() or +jpeg_destroy() if you don't need the JPEG object any more, or +jpeg_abort_decompress() or jpeg_abort() if you want to reuse the object. +The previous discussion of aborting compression cycles applies here too. + + +Mechanics of usage: include files, linking, etc +----------------------------------------------- + +Applications using the JPEG library should include the header file jpeglib.h +to obtain declarations of data types and routines. Before including +jpeglib.h, include system headers that define at least the typedefs FILE and +size_t. On ANSI-conforming systems, including is sufficient; on +older Unix systems, you may need to define size_t. + +If the application needs to refer to individual JPEG library error codes, also +include jerror.h to define those symbols. + +jpeglib.h indirectly includes the files jconfig.h and jmorecfg.h. If you are +installing the JPEG header files in a system directory, you will want to +install all four files: jpeglib.h, jerror.h, jconfig.h, jmorecfg.h. + +The most convenient way to include the JPEG code into your executable program +is to prepare a library file ("libjpeg.a", or a corresponding name on non-Unix +machines) and reference it at your link step. If you use only half of the +library (only compression or only decompression), only that much code will be +included from the library, unless your linker is hopelessly brain-damaged. +The supplied makefiles build libjpeg.a automatically (see install.doc). + +While you can build the JPEG library as a shared library if the whim strikes +you, we don't really recommend it. The trouble with shared libraries is that +at some point you'll probably try to substitute a new version of the library +without recompiling the calling applications. That generally doesn't work +because the parameter struct declarations usually change with each new +version. In other words, the library's API is *not* guaranteed binary +compatible across versions; we only try to ensure source-code compatibility. +(In hindsight, it might have been smarter to hide the parameter structs from +applications and introduce a ton of access functions instead. Too late now, +however.) + +On some systems your application may need to set up a signal handler to ensure +that temporary files are deleted if the program is interrupted. This is most +critical if you are on MS-DOS and use the jmemdos.c memory manager back end; +it will try to grab extended memory for temp files, and that space will NOT be +freed automatically. See cjpeg.c or djpeg.c for an example signal handler. + +It may be worth pointing out that the core JPEG library does not actually +require the stdio library: only the default source/destination managers and +error handler need it. You can use the library in a stdio-less environment +if you replace those modules and use jmemnobs.c (or another memory manager of +your own devising). More info about the minimum system library requirements +may be found in jinclude.h. + + +ADVANCED FEATURES +================= + +Compression parameter selection +------------------------------- + +This section describes all the optional parameters you can set for JPEG +compression, as well as the "helper" routines provided to assist in this +task. Proper setting of some parameters requires detailed understanding +of the JPEG standard; if you don't know what a parameter is for, it's best +not to mess with it! See REFERENCES in the README file for pointers to +more info about JPEG. + +It's a good idea to call jpeg_set_defaults() first, even if you plan to set +all the parameters; that way your code is more likely to work with future JPEG +libraries that have additional parameters. For the same reason, we recommend +you use a helper routine where one is provided, in preference to twiddling +cinfo fields directly. + +The helper routines are: + +jpeg_set_defaults (j_compress_ptr cinfo) + This routine sets all JPEG parameters to reasonable defaults, using + only the input image's color space (field in_color_space, which must + already be set in cinfo). Many applications will only need to use + this routine and perhaps jpeg_set_quality(). + +jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace) + Sets the JPEG file's colorspace (field jpeg_color_space) as specified, + and sets other color-space-dependent parameters appropriately. See + "Special color spaces", below, before using this. A large number of + parameters, including all per-component parameters, are set by this + routine; if you want to twiddle individual parameters you should call + jpeg_set_colorspace() before rather than after. + +jpeg_default_colorspace (j_compress_ptr cinfo) + Selects an appropriate JPEG colorspace based on cinfo->in_color_space, + and calls jpeg_set_colorspace(). This is actually a subroutine of + jpeg_set_defaults(). It's broken out in case you want to change + just the colorspace-dependent JPEG parameters. + +jpeg_set_quality (j_compress_ptr cinfo, int quality, boolean force_baseline) + Constructs JPEG quantization tables appropriate for the indicated + quality setting. The quality value is expressed on the 0..100 scale + recommended by IJG (cjpeg's "-quality" switch uses this routine). + Note that the exact mapping from quality values to tables may change + in future IJG releases as more is learned about DCT quantization. + If the force_baseline parameter is TRUE, then the quantization table + entries are constrained to the range 1..255 for full JPEG baseline + compatibility. In the current implementation, this only makes a + difference for quality settings below 25, and it effectively prevents + very small/low quality files from being generated. The IJG decoder + is capable of reading the non-baseline files generated at low quality + settings when force_baseline is FALSE, but other decoders may not be. + +jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor, + boolean force_baseline) + Same as jpeg_set_quality() except that the generated tables are the + sample tables given in the JPEC spec section K.1, multiplied by the + specified scale factor (which is expressed as a percentage; thus + scale_factor = 100 reproduces the spec's tables). Note that larger + scale factors give lower quality. This entry point is useful for + conforming to the Adobe PostScript DCT conventions, but we do not + recommend linear scaling as a user-visible quality scale otherwise. + force_baseline again constrains the computed table entries to 1..255. + +int jpeg_quality_scaling (int quality) + Converts a value on the IJG-recommended quality scale to a linear + scaling percentage. Note that this routine may change or go away + in future releases --- IJG may choose to adopt a scaling method that + can't be expressed as a simple scalar multiplier, in which case the + premise of this routine collapses. Caveat user. + +jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl, + const unsigned int *basic_table, + int scale_factor, boolean force_baseline) + Allows an arbitrary quantization table to be created. which_tbl + indicates which table slot to fill. basic_table points to an array + of 64 unsigned ints given in normal array order. These values are + multiplied by scale_factor/100 and then clamped to the range 1..65535 + (or to 1..255 if force_baseline is TRUE). + CAUTION: prior to library version 6a, jpeg_add_quant_table expected + the basic table to be given in JPEG zigzag order. If you need to + write code that works with either older or newer versions of this + routine, you must check the library version number. Something like + "#if JPEG_LIB_VERSION >= 61" is the right test. + +jpeg_simple_progression (j_compress_ptr cinfo) + Generates a default scan script for writing a progressive-JPEG file. + This is the recommended method of creating a progressive file, + unless you want to make a custom scan sequence. You must ensure that + the JPEG color space is set correctly before calling this routine. + +jpeg_simple_lossless (j_compress_ptr cinfo, int predictor, int point_transform) + Generates a default scan script for writing a lossless-JPEG file. + This is the recommended method of creating a lossless file, + unless you want to make a custom scan sequence. You must ensure that + the JPEG color space is set correctly before calling this routine. + + +Compression parameters (cinfo fields) include: + +J_DCT_METHOD dct_method + Selects the algorithm used for the DCT step. Choices are: + JDCT_ISLOW: slow but accurate integer algorithm + JDCT_IFAST: faster, less accurate integer method + JDCT_FLOAT: floating-point method + JDCT_DEFAULT: default method (normally JDCT_ISLOW) + JDCT_FASTEST: fastest method (normally JDCT_IFAST) + The FLOAT method is very slightly more accurate than the ISLOW method, + but may give different results on different machines due to varying + roundoff behavior. The integer methods should give the same results + on all machines. On machines with sufficiently fast FP hardware, the + floating-point method may also be the fastest. The IFAST method is + considerably less accurate than the other two; its use is not + recommended if high quality is a concern. JDCT_DEFAULT and + JDCT_FASTEST are macros configurable by each installation. + +J_COLOR_SPACE jpeg_color_space +int num_components + The JPEG color space and corresponding number of components; see + "Special color spaces", below, for more info. We recommend using + jpeg_set_color_space() if you want to change these. + +boolean optimize_coding + TRUE causes the compressor to compute optimal Huffman coding tables + for the image. This requires an extra pass over the data and + therefore costs a good deal of space and time. The default is + FALSE, which tells the compressor to use the supplied or default + Huffman tables. In most cases optimal tables save only a few percent + of file size compared to the default tables. Note that when this is + TRUE, you need not supply Huffman tables at all, and any you do + supply will be overwritten. + +unsigned int restart_interval +int restart_in_rows + To emit restart markers in the JPEG file, set one of these nonzero. + Set restart_interval to specify the exact interval in MCU blocks. + Set restart_in_rows to specify the interval in MCU rows. (If + restart_in_rows is not 0, then restart_interval is set after the + image width in MCUs is computed.) Defaults are zero (no restarts). + One restart marker per MCU row is often a good choice. + NOTE: the overhead of restart markers is higher in grayscale JPEG + files than in color files, and MUCH higher in progressive JPEGs. + If you use restarts, you may want to use larger intervals in those + cases. + +const jpeg_scan_info * scan_info +int num_scans + By default, scan_info is NULL; this causes the compressor to write a + single-scan sequential JPEG file. If not NULL, scan_info points to + an array of scan definition records of length num_scans. The + compressor will then write a JPEG file having one scan for each scan + definition record. This is used to generate noninterleaved or + progressive JPEG files. The library checks that the scan array + defines a valid JPEG scan sequence. (jpeg_simple_progression creates + a suitable scan definition array for progressive JPEG.) This is + discussed further under "Progressive JPEG support". + +int smoothing_factor + If non-zero, the input image is smoothed; the value should be 1 for + minimal smoothing to 100 for maximum smoothing. Consult jcsample.c + for details of the smoothing algorithm. The default is zero. + +boolean write_JFIF_header + If TRUE, a JFIF APP0 marker is emitted. jpeg_set_defaults() and + jpeg_set_colorspace() set this TRUE if a JFIF-legal JPEG color space + (ie, YCbCr or grayscale) is selected, otherwise FALSE. + +UINT8 JFIF_major_version +UINT8 JFIF_minor_version + The version number to be written into the JFIF marker. + jpeg_set_defaults() initializes the version to 1.01 (major=minor=1). + You should set it to 1.02 (major=1, minor=2) if you plan to write + any JFIF 1.02 extension markers. + +UINT8 density_unit +UINT16 X_density +UINT16 Y_density + The resolution information to be written into the JFIF marker; + not used otherwise. density_unit may be 0 for unknown, + 1 for dots/inch, or 2 for dots/cm. The default values are 0,1,1 + indicating square pixels of unknown size. + +boolean write_Adobe_marker + If TRUE, an Adobe APP14 marker is emitted. jpeg_set_defaults() and + jpeg_set_colorspace() set this TRUE if JPEG color space RGB, CMYK, + or YCCK is selected, otherwise FALSE. It is generally a bad idea + to set both write_JFIF_header and write_Adobe_marker. In fact, + you probably shouldn't change the default settings at all --- the + default behavior ensures that the JPEG file's color space can be + recognized by the decoder. + +JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS] + Pointers to coefficient quantization tables, one per table slot, + or NULL if no table is defined for a slot. Usually these should + be set via one of the above helper routines; jpeg_add_quant_table() + is general enough to define any quantization table. The other + routines will set up table slot 0 for luminance quality and table + slot 1 for chrominance. + +JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS] +JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS] + Pointers to Huffman coding tables, one per table slot, or NULL if + no table is defined for a slot. Slots 0 and 1 are filled with the + JPEG sample tables by jpeg_set_defaults(). If you need to allocate + more table structures, jpeg_alloc_huff_table() may be used. + Note that optimal Huffman tables can be computed for an image + by setting optimize_coding, as discussed above; there's seldom + any need to mess with providing your own Huffman tables. + +There are some additional cinfo fields which are not documented here +because you currently can't change them; for example, you can't set +arith_code TRUE because arithmetic coding is unsupported. + + +Per-component parameters are stored in the struct cinfo.comp_info[i] for +component number i. Note that components here refer to components of the +JPEG color space, *not* the source image color space. A suitably large +comp_info[] array is allocated by jpeg_set_defaults(); if you choose not +to use that routine, it's up to you to allocate the array. + +int component_id + The one-byte identifier code to be recorded in the JPEG file for + this component. For the standard color spaces, we recommend you + leave the default values alone. + +int h_samp_factor +int v_samp_factor + Horizontal and vertical sampling factors for the component; must + be 1..4 according to the JPEG standard. Note that larger sampling + factors indicate a higher-resolution component; many people find + this behavior quite unintuitive. The default values are 2,2 for + luminance components and 1,1 for chrominance components, except + for grayscale where 1,1 is used. + +int quant_tbl_no + Quantization table number for component. The default value is + 0 for luminance components and 1 for chrominance components. + +int dc_tbl_no +int ac_tbl_no + DC and AC entropy coding table numbers. The default values are + 0 for luminance components and 1 for chrominance components. + +int component_index + Must equal the component's index in comp_info[]. (Beginning in + release v6, the compressor library will fill this in automatically; + you don't have to.) + + +Decompression parameter selection +--------------------------------- + +Decompression parameter selection is somewhat simpler than compression +parameter selection, since all of the JPEG internal parameters are +recorded in the source file and need not be supplied by the application. +(Unless you are working with abbreviated files, in which case see +"Abbreviated datastreams", below.) Decompression parameters control +the postprocessing done on the image to deliver it in a format suitable +for the application's use. Many of the parameters control speed/quality +tradeoffs, in which faster decompression may be obtained at the price of +a poorer-quality image. The defaults select the highest quality (slowest) +processing. + +The following fields in the JPEG object are set by jpeg_read_header() and +may be useful to the application in choosing decompression parameters: + +JDIMENSION image_width Width and height of image +JDIMENSION image_height +int num_components Number of color components +J_COLOR_SPACE jpeg_color_space Colorspace of image +boolean saw_JFIF_marker TRUE if a JFIF APP0 marker was seen + UINT8 JFIF_major_version Version information from JFIF marker + UINT8 JFIF_minor_version + UINT8 density_unit Resolution data from JFIF marker + UINT16 X_density + UINT16 Y_density +boolean saw_Adobe_marker TRUE if an Adobe APP14 marker was seen + UINT8 Adobe_transform Color transform code from Adobe marker + +The JPEG color space, unfortunately, is something of a guess since the JPEG +standard proper does not provide a way to record it. In practice most files +adhere to the JFIF or Adobe conventions, and the decoder will recognize these +correctly. See "Special color spaces", below, for more info. + + +The decompression parameters that determine the basic properties of the +returned image are: + +J_COLOR_SPACE out_color_space + Output color space. jpeg_read_header() sets an appropriate default + based on jpeg_color_space; typically it will be RGB or grayscale. + The application can change this field to request output in a different + colorspace. For example, set it to JCS_GRAYSCALE to get grayscale + output from a color file. (This is useful for previewing: grayscale + output is faster than full color since the color components need not + be processed.) Note that not all possible color space transforms are + currently implemented; you may need to extend jdcolor.c if you want an + unusual conversion. + +unsigned int scale_num, scale_denom + Scale the image by the fraction scale_num/scale_denom. Default is + 1/1, or no scaling. Currently, the only supported scaling ratios + are 1/1, 1/2, 1/4, and 1/8. (The library design allows for arbitrary + scaling ratios but this is not likely to be implemented any time soon.) + Smaller scaling ratios permit significantly faster decoding since + fewer pixels need be processed and a simpler IDCT method can be used. + +boolean quantize_colors + If set TRUE, colormapped output will be delivered. Default is FALSE, + meaning that full-color output will be delivered. + +The next three parameters are relevant only if quantize_colors is TRUE. + +int desired_number_of_colors + Maximum number of colors to use in generating a library-supplied color + map (the actual number of colors is returned in a different field). + Default 256. Ignored when the application supplies its own color map. + +boolean two_pass_quantize + If TRUE, an extra pass over the image is made to select a custom color + map for the image. This usually looks a lot better than the one-size- + fits-all colormap that is used otherwise. Default is TRUE. Ignored + when the application supplies its own color map. + +J_DITHER_MODE dither_mode + Selects color dithering method. Supported values are: + JDITHER_NONE no dithering: fast, very low quality + JDITHER_ORDERED ordered dither: moderate speed and quality + JDITHER_FS Floyd-Steinberg dither: slow, high quality + Default is JDITHER_FS. (At present, ordered dither is implemented + only in the single-pass, standard-colormap case. If you ask for + ordered dither when two_pass_quantize is TRUE or when you supply + an external color map, you'll get F-S dithering.) + +When quantize_colors is TRUE, the target color map is described by the next +two fields. colormap is set to NULL by jpeg_read_header(). The application +can supply a color map by setting colormap non-NULL and setting +actual_number_of_colors to the map size. Otherwise, jpeg_start_decompress() +selects a suitable color map and sets these two fields itself. +[Implementation restriction: at present, an externally supplied colormap is +only accepted for 3-component output color spaces.] + +JSAMPARRAY colormap + The color map, represented as a 2-D pixel array of out_color_components + rows and actual_number_of_colors columns. Ignored if not quantizing. + CAUTION: if the JPEG library creates its own colormap, the storage + pointed to by this field is released by jpeg_finish_decompress(). + Copy the colormap somewhere else first, if you want to save it. + +int actual_number_of_colors + The number of colors in the color map. + +Additional decompression parameters that the application may set include: + +J_DCT_METHOD dct_method + Selects the algorithm used for the DCT step. Choices are the same + as described above for compression. + +boolean do_fancy_upsampling + If TRUE, do careful upsampling of chroma components. If FALSE, + a faster but sloppier method is used. Default is TRUE. The visual + impact of the sloppier method is often very small. + +boolean do_block_smoothing + If TRUE, interblock smoothing is applied in early stages of decoding + progressive JPEG files; if FALSE, not. Default is TRUE. Early + progression stages look "fuzzy" with smoothing, "blocky" without. + In any case, block smoothing ceases to be applied after the first few + AC coefficients are known to full accuracy, so it is relevant only + when using buffered-image mode for progressive images. + +boolean enable_1pass_quant +boolean enable_external_quant +boolean enable_2pass_quant + These are significant only in buffered-image mode, which is + described in its own section below. + + +The output image dimensions are given by the following fields. These are +computed from the source image dimensions and the decompression parameters +by jpeg_start_decompress(). You can also call jpeg_calc_output_dimensions() +to obtain the values that will result from the current parameter settings. +This can be useful if you are trying to pick a scaling ratio that will get +close to a desired target size. It's also important if you are using the +JPEG library's memory manager to allocate output buffer space, because you +are supposed to request such buffers *before* jpeg_start_decompress(). + +JDIMENSION output_width Actual dimensions of output image. +JDIMENSION output_height +int out_color_components Number of color components in out_color_space. +int output_components Number of color components returned. +int rec_outbuf_height Recommended height of scanline buffer. + +When quantizing colors, output_components is 1, indicating a single color map +index per pixel. Otherwise it equals out_color_components. The output arrays +are required to be output_width * output_components JSAMPLEs wide. + +rec_outbuf_height is the recommended minimum height (in scanlines) of the +buffer passed to jpeg_read_scanlines(). If the buffer is smaller, the +library will still work, but time will be wasted due to unnecessary data +copying. In high-quality modes, rec_outbuf_height is always 1, but some +faster, lower-quality modes set it to larger values (typically 2 to 4). +If you are going to ask for a high-speed processing mode, you may as well +go to the trouble of honoring rec_outbuf_height so as to avoid data copying. +(An output buffer larger than rec_outbuf_height lines is OK, but won't +provide any material speed improvement over that height.) + + +Special color spaces +-------------------- + +The JPEG standard itself is "color blind" and doesn't specify any particular +color space. It is customary to convert color data to a luminance/chrominance +color space before compressing, since this permits greater compression. The +existing de-facto JPEG file format standards specify YCbCr or grayscale data +(JFIF), or grayscale, RGB, YCbCr, CMYK, or YCCK (Adobe). For special +applications such as multispectral images, other color spaces can be used, +but it must be understood that such files will be unportable. + +The JPEG library can handle the most common colorspace conversions (namely +RGB <=> YCbCr and CMYK <=> YCCK). It can also deal with data of an unknown +color space, passing it through without conversion. If you deal extensively +with an unusual color space, you can easily extend the library to understand +additional color spaces and perform appropriate conversions. + +For compression, the source data's color space is specified by field +in_color_space. This is transformed to the JPEG file's color space given +by jpeg_color_space. jpeg_set_defaults() chooses a reasonable JPEG color +space depending on in_color_space, but you can override this by calling +jpeg_set_colorspace(). Of course you must select a supported transformation. +jccolor.c currently supports the following transformations: + RGB => YCbCr + RGB => GRAYSCALE + YCbCr => GRAYSCALE + CMYK => YCCK +plus the null transforms: GRAYSCALE => GRAYSCALE, RGB => RGB, +YCbCr => YCbCr, CMYK => CMYK, YCCK => YCCK, and UNKNOWN => UNKNOWN. + +The de-facto file format standards (JFIF and Adobe) specify APPn markers that +indicate the color space of the JPEG file. It is important to ensure that +these are written correctly, or omitted if the JPEG file's color space is not +one of the ones supported by the de-facto standards. jpeg_set_colorspace() +will set the compression parameters to include or omit the APPn markers +properly, so long as it is told the truth about the JPEG color space. +For example, if you are writing some random 3-component color space without +conversion, don't try to fake out the library by setting in_color_space and +jpeg_color_space to JCS_YCbCr; use JCS_UNKNOWN. You may want to write an +APPn marker of your own devising to identify the colorspace --- see "Special +markers", below. + +When told that the color space is UNKNOWN, the library will default to using +luminance-quality compression parameters for all color components. You may +well want to change these parameters. See the source code for +jpeg_set_colorspace(), in jcparam.c, for details. + +For decompression, the JPEG file's color space is given in jpeg_color_space, +and this is transformed to the output color space out_color_space. +jpeg_read_header's setting of jpeg_color_space can be relied on if the file +conforms to JFIF or Adobe conventions, but otherwise it is no better than a +guess. If you know the JPEG file's color space for certain, you can override +jpeg_read_header's guess by setting jpeg_color_space. jpeg_read_header also +selects a default output color space based on (its guess of) jpeg_color_space; +set out_color_space to override this. Again, you must select a supported +transformation. jdcolor.c currently supports + YCbCr => GRAYSCALE + YCbCr => RGB + GRAYSCALE => RGB + YCCK => CMYK +as well as the null transforms. (Since GRAYSCALE=>RGB is provided, an +application can force grayscale JPEGs to look like color JPEGs if it only +wants to handle one case.) + +The two-pass color quantizer, jquant2.c, is specialized to handle RGB data +(it weights distances appropriately for RGB colors). You'll need to modify +the code if you want to use it for non-RGB output color spaces. Note that +jquant2.c is used to map to an application-supplied colormap as well as for +the normal two-pass colormap selection process. + +CAUTION: it appears that Adobe Photoshop writes inverted data in CMYK JPEG +files: 0 represents 100% ink coverage, rather than 0% ink as you'd expect. +This is arguably a bug in Photoshop, but if you need to work with Photoshop +CMYK files, you will have to deal with it in your application. We cannot +"fix" this in the library by inverting the data during the CMYK<=>YCCK +transform, because that would break other applications, notably Ghostscript. +Photoshop versions prior to 3.0 write EPS files containing JPEG-encoded CMYK +data in the same inverted-YCCK representation used in bare JPEG files, but +the surrounding PostScript code performs an inversion using the PS image +operator. I am told that Photoshop 3.0 will write uninverted YCCK in +EPS/JPEG files, and will omit the PS-level inversion. (But the data +polarity used in bare JPEG files will not change in 3.0.) In either case, +the JPEG library must not invert the data itself, or else Ghostscript would +read these EPS files incorrectly. + + +Error handling +-------------- + +When the default error handler is used, any error detected inside the JPEG +routines will cause a message to be printed on stderr, followed by exit(). +You can supply your own error handling routines to override this behavior +and to control the treatment of nonfatal warnings and trace/debug messages. +The file example.c illustrates the most common case, which is to have the +application regain control after an error rather than exiting. + +The JPEG library never writes any message directly; it always goes through +the error handling routines. Three classes of messages are recognized: + * Fatal errors: the library cannot continue. + * Warnings: the library can continue, but the data is corrupt, and a + damaged output image is likely to result. + * Trace/informational messages. These come with a trace level indicating + the importance of the message; you can control the verbosity of the + program by adjusting the maximum trace level that will be displayed. + +You may, if you wish, simply replace the entire JPEG error handling module +(jerror.c) with your own code. However, you can avoid code duplication by +only replacing some of the routines depending on the behavior you need. +This is accomplished by calling jpeg_std_error() as usual, but then overriding +some of the method pointers in the jpeg_error_mgr struct, as illustrated by +example.c. + +All of the error handling routines will receive a pointer to the JPEG object +(a j_common_ptr which points to either a jpeg_compress_struct or a +jpeg_decompress_struct; if you need to tell which, test the is_decompressor +field). This struct includes a pointer to the error manager struct in its +"err" field. Frequently, custom error handler routines will need to access +additional data which is not known to the JPEG library or the standard error +handler. The most convenient way to do this is to embed either the JPEG +object or the jpeg_error_mgr struct in a larger structure that contains +additional fields; then casting the passed pointer provides access to the +additional fields. Again, see example.c for one way to do it. (Beginning +with IJG version 6b, there is also a void pointer "client_data" in each +JPEG object, which the application can also use to find related data. +The library does not touch client_data at all.) + +The individual methods that you might wish to override are: + +error_exit (j_common_ptr cinfo) + Receives control for a fatal error. Information sufficient to + generate the error message has been stored in cinfo->err; call + output_message to display it. Control must NOT return to the caller; + generally this routine will exit() or longjmp() somewhere. + Typically you would override this routine to get rid of the exit() + default behavior. Note that if you continue processing, you should + clean up the JPEG object with jpeg_abort() or jpeg_destroy(). + +output_message (j_common_ptr cinfo) + Actual output of any JPEG message. Override this to send messages + somewhere other than stderr. Note that this method does not know + how to generate a message, only where to send it. + +format_message (j_common_ptr cinfo, char * buffer) + Constructs a readable error message string based on the error info + stored in cinfo->err. This method is called by output_message. Few + applications should need to override this method. One possible + reason for doing so is to implement dynamic switching of error message + language. + +emit_message (j_common_ptr cinfo, int msg_level) + Decide whether or not to emit a warning or trace message; if so, + calls output_message. The main reason for overriding this method + would be to abort on warnings. msg_level is -1 for warnings, + 0 and up for trace messages. + +Only error_exit() and emit_message() are called from the rest of the JPEG +library; the other two are internal to the error handler. + +The actual message texts are stored in an array of strings which is pointed to +by the field err->jpeg_message_table. The messages are numbered from 0 to +err->last_jpeg_message, and it is these code numbers that are used in the +JPEG library code. You could replace the message texts (for instance, with +messages in French or German) by changing the message table pointer. See +jerror.h for the default texts. CAUTION: this table will almost certainly +change or grow from one library version to the next. + +It may be useful for an application to add its own message texts that are +handled by the same mechanism. The error handler supports a second "add-on" +message table for this purpose. To define an addon table, set the pointer +err->addon_message_table and the message numbers err->first_addon_message and +err->last_addon_message. If you number the addon messages beginning at 1000 +or so, you won't have to worry about conflicts with the library's built-in +messages. See the sample applications cjpeg/djpeg for an example of using +addon messages (the addon messages are defined in cderror.h). + +Actual invocation of the error handler is done via macros defined in jerror.h: + ERREXITn(...) for fatal errors + WARNMSn(...) for corrupt-data warnings + TRACEMSn(...) for trace and informational messages. +These macros store the message code and any additional parameters into the +error handler struct, then invoke the error_exit() or emit_message() method. +The variants of each macro are for varying numbers of additional parameters. +The additional parameters are inserted into the generated message using +standard printf() format codes. + +See jerror.h and jerror.c for further details. + + +Compressed data handling (source and destination managers) +---------------------------------------------------------- + +The JPEG compression library sends its compressed data to a "destination +manager" module. The default destination manager just writes the data to a +stdio stream, but you can provide your own manager to do something else. +Similarly, the decompression library calls a "source manager" to obtain the +compressed data; you can provide your own source manager if you want the data +to come from somewhere other than a stdio stream. + +In both cases, compressed data is processed a bufferload at a time: the +destination or source manager provides a work buffer, and the library invokes +the manager only when the buffer is filled or emptied. (You could define a +one-character buffer to force the manager to be invoked for each byte, but +that would be rather inefficient.) The buffer's size and location are +controlled by the manager, not by the library. For example, if you desired to +decompress a JPEG datastream that was all in memory, you could just make the +buffer pointer and length point to the original data in memory. Then the +buffer-reload procedure would be invoked only if the decompressor ran off the +end of the datastream, which would indicate an erroneous datastream. + +The work buffer is defined as an array of datatype JOCTET, which is generally +"char" or "unsigned char". On a machine where char is not exactly 8 bits +wide, you must define JOCTET as a wider data type and then modify the data +source and destination modules to transcribe the work arrays into 8-bit units +on external storage. + +A data destination manager struct contains a pointer and count defining the +next byte to write in the work buffer and the remaining free space: + + JOCTET * next_output_byte; /* => next byte to write in buffer */ + size_t free_in_buffer; /* # of byte spaces remaining in buffer */ + +The library increments the pointer and decrements the count until the buffer +is filled. The manager's empty_output_buffer method must reset the pointer +and count. The manager is expected to remember the buffer's starting address +and total size in private fields not visible to the library. + +A data destination manager provides three methods: + +init_destination (j_compress_ptr cinfo) + Initialize destination. This is called by jpeg_start_compress() + before any data is actually written. It must initialize + next_output_byte and free_in_buffer. free_in_buffer must be + initialized to a positive value. + +empty_output_buffer (j_compress_ptr cinfo) + This is called whenever the buffer has filled (free_in_buffer + reaches zero). In typical applications, it should write out the + *entire* buffer (use the saved start address and buffer length; + ignore the current state of next_output_byte and free_in_buffer). + Then reset the pointer & count to the start of the buffer, and + return TRUE indicating that the buffer has been dumped. + free_in_buffer must be set to a positive value when TRUE is + returned. A FALSE return should only be used when I/O suspension is + desired (this operating mode is discussed in the next section). + +term_destination (j_compress_ptr cinfo) + Terminate destination --- called by jpeg_finish_compress() after all + data has been written. In most applications, this must flush any + data remaining in the buffer. Use either next_output_byte or + free_in_buffer to determine how much data is in the buffer. + +term_destination() is NOT called by jpeg_abort() or jpeg_destroy(). If you +want the destination manager to be cleaned up during an abort, you must do it +yourself. + +You will also need code to create a jpeg_destination_mgr struct, fill in its +method pointers, and insert a pointer to the struct into the "dest" field of +the JPEG compression object. This can be done in-line in your setup code if +you like, but it's probably cleaner to provide a separate routine similar to +the jpeg_stdio_dest() routine of the supplied destination manager. + +Decompression source managers follow a parallel design, but with some +additional frammishes. The source manager struct contains a pointer and count +defining the next byte to read from the work buffer and the number of bytes +remaining: + + const JOCTET * next_input_byte; /* => next byte to read from buffer */ + size_t bytes_in_buffer; /* # of bytes remaining in buffer */ + +The library increments the pointer and decrements the count until the buffer +is emptied. The manager's fill_input_buffer method must reset the pointer and +count. In most applications, the manager must remember the buffer's starting +address and total size in private fields not visible to the library. + +A data source manager provides five methods: + +init_source (j_decompress_ptr cinfo) + Initialize source. This is called by jpeg_read_header() before any + data is actually read. Unlike init_destination(), it may leave + bytes_in_buffer set to 0 (in which case a fill_input_buffer() call + will occur immediately). + +fill_input_buffer (j_decompress_ptr cinfo) + This is called whenever bytes_in_buffer has reached zero and more + data is wanted. In typical applications, it should read fresh data + into the buffer (ignoring the current state of next_input_byte and + bytes_in_buffer), reset the pointer & count to the start of the + buffer, and return TRUE indicating that the buffer has been reloaded. + It is not necessary to fill the buffer entirely, only to obtain at + least one more byte. bytes_in_buffer MUST be set to a positive value + if TRUE is returned. A FALSE return should only be used when I/O + suspension is desired (this mode is discussed in the next section). + +skip_input_data (j_decompress_ptr cinfo, long num_bytes) + Skip num_bytes worth of data. The buffer pointer and count should + be advanced over num_bytes input bytes, refilling the buffer as + needed. This is used to skip over a potentially large amount of + uninteresting data (such as an APPn marker). In some applications + it may be possible to optimize away the reading of the skipped data, + but it's not clear that being smart is worth much trouble; large + skips are uncommon. bytes_in_buffer may be zero on return. + A zero or negative skip count should be treated as a no-op. + +resync_to_restart (j_decompress_ptr cinfo, int desired) + This routine is called only when the decompressor has failed to find + a restart (RSTn) marker where one is expected. Its mission is to + find a suitable point for resuming decompression. For most + applications, we recommend that you just use the default resync + procedure, jpeg_resync_to_restart(). However, if you are able to back + up in the input data stream, or if you have a-priori knowledge about + the likely location of restart markers, you may be able to do better. + Read the read_restart_marker() and jpeg_resync_to_restart() routines + in jdmarker.c if you think you'd like to implement your own resync + procedure. + +term_source (j_decompress_ptr cinfo) + Terminate source --- called by jpeg_finish_decompress() after all + data has been read. Often a no-op. + +For both fill_input_buffer() and skip_input_data(), there is no such thing +as an EOF return. If the end of the file has been reached, the routine has +a choice of exiting via ERREXIT() or inserting fake data into the buffer. +In most cases, generating a warning message and inserting a fake EOI marker +is the best course of action --- this will allow the decompressor to output +however much of the image is there. In pathological cases, the decompressor +may swallow the EOI and again demand data ... just keep feeding it fake EOIs. +jdatasrc.c illustrates the recommended error recovery behavior. + +term_source() is NOT called by jpeg_abort() or jpeg_destroy(). If you want +the source manager to be cleaned up during an abort, you must do it yourself. + +You will also need code to create a jpeg_source_mgr struct, fill in its method +pointers, and insert a pointer to the struct into the "src" field of the JPEG +decompression object. This can be done in-line in your setup code if you +like, but it's probably cleaner to provide a separate routine similar to the +jpeg_stdio_src() routine of the supplied source manager. + +For more information, consult the stdio source and destination managers +in jdatasrc.c and jdatadst.c. + + +I/O suspension +-------------- + +Some applications need to use the JPEG library as an incremental memory-to- +memory filter: when the compressed data buffer is filled or emptied, they want +control to return to the outer loop, rather than expecting that the buffer can +be emptied or reloaded within the data source/destination manager subroutine. +The library supports this need by providing an "I/O suspension" mode, which we +describe in this section. + +The I/O suspension mode is not a panacea: nothing is guaranteed about the +maximum amount of time spent in any one call to the library, so it will not +eliminate response-time problems in single-threaded applications. If you +need guaranteed response time, we suggest you "bite the bullet" and implement +a real multi-tasking capability. + +To use I/O suspension, cooperation is needed between the calling application +and the data source or destination manager; you will always need a custom +source/destination manager. (Please read the previous section if you haven't +already.) The basic idea is that the empty_output_buffer() or +fill_input_buffer() routine is a no-op, merely returning FALSE to indicate +that it has done nothing. Upon seeing this, the JPEG library suspends +operation and returns to its caller. The surrounding application is +responsible for emptying or refilling the work buffer before calling the +JPEG library again. + +Compression suspension: + +For compression suspension, use an empty_output_buffer() routine that returns +FALSE; typically it will not do anything else. This will cause the +compressor to return to the caller of jpeg_write_scanlines(), with the return +value indicating that not all the supplied scanlines have been accepted. +The application must make more room in the output buffer, adjust the output +buffer pointer/count appropriately, and then call jpeg_write_scanlines() +again, pointing to the first unconsumed scanline. + +When forced to suspend, the compressor will backtrack to a convenient stopping +point (usually the start of the current MCU); it will regenerate some output +data when restarted. Therefore, although empty_output_buffer() is only +called when the buffer is filled, you should NOT write out the entire buffer +after a suspension. Write only the data up to the current position of +next_output_byte/free_in_buffer. The data beyond that point will be +regenerated after resumption. + +Because of the backtracking behavior, a good-size output buffer is essential +for efficiency; you don't want the compressor to suspend often. (In fact, an +overly small buffer could lead to infinite looping, if a single MCU required +more data than would fit in the buffer.) We recommend a buffer of at least +several Kbytes. You may want to insert explicit code to ensure that you don't +call jpeg_write_scanlines() unless there is a reasonable amount of space in +the output buffer; in other words, flush the buffer before trying to compress +more data. + +The compressor does not allow suspension while it is trying to write JPEG +markers at the beginning and end of the file. This means that: + * At the beginning of a compression operation, there must be enough free + space in the output buffer to hold the header markers (typically 600 or + so bytes). The recommended buffer size is bigger than this anyway, so + this is not a problem as long as you start with an empty buffer. However, + this restriction might catch you if you insert large special markers, such + as a JFIF thumbnail image, without flushing the buffer afterwards. + * When you call jpeg_finish_compress(), there must be enough space in the + output buffer to emit any buffered data and the final EOI marker. In the + current implementation, half a dozen bytes should suffice for this, but + for safety's sake we recommend ensuring that at least 100 bytes are free + before calling jpeg_finish_compress(). + +A more significant restriction is that jpeg_finish_compress() cannot suspend. +This means you cannot use suspension with multi-pass operating modes, namely +Huffman code optimization and multiple-scan output. Those modes write the +whole file during jpeg_finish_compress(), which will certainly result in +buffer overrun. (Note that this restriction applies only to compression, +not decompression. The decompressor supports input suspension in all of its +operating modes.) + +Decompression suspension: + +For decompression suspension, use a fill_input_buffer() routine that simply +returns FALSE (except perhaps during error recovery, as discussed below). +This will cause the decompressor to return to its caller with an indication +that suspension has occurred. This can happen at four places: + * jpeg_read_header(): will return JPEG_SUSPENDED. + * jpeg_start_decompress(): will return FALSE, rather than its usual TRUE. + * jpeg_read_scanlines(): will return the number of scanlines already + completed (possibly 0). + * jpeg_finish_decompress(): will return FALSE, rather than its usual TRUE. +The surrounding application must recognize these cases, load more data into +the input buffer, and repeat the call. In the case of jpeg_read_scanlines(), +increment the passed pointers past any scanlines successfully read. + +Just as with compression, the decompressor will typically backtrack to a +convenient restart point before suspending. When fill_input_buffer() is +called, next_input_byte/bytes_in_buffer point to the current restart point, +which is where the decompressor will backtrack to if FALSE is returned. +The data beyond that position must NOT be discarded if you suspend; it needs +to be re-read upon resumption. In most implementations, you'll need to shift +this data down to the start of your work buffer and then load more data after +it. Again, this behavior means that a several-Kbyte work buffer is essential +for decent performance; furthermore, you should load a reasonable amount of +new data before resuming decompression. (If you loaded, say, only one new +byte each time around, you could waste a LOT of cycles.) + +The skip_input_data() source manager routine requires special care in a +suspension scenario. This routine is NOT granted the ability to suspend the +decompressor; it can decrement bytes_in_buffer to zero, but no more. If the +requested skip distance exceeds the amount of data currently in the input +buffer, then skip_input_data() must set bytes_in_buffer to zero and record the +additional skip distance somewhere else. The decompressor will immediately +call fill_input_buffer(), which should return FALSE, which will cause a +suspension return. The surrounding application must then arrange to discard +the recorded number of bytes before it resumes loading the input buffer. +(Yes, this design is rather baroque, but it avoids complexity in the far more +common case where a non-suspending source manager is used.) + +If the input data has been exhausted, we recommend that you emit a warning +and insert dummy EOI markers just as a non-suspending data source manager +would do. This can be handled either in the surrounding application logic or +within fill_input_buffer(); the latter is probably more efficient. If +fill_input_buffer() knows that no more data is available, it can set the +pointer/count to point to a dummy EOI marker and then return TRUE just as +though it had read more data in a non-suspending situation. + +The decompressor does not attempt to suspend within standard JPEG markers; +instead it will backtrack to the start of the marker and reprocess the whole +marker next time. Hence the input buffer must be large enough to hold the +longest standard marker in the file. Standard JPEG markers should normally +not exceed a few hundred bytes each (DHT tables are typically the longest). +We recommend at least a 2K buffer for performance reasons, which is much +larger than any correct marker is likely to be. For robustness against +damaged marker length counts, you may wish to insert a test in your +application for the case that the input buffer is completely full and yet +the decoder has suspended without consuming any data --- otherwise, if this +situation did occur, it would lead to an endless loop. (The library can't +provide this test since it has no idea whether "the buffer is full", or +even whether there is a fixed-size input buffer.) + +The input buffer would need to be 64K to allow for arbitrary COM or APPn +markers, but these are handled specially: they are either saved into allocated +memory, or skipped over by calling skip_input_data(). In the former case, +suspension is handled correctly, and in the latter case, the problem of +buffer overrun is placed on skip_input_data's shoulders, as explained above. +Note that if you provide your own marker handling routine for large markers, +you should consider how to deal with buffer overflow. + +Multiple-buffer management: + +In some applications it is desirable to store the compressed data in a linked +list of buffer areas, so as to avoid data copying. This can be handled by +having empty_output_buffer() or fill_input_buffer() set the pointer and count +to reference the next available buffer; FALSE is returned only if no more +buffers are available. Although seemingly straightforward, there is a +pitfall in this approach: the backtrack that occurs when FALSE is returned +could back up into an earlier buffer. For example, when fill_input_buffer() +is called, the current pointer & count indicate the backtrack restart point. +Since fill_input_buffer() will set the pointer and count to refer to a new +buffer, the restart position must be saved somewhere else. Suppose a second +call to fill_input_buffer() occurs in the same library call, and no +additional input data is available, so fill_input_buffer must return FALSE. +If the JPEG library has not moved the pointer/count forward in the current +buffer, then *the correct restart point is the saved position in the prior +buffer*. Prior buffers may be discarded only after the library establishes +a restart point within a later buffer. Similar remarks apply for output into +a chain of buffers. + +The library will never attempt to backtrack over a skip_input_data() call, +so any skipped data can be permanently discarded. You still have to deal +with the case of skipping not-yet-received data, however. + +It's much simpler to use only a single buffer; when fill_input_buffer() is +called, move any unconsumed data (beyond the current pointer/count) down to +the beginning of this buffer and then load new data into the remaining buffer +space. This approach requires a little more data copying but is far easier +to get right. + + +Progressive JPEG support +------------------------ + +Progressive JPEG rearranges the stored data into a series of scans of +increasing quality. In situations where a JPEG file is transmitted across a +slow communications link, a decoder can generate a low-quality image very +quickly from the first scan, then gradually improve the displayed quality as +more scans are received. The final image after all scans are complete is +identical to that of a regular (sequential) JPEG file of the same quality +setting. Progressive JPEG files are often slightly smaller than equivalent +sequential JPEG files, but the possibility of incremental display is the main +reason for using progressive JPEG. + +The IJG encoder library generates progressive JPEG files when given a +suitable "scan script" defining how to divide the data into scans. +Creation of progressive JPEG files is otherwise transparent to the encoder. +Progressive JPEG files can also be read transparently by the decoder library. +If the decoding application simply uses the library as defined above, it +will receive a final decoded image without any indication that the file was +progressive. Of course, this approach does not allow incremental display. +To perform incremental display, an application needs to use the decoder +library's "buffered-image" mode, in which it receives a decoded image +multiple times. + +Each displayed scan requires about as much work to decode as a full JPEG +image of the same size, so the decoder must be fairly fast in relation to the +data transmission rate in order to make incremental display useful. However, +it is possible to skip displaying the image and simply add the incoming bits +to the decoder's coefficient buffer. This is fast because only Huffman +decoding need be done, not IDCT, upsampling, colorspace conversion, etc. +The IJG decoder library allows the application to switch dynamically between +displaying the image and simply absorbing the incoming bits. A properly +coded application can automatically adapt the number of display passes to +suit the time available as the image is received. Also, a final +higher-quality display cycle can be performed from the buffered data after +the end of the file is reached. + +Progressive compression: + +To create a progressive JPEG file (or a multiple-scan sequential JPEG file), +set the scan_info cinfo field to point to an array of scan descriptors, and +perform compression as usual. Instead of constructing your own scan list, +you can call the jpeg_simple_progression() helper routine to create a +recommended progression sequence; this method should be used by all +applications that don't want to get involved in the nitty-gritty of +progressive scan sequence design. (If you want to provide user control of +scan sequences, you may wish to borrow the scan script reading code found +in rdswitch.c, so that you can read scan script files just like cjpeg's.) +When scan_info is not NULL, the compression library will store DCT'd data +into a buffer array as jpeg_write_scanlines() is called, and will emit all +the requested scans during jpeg_finish_compress(). This implies that +multiple-scan output cannot be created with a suspending data destination +manager, since jpeg_finish_compress() does not support suspension. We +should also note that the compressor currently forces Huffman optimization +mode when creating a progressive JPEG file, because the default Huffman +tables are unsuitable for progressive files. + +Progressive decompression: + +When buffered-image mode is not used, the decoder library will read all of +a multi-scan file during jpeg_start_decompress(), so that it can provide a +final decoded image. (Here "multi-scan" means either progressive or +multi-scan sequential.) This makes multi-scan files transparent to the +decoding application. However, existing applications that used suspending +input with version 5 of the IJG library will need to be modified to check +for a suspension return from jpeg_start_decompress(). + +To perform incremental display, an application must use the library's +buffered-image mode. This is described in the next section. + + +Buffered-image mode +------------------- + +In buffered-image mode, the library stores the partially decoded image in a +coefficient buffer, from which it can be read out as many times as desired. +This mode is typically used for incremental display of progressive JPEG files, +but it can be used with any JPEG file. Each scan of a progressive JPEG file +adds more data (more detail) to the buffered image. The application can +display in lockstep with the source file (one display pass per input scan), +or it can allow input processing to outrun display processing. By making +input and display processing run independently, it is possible for the +application to adapt progressive display to a wide range of data transmission +rates. + +The basic control flow for buffered-image decoding is + + jpeg_create_decompress() + set data source + jpeg_read_header() + set overall decompression parameters + cinfo.buffered_image = TRUE; /* select buffered-image mode */ + jpeg_start_decompress() + for (each output pass) { + adjust output decompression parameters if required + jpeg_start_output() /* start a new output pass */ + for (all scanlines in image) { + jpeg_read_scanlines() + display scanlines + } + jpeg_finish_output() /* terminate output pass */ + } + jpeg_finish_decompress() + jpeg_destroy_decompress() + +This differs from ordinary unbuffered decoding in that there is an additional +level of looping. The application can choose how many output passes to make +and how to display each pass. + +The simplest approach to displaying progressive images is to do one display +pass for each scan appearing in the input file. In this case the outer loop +condition is typically + while (! jpeg_input_complete(&cinfo)) +and the start-output call should read + jpeg_start_output(&cinfo, cinfo.input_scan_number); +The second parameter to jpeg_start_output() indicates which scan of the input +file is to be displayed; the scans are numbered starting at 1 for this +purpose. (You can use a loop counter starting at 1 if you like, but using +the library's input scan counter is easier.) The library automatically reads +data as necessary to complete each requested scan, and jpeg_finish_output() +advances to the next scan or end-of-image marker (hence input_scan_number +will be incremented by the time control arrives back at jpeg_start_output()). +With this technique, data is read from the input file only as needed, and +input and output processing run in lockstep. + +After reading the final scan and reaching the end of the input file, the +buffered image remains available; it can be read additional times by +repeating the jpeg_start_output()/jpeg_read_scanlines()/jpeg_finish_output() +sequence. For example, a useful technique is to use fast one-pass color +quantization for display passes made while the image is arriving, followed by +a final display pass using two-pass quantization for highest quality. This +is done by changing the library parameters before the final output pass. +Changing parameters between passes is discussed in detail below. + +In general the last scan of a progressive file cannot be recognized as such +until after it is read, so a post-input display pass is the best approach if +you want special processing in the final pass. + +When done with the image, be sure to call jpeg_finish_decompress() to release +the buffered image (or just use jpeg_destroy_decompress()). + +If input data arrives faster than it can be displayed, the application can +cause the library to decode input data in advance of what's needed to produce +output. This is done by calling the routine jpeg_consume_input(). +The return value is one of the following: + JPEG_REACHED_SOS: reached an SOS marker (the start of a new scan) + JPEG_REACHED_EOI: reached the EOI marker (end of image) + JPEG_ROW_COMPLETED: completed reading one MCU row of compressed data + JPEG_SCAN_COMPLETED: completed reading last MCU row of current scan + JPEG_SUSPENDED: suspended before completing any of the above +(JPEG_SUSPENDED can occur only if a suspending data source is used.) This +routine can be called at any time after initializing the JPEG object. It +reads some additional data and returns when one of the indicated significant +events occurs. (If called after the EOI marker is reached, it will +immediately return JPEG_REACHED_EOI without attempting to read more data.) + +The library's output processing will automatically call jpeg_consume_input() +whenever the output processing overtakes the input; thus, simple lockstep +display requires no direct calls to jpeg_consume_input(). But by adding +calls to jpeg_consume_input(), you can absorb data in advance of what is +being displayed. This has two benefits: + * You can limit buildup of unprocessed data in your input buffer. + * You can eliminate extra display passes by paying attention to the + state of the library's input processing. + +The first of these benefits only requires interspersing calls to +jpeg_consume_input() with your display operations and any other processing +you may be doing. To avoid wasting cycles due to backtracking, it's best to +call jpeg_consume_input() only after a hundred or so new bytes have arrived. +This is discussed further under "I/O suspension", above. (Note: the JPEG +library currently is not thread-safe. You must not call jpeg_consume_input() +from one thread of control if a different library routine is working on the +same JPEG object in another thread.) + +When input arrives fast enough that more than one new scan is available +before you start a new output pass, you may as well skip the output pass +corresponding to the completed scan. This occurs for free if you pass +cinfo.input_scan_number as the target scan number to jpeg_start_output(). +The input_scan_number field is simply the index of the scan currently being +consumed by the input processor. You can ensure that this is up-to-date by +emptying the input buffer just before calling jpeg_start_output(): call +jpeg_consume_input() repeatedly until it returns JPEG_SUSPENDED or +JPEG_REACHED_EOI. + +The target scan number passed to jpeg_start_output() is saved in the +cinfo.output_scan_number field. The library's output processing calls +jpeg_consume_input() whenever the current input scan number and row within +that scan is less than or equal to the current output scan number and row. +Thus, input processing can "get ahead" of the output processing but is not +allowed to "fall behind". You can achieve several different effects by +manipulating this interlock rule. For example, if you pass a target scan +number greater than the current input scan number, the output processor will +wait until that scan starts to arrive before producing any output. (To avoid +an infinite loop, the target scan number is automatically reset to the last +scan number when the end of image is reached. Thus, if you specify a large +target scan number, the library will just absorb the entire input file and +then perform an output pass. This is effectively the same as what +jpeg_start_decompress() does when you don't select buffered-image mode.) +When you pass a target scan number equal to the current input scan number, +the image is displayed no faster than the current input scan arrives. The +final possibility is to pass a target scan number less than the current input +scan number; this disables the input/output interlock and causes the output +processor to simply display whatever it finds in the image buffer, without +waiting for input. (However, the library will not accept a target scan +number less than one, so you can't avoid waiting for the first scan.) + +When data is arriving faster than the output display processing can advance +through the image, jpeg_consume_input() will store data into the buffered +image beyond the point at which the output processing is reading data out +again. If the input arrives fast enough, it may "wrap around" the buffer to +the point where the input is more than one whole scan ahead of the output. +If the output processing simply proceeds through its display pass without +paying attention to the input, the effect seen on-screen is that the lower +part of the image is one or more scans better in quality than the upper part. +Then, when the next output scan is started, you have a choice of what target +scan number to use. The recommended choice is to use the current input scan +number at that time, which implies that you've skipped the output scans +corresponding to the input scans that were completed while you processed the +previous output scan. In this way, the decoder automatically adapts its +speed to the arriving data, by skipping output scans as necessary to keep up +with the arriving data. + +When using this strategy, you'll want to be sure that you perform a final +output pass after receiving all the data; otherwise your last display may not +be full quality across the whole screen. So the right outer loop logic is +something like this: + do { + absorb any waiting input by calling jpeg_consume_input() + final_pass = jpeg_input_complete(&cinfo); + adjust output decompression parameters if required + jpeg_start_output(&cinfo, cinfo.input_scan_number); + ... + jpeg_finish_output() + } while (! final_pass); +rather than quitting as soon as jpeg_input_complete() returns TRUE. This +arrangement makes it simple to use higher-quality decoding parameters +for the final pass. But if you don't want to use special parameters for +the final pass, the right loop logic is like this: + for (;;) { + absorb any waiting input by calling jpeg_consume_input() + jpeg_start_output(&cinfo, cinfo.input_scan_number); + ... + jpeg_finish_output() + if (jpeg_input_complete(&cinfo) && + cinfo.input_scan_number == cinfo.output_scan_number) + break; + } +In this case you don't need to know in advance whether an output pass is to +be the last one, so it's not necessary to have reached EOF before starting +the final output pass; rather, what you want to test is whether the output +pass was performed in sync with the final input scan. This form of the loop +will avoid an extra output pass whenever the decoder is able (or nearly able) +to keep up with the incoming data. + +When the data transmission speed is high, you might begin a display pass, +then find that much or all of the file has arrived before you can complete +the pass. (You can detect this by noting the JPEG_REACHED_EOI return code +from jpeg_consume_input(), or equivalently by testing jpeg_input_complete().) +In this situation you may wish to abort the current display pass and start a +new one using the newly arrived information. To do so, just call +jpeg_finish_output() and then start a new pass with jpeg_start_output(). + +A variant strategy is to abort and restart display if more than one complete +scan arrives during an output pass; this can be detected by noting +JPEG_REACHED_SOS returns and/or examining cinfo.input_scan_number. This +idea should be employed with caution, however, since the display process +might never get to the bottom of the image before being aborted, resulting +in the lower part of the screen being several passes worse than the upper. +In most cases it's probably best to abort an output pass only if the whole +file has arrived and you want to begin the final output pass immediately. + +When receiving data across a communication link, we recommend always using +the current input scan number for the output target scan number; if a +higher-quality final pass is to be done, it should be started (aborting any +incomplete output pass) as soon as the end of file is received. However, +many other strategies are possible. For example, the application can examine +the parameters of the current input scan and decide whether to display it or +not. If the scan contains only chroma data, one might choose not to use it +as the target scan, expecting that the scan will be small and will arrive +quickly. To skip to the next scan, call jpeg_consume_input() until it +returns JPEG_REACHED_SOS or JPEG_REACHED_EOI. Or just use the next higher +number as the target scan for jpeg_start_output(); but that method doesn't +let you inspect the next scan's parameters before deciding to display it. + + +In buffered-image mode, jpeg_start_decompress() never performs input and +thus never suspends. An application that uses input suspension with +buffered-image mode must be prepared for suspension returns from these +routines: +* jpeg_start_output() performs input only if you request 2-pass quantization + and the target scan isn't fully read yet. (This is discussed below.) +* jpeg_read_scanlines(), as always, returns the number of scanlines that it + was able to produce before suspending. +* jpeg_finish_output() will read any markers following the target scan, + up to the end of the file or the SOS marker that begins another scan. + (But it reads no input if jpeg_consume_input() has already reached the + end of the file or a SOS marker beyond the target output scan.) +* jpeg_finish_decompress() will read until the end of file, and thus can + suspend if the end hasn't already been reached (as can be tested by + calling jpeg_input_complete()). +jpeg_start_output(), jpeg_finish_output(), and jpeg_finish_decompress() +all return TRUE if they completed their tasks, FALSE if they had to suspend. +In the event of a FALSE return, the application must load more input data +and repeat the call. Applications that use non-suspending data sources need +not check the return values of these three routines. + + +It is possible to change decoding parameters between output passes in the +buffered-image mode. The decoder library currently supports only very +limited changes of parameters. ONLY THE FOLLOWING parameter changes are +allowed after jpeg_start_decompress() is called: +* dct_method can be changed before each call to jpeg_start_output(). + For example, one could use a fast DCT method for early scans, changing + to a higher quality method for the final scan. +* dither_mode can be changed before each call to jpeg_start_output(); + of course this has no impact if not using color quantization. Typically + one would use ordered dither for initial passes, then switch to + Floyd-Steinberg dither for the final pass. Caution: changing dither mode + can cause more memory to be allocated by the library. Although the amount + of memory involved is not large (a scanline or so), it may cause the + initial max_memory_to_use specification to be exceeded, which in the worst + case would result in an out-of-memory failure. +* do_block_smoothing can be changed before each call to jpeg_start_output(). + This setting is relevant only when decoding a progressive JPEG image. + During the first DC-only scan, block smoothing provides a very "fuzzy" look + instead of the very "blocky" look seen without it; which is better seems a + matter of personal taste. But block smoothing is nearly always a win + during later stages, especially when decoding a successive-approximation + image: smoothing helps to hide the slight blockiness that otherwise shows + up on smooth gradients until the lowest coefficient bits are sent. +* Color quantization mode can be changed under the rules described below. + You *cannot* change between full-color and quantized output (because that + would alter the required I/O buffer sizes), but you can change which + quantization method is used. + +When generating color-quantized output, changing quantization method is a +very useful way of switching between high-speed and high-quality display. +The library allows you to change among its three quantization methods: +1. Single-pass quantization to a fixed color cube. + Selected by cinfo.two_pass_quantize = FALSE and cinfo.colormap = NULL. +2. Single-pass quantization to an application-supplied colormap. + Selected by setting cinfo.colormap to point to the colormap (the value of + two_pass_quantize is ignored); also set cinfo.actual_number_of_colors. +3. Two-pass quantization to a colormap chosen specifically for the image. + Selected by cinfo.two_pass_quantize = TRUE and cinfo.colormap = NULL. + (This is the default setting selected by jpeg_read_header, but it is + probably NOT what you want for the first pass of progressive display!) +These methods offer successively better quality and lesser speed. However, +only the first method is available for quantizing in non-RGB color spaces. + +IMPORTANT: because the different quantizer methods have very different +working-storage requirements, the library requires you to indicate which +one(s) you intend to use before you call jpeg_start_decompress(). (If we did +not require this, the max_memory_to_use setting would be a complete fiction.) +You do this by setting one or more of these three cinfo fields to TRUE: + enable_1pass_quant Fixed color cube colormap + enable_external_quant Externally-supplied colormap + enable_2pass_quant Two-pass custom colormap +All three are initialized FALSE by jpeg_read_header(). But +jpeg_start_decompress() automatically sets TRUE the one selected by the +current two_pass_quantize and colormap settings, so you only need to set the +enable flags for any other quantization methods you plan to change to later. + +After setting the enable flags correctly at jpeg_start_decompress() time, you +can change to any enabled quantization method by setting two_pass_quantize +and colormap properly just before calling jpeg_start_output(). The following +special rules apply: +1. You must explicitly set cinfo.colormap to NULL when switching to 1-pass + or 2-pass mode from a different mode, or when you want the 2-pass + quantizer to be re-run to generate a new colormap. +2. To switch to an external colormap, or to change to a different external + colormap than was used on the prior pass, you must call + jpeg_new_colormap() after setting cinfo.colormap. +NOTE: if you want to use the same colormap as was used in the prior pass, +you should not do either of these things. This will save some nontrivial +switchover costs. +(These requirements exist because cinfo.colormap will always be non-NULL +after completing a prior output pass, since both the 1-pass and 2-pass +quantizers set it to point to their output colormaps. Thus you have to +do one of these two things to notify the library that something has changed. +Yup, it's a bit klugy, but it's necessary to do it this way for backwards +compatibility.) + +Note that in buffered-image mode, the library generates any requested colormap +during jpeg_start_output(), not during jpeg_start_decompress(). + +When using two-pass quantization, jpeg_start_output() makes a pass over the +buffered image to determine the optimum color map; it therefore may take a +significant amount of time, whereas ordinarily it does little work. The +progress monitor hook is called during this pass, if defined. It is also +important to realize that if the specified target scan number is greater than +or equal to the current input scan number, jpeg_start_output() will attempt +to consume input as it makes this pass. If you use a suspending data source, +you need to check for a FALSE return from jpeg_start_output() under these +conditions. The combination of 2-pass quantization and a not-yet-fully-read +target scan is the only case in which jpeg_start_output() will consume input. + + +Application authors who support buffered-image mode may be tempted to use it +for all JPEG images, even single-scan ones. This will work, but it is +inefficient: there is no need to create an image-sized coefficient buffer for +single-scan images. Requesting buffered-image mode for such an image wastes +memory. Worse, it can cost time on large images, since the buffered data has +to be swapped out or written to a temporary file. If you are concerned about +maximum performance on baseline JPEG files, you should use buffered-image +mode only when the incoming file actually has multiple scans. This can be +tested by calling jpeg_has_multiple_scans(), which will return a correct +result at any time after jpeg_read_header() completes. + +It is also worth noting that when you use jpeg_consume_input() to let input +processing get ahead of output processing, the resulting pattern of access to +the coefficient buffer is quite nonsequential. It's best to use the memory +manager jmemnobs.c if you can (ie, if you have enough real or virtual main +memory). If not, at least make sure that max_memory_to_use is set as high as +possible. If the JPEG memory manager has to use a temporary file, you will +probably see a lot of disk traffic and poor performance. (This could be +improved with additional work on the memory manager, but we haven't gotten +around to it yet.) + +In some applications it may be convenient to use jpeg_consume_input() for all +input processing, including reading the initial markers; that is, you may +wish to call jpeg_consume_input() instead of jpeg_read_header() during +startup. This works, but note that you must check for JPEG_REACHED_SOS and +JPEG_REACHED_EOI return codes as the equivalent of jpeg_read_header's codes. +Once the first SOS marker has been reached, you must call +jpeg_start_decompress() before jpeg_consume_input() will consume more input; +it'll just keep returning JPEG_REACHED_SOS until you do. If you read a +tables-only file this way, jpeg_consume_input() will return JPEG_REACHED_EOI +without ever returning JPEG_REACHED_SOS; be sure to check for this case. +If this happens, the decompressor will not read any more input until you call +jpeg_abort() to reset it. It is OK to call jpeg_consume_input() even when not +using buffered-image mode, but in that case it's basically a no-op after the +initial markers have been read: it will just return JPEG_SUSPENDED. + + +Abbreviated datastreams and multiple images +------------------------------------------- + +A JPEG compression or decompression object can be reused to process multiple +images. This saves a small amount of time per image by eliminating the +"create" and "destroy" operations, but that isn't the real purpose of the +feature. Rather, reuse of an object provides support for abbreviated JPEG +datastreams. Object reuse can also simplify processing a series of images in +a single input or output file. This section explains these features. + +A JPEG file normally contains several hundred bytes worth of quantization +and Huffman tables. In a situation where many images will be stored or +transmitted with identical tables, this may represent an annoying overhead. +The JPEG standard therefore permits tables to be omitted. The standard +defines three classes of JPEG datastreams: + * "Interchange" datastreams contain an image and all tables needed to decode + the image. These are the usual kind of JPEG file. + * "Abbreviated image" datastreams contain an image, but are missing some or + all of the tables needed to decode that image. + * "Abbreviated table specification" (henceforth "tables-only") datastreams + contain only table specifications. +To decode an abbreviated image, it is necessary to load the missing table(s) +into the decoder beforehand. This can be accomplished by reading a separate +tables-only file. A variant scheme uses a series of images in which the first +image is an interchange (complete) datastream, while subsequent ones are +abbreviated and rely on the tables loaded by the first image. It is assumed +that once the decoder has read a table, it will remember that table until a +new definition for the same table number is encountered. + +It is the application designer's responsibility to figure out how to associate +the correct tables with an abbreviated image. While abbreviated datastreams +can be useful in a closed environment, their use is strongly discouraged in +any situation where data exchange with other applications might be needed. +Caveat designer. + +The JPEG library provides support for reading and writing any combination of +tables-only datastreams and abbreviated images. In both compression and +decompression objects, a quantization or Huffman table will be retained for +the lifetime of the object, unless it is overwritten by a new table definition. + + +To create abbreviated image datastreams, it is only necessary to tell the +compressor not to emit some or all of the tables it is using. Each +quantization and Huffman table struct contains a boolean field "sent_table", +which normally is initialized to FALSE. For each table used by the image, the +header-writing process emits the table and sets sent_table = TRUE unless it is +already TRUE. (In normal usage, this prevents outputting the same table +definition multiple times, as would otherwise occur because the chroma +components typically share tables.) Thus, setting this field to TRUE before +calling jpeg_start_compress() will prevent the table from being written at +all. + +If you want to create a "pure" abbreviated image file containing no tables, +just call "jpeg_suppress_tables(&cinfo, TRUE)" after constructing all the +tables. If you want to emit some but not all tables, you'll need to set the +individual sent_table fields directly. + +To create an abbreviated image, you must also call jpeg_start_compress() +with a second parameter of FALSE, not TRUE. Otherwise jpeg_start_compress() +will force all the sent_table fields to FALSE. (This is a safety feature to +prevent abbreviated images from being created accidentally.) + +To create a tables-only file, perform the same parameter setup that you +normally would, but instead of calling jpeg_start_compress() and so on, call +jpeg_write_tables(&cinfo). This will write an abbreviated datastream +containing only SOI, DQT and/or DHT markers, and EOI. All the quantization +and Huffman tables that are currently defined in the compression object will +be emitted unless their sent_tables flag is already TRUE, and then all the +sent_tables flags will be set TRUE. + +A sure-fire way to create matching tables-only and abbreviated image files +is to proceed as follows: + + create JPEG compression object + set JPEG parameters + set destination to tables-only file + jpeg_write_tables(&cinfo); + set destination to image file + jpeg_start_compress(&cinfo, FALSE); + write data... + jpeg_finish_compress(&cinfo); + +Since the JPEG parameters are not altered between writing the table file and +the abbreviated image file, the same tables are sure to be used. Of course, +you can repeat the jpeg_start_compress() ... jpeg_finish_compress() sequence +many times to produce many abbreviated image files matching the table file. + +You cannot suppress output of the computed Huffman tables when Huffman +optimization is selected. (If you could, there'd be no way to decode the +image...) Generally, you don't want to set optimize_coding = TRUE when +you are trying to produce abbreviated files. + +In some cases you might want to compress an image using tables which are +not stored in the application, but are defined in an interchange or +tables-only file readable by the application. This can be done by setting up +a JPEG decompression object to read the specification file, then copying the +tables into your compression object. See jpeg_copy_critical_parameters() +for an example of copying quantization tables. + + +To read abbreviated image files, you simply need to load the proper tables +into the decompression object before trying to read the abbreviated image. +If the proper tables are stored in the application program, you can just +allocate the table structs and fill in their contents directly. For example, +to load a fixed quantization table into table slot "n": + + if (cinfo.quant_tbl_ptrs[n] == NULL) + cinfo.quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) &cinfo); + quant_ptr = cinfo.quant_tbl_ptrs[n]; /* quant_ptr is JQUANT_TBL* */ + for (i = 0; i < 64; i++) { + /* Qtable[] is desired quantization table, in natural array order */ + quant_ptr->quantval[i] = Qtable[i]; + } + +Code to load a fixed Huffman table is typically (for AC table "n"): + + if (cinfo.ac_huff_tbl_ptrs[n] == NULL) + cinfo.ac_huff_tbl_ptrs[n] = jpeg_alloc_huff_table((j_common_ptr) &cinfo); + huff_ptr = cinfo.ac_huff_tbl_ptrs[n]; /* huff_ptr is JHUFF_TBL* */ + for (i = 1; i <= 16; i++) { + /* counts[i] is number of Huffman codes of length i bits, i=1..16 */ + huff_ptr->bits[i] = counts[i]; + } + for (i = 0; i < 256; i++) { + /* symbols[] is the list of Huffman symbols, in code-length order */ + huff_ptr->huffval[i] = symbols[i]; + } + +(Note that trying to set cinfo.quant_tbl_ptrs[n] to point directly at a +constant JQUANT_TBL object is not safe. If the incoming file happened to +contain a quantization table definition, your master table would get +overwritten! Instead allocate a working table copy and copy the master table +into it, as illustrated above. Ditto for Huffman tables, of course.) + +You might want to read the tables from a tables-only file, rather than +hard-wiring them into your application. The jpeg_read_header() call is +sufficient to read a tables-only file. You must pass a second parameter of +FALSE to indicate that you do not require an image to be present. Thus, the +typical scenario is + + create JPEG decompression object + set source to tables-only file + jpeg_read_header(&cinfo, FALSE); + set source to abbreviated image file + jpeg_read_header(&cinfo, TRUE); + set decompression parameters + jpeg_start_decompress(&cinfo); + read data... + jpeg_finish_decompress(&cinfo); + +In some cases, you may want to read a file without knowing whether it contains +an image or just tables. In that case, pass FALSE and check the return value +from jpeg_read_header(): it will be JPEG_HEADER_OK if an image was found, +JPEG_HEADER_TABLES_ONLY if only tables were found. (A third return value, +JPEG_SUSPENDED, is possible when using a suspending data source manager.) +Note that jpeg_read_header() will not complain if you read an abbreviated +image for which you haven't loaded the missing tables; the missing-table check +occurs later, in jpeg_start_decompress(). + + +It is possible to read a series of images from a single source file by +repeating the jpeg_read_header() ... jpeg_finish_decompress() sequence, +without releasing/recreating the JPEG object or the data source module. +(If you did reinitialize, any partial bufferload left in the data source +buffer at the end of one image would be discarded, causing you to lose the +start of the next image.) When you use this method, stored tables are +automatically carried forward, so some of the images can be abbreviated images +that depend on tables from earlier images. + +If you intend to write a series of images into a single destination file, +you might want to make a specialized data destination module that doesn't +flush the output buffer at term_destination() time. This would speed things +up by some trifling amount. Of course, you'd need to remember to flush the +buffer after the last image. You can make the later images be abbreviated +ones by passing FALSE to jpeg_start_compress(). + + +Special markers +--------------- + +Some applications may need to insert or extract special data in the JPEG +datastream. The JPEG standard provides marker types "COM" (comment) and +"APP0" through "APP15" (application) to hold application-specific data. +Unfortunately, the use of these markers is not specified by the standard. +COM markers are fairly widely used to hold user-supplied text. The JFIF file +format spec uses APP0 markers with specified initial strings to hold certain +data. Adobe applications use APP14 markers beginning with the string "Adobe" +for miscellaneous data. Other APPn markers are rarely seen, but might +contain almost anything. + +If you wish to store user-supplied text, we recommend you use COM markers +and place readable 7-bit ASCII text in them. Newline conventions are not +standardized --- expect to find LF (Unix style), CR/LF (DOS style), or CR +(Mac style). A robust COM reader should be able to cope with random binary +garbage, including nulls, since some applications generate COM markers +containing non-ASCII junk. (But yours should not be one of them.) + +For program-supplied data, use an APPn marker, and be sure to begin it with an +identifying string so that you can tell whether the marker is actually yours. +It's probably best to avoid using APP0 or APP14 for any private markers. +(NOTE: the upcoming SPIFF standard will use APP8 markers; we recommend you +not use APP8 markers for any private purposes, either.) + +Keep in mind that at most 65533 bytes can be put into one marker, but you +can have as many markers as you like. + +By default, the IJG compression library will write a JFIF APP0 marker if the +selected JPEG colorspace is grayscale or YCbCr, or an Adobe APP14 marker if +the selected colorspace is RGB, CMYK, or YCCK. You can disable this, but +we don't recommend it. The decompression library will recognize JFIF and +Adobe markers and will set the JPEG colorspace properly when one is found. + + +You can write special markers immediately following the datastream header by +calling jpeg_write_marker() after jpeg_start_compress() and before the first +call to jpeg_write_scanlines(). When you do this, the markers appear after +the SOI and the JFIF APP0 and Adobe APP14 markers (if written), but before +all else. Specify the marker type parameter as "JPEG_COM" for COM or +"JPEG_APP0 + n" for APPn. (Actually, jpeg_write_marker will let you write +any marker type, but we don't recommend writing any other kinds of marker.) +For example, to write a user comment string pointed to by comment_text: + jpeg_write_marker(cinfo, JPEG_COM, comment_text, strlen(comment_text)); + +If it's not convenient to store all the marker data in memory at once, +you can instead call jpeg_write_m_header() followed by multiple calls to +jpeg_write_m_byte(). If you do it this way, it's your responsibility to +call jpeg_write_m_byte() exactly the number of times given in the length +parameter to jpeg_write_m_header(). (This method lets you empty the +output buffer partway through a marker, which might be important when +using a suspending data destination module. In any case, if you are using +a suspending destination, you should flush its buffer after inserting +any special markers. See "I/O suspension".) + +Or, if you prefer to synthesize the marker byte sequence yourself, +you can just cram it straight into the data destination module. + +If you are writing JFIF 1.02 extension markers (thumbnail images), don't +forget to set cinfo.JFIF_minor_version = 2 so that the encoder will write the +correct JFIF version number in the JFIF header marker. The library's default +is to write version 1.01, but that's wrong if you insert any 1.02 extension +markers. (We could probably get away with just defaulting to 1.02, but there +used to be broken decoders that would complain about unknown minor version +numbers. To reduce compatibility risks it's safest not to write 1.02 unless +you are actually using 1.02 extensions.) + + +When reading, two methods of handling special markers are available: +1. You can ask the library to save the contents of COM and/or APPn markers +into memory, and then examine them at your leisure afterwards. +2. You can supply your own routine to process COM and/or APPn markers +on-the-fly as they are read. +The first method is simpler to use, especially if you are using a suspending +data source; writing a marker processor that copes with input suspension is +not easy (consider what happens if the marker is longer than your available +input buffer). However, the second method conserves memory since the marker +data need not be kept around after it's been processed. + +For either method, you'd normally set up marker handling after creating a +decompression object and before calling jpeg_read_header(), because the +markers of interest will typically be near the head of the file and so will +be scanned by jpeg_read_header. Once you've established a marker handling +method, it will be used for the life of that decompression object +(potentially many datastreams), unless you change it. Marker handling is +determined separately for COM markers and for each APPn marker code. + + +To save the contents of special markers in memory, call + jpeg_save_markers(cinfo, marker_code, length_limit) +where marker_code is the marker type to save, JPEG_COM or JPEG_APP0+n. +(To arrange to save all the special marker types, you need to call this +routine 17 times, for COM and APP0-APP15.) If the incoming marker is longer +than length_limit data bytes, only length_limit bytes will be saved; this +parameter allows you to avoid chewing up memory when you only need to see the +first few bytes of a potentially large marker. If you want to save all the +data, set length_limit to 0xFFFF; that is enough since marker lengths are only +16 bits. As a special case, setting length_limit to 0 prevents that marker +type from being saved at all. (That is the default behavior, in fact.) + +After jpeg_read_header() completes, you can examine the special markers by +following the cinfo->marker_list pointer chain. All the special markers in +the file appear in this list, in order of their occurrence in the file (but +omitting any markers of types you didn't ask for). Both the original data +length and the saved data length are recorded for each list entry; the latter +will not exceed length_limit for the particular marker type. Note that these +lengths exclude the marker length word, whereas the stored representation +within the JPEG file includes it. (Hence the maximum data length is really +only 65533.) + +It is possible that additional special markers appear in the file beyond the +SOS marker at which jpeg_read_header stops; if so, the marker list will be +extended during reading of the rest of the file. This is not expected to be +common, however. If you are short on memory you may want to reset the length +limit to zero for all marker types after finishing jpeg_read_header, to +ensure that the max_memory_to_use setting cannot be exceeded due to addition +of later markers. + +The marker list remains stored until you call jpeg_finish_decompress or +jpeg_abort, at which point the memory is freed and the list is set to empty. +(jpeg_destroy also releases the storage, of course.) + +Note that the library is internally interested in APP0 and APP14 markers; +if you try to set a small nonzero length limit on these types, the library +will silently force the length up to the minimum it wants. (But you can set +a zero length limit to prevent them from being saved at all.) Also, in a +16-bit environment, the maximum length limit may be constrained to less than +65533 by malloc() limitations. It is therefore best not to assume that the +effective length limit is exactly what you set it to be. + + +If you want to supply your own marker-reading routine, you do it by calling +jpeg_set_marker_processor(). A marker processor routine must have the +signature + boolean jpeg_marker_parser_method (j_decompress_ptr cinfo) +Although the marker code is not explicitly passed, the routine can find it +in cinfo->unread_marker. At the time of call, the marker proper has been +read from the data source module. The processor routine is responsible for +reading the marker length word and the remaining parameter bytes, if any. +Return TRUE to indicate success. (FALSE should be returned only if you are +using a suspending data source and it tells you to suspend. See the standard +marker processors in jdmarker.c for appropriate coding methods if you need to +use a suspending data source.) + +If you override the default APP0 or APP14 processors, it is up to you to +recognize JFIF and Adobe markers if you want colorspace recognition to occur +properly. We recommend copying and extending the default processors if you +want to do that. (A better idea is to save these marker types for later +examination by calling jpeg_save_markers(); that method doesn't interfere +with the library's own processing of these markers.) + +jpeg_set_marker_processor() and jpeg_save_markers() are mutually exclusive +--- if you call one it overrides any previous call to the other, for the +particular marker type specified. + +A simple example of an external COM processor can be found in djpeg.c. +Also, see jpegtran.c for an example of using jpeg_save_markers. + + +Raw (downsampled) image data +---------------------------- + +Some applications need to supply already-downsampled image data to the JPEG +compressor, or to receive raw downsampled data from the decompressor. The +library supports this requirement by allowing the application to write or +read raw data, bypassing the normal preprocessing or postprocessing steps. +The interface is different from the standard one and is somewhat harder to +use. If your interest is merely in bypassing color conversion, we recommend +that you use the standard interface and simply set jpeg_color_space = +in_color_space (or jpeg_color_space = out_color_space for decompression). +The mechanism described in this section is necessary only to supply or +receive downsampled image data, in which not all components have the same +dimensions. + + +To compress raw data, you must supply the data in the colorspace to be used +in the JPEG file (please read the earlier section on Special color spaces) +and downsampled to the sampling factors specified in the JPEG parameters. +You must supply the data in the format used internally by the JPEG library, +namely a JSAMPIMAGE array. This is an array of pointers to two-dimensional +arrays, each of type JSAMPARRAY. Each 2-D array holds the values for one +color component. This structure is necessary since the components are of +different sizes. If the image dimensions are not a multiple of the MCU size, +you must also pad the data correctly (usually, this is done by replicating +the last column and/or row). The data must be padded to a multiple of a DCT +block in each component: that is, each downsampled row must contain a +multiple of 8 valid samples, and there must be a multiple of 8 sample rows +for each component. (For applications such as conversion of digital TV +images, the standard image size is usually a multiple of the DCT block size, +so that no padding need actually be done.) + +The procedure for compression of raw data is basically the same as normal +compression, except that you call jpeg_write_raw_data() in place of +jpeg_write_scanlines(). Before calling jpeg_start_compress(), you must do +the following: + * Set cinfo->raw_data_in to TRUE. (It is set FALSE by jpeg_set_defaults().) + This notifies the library that you will be supplying raw data. + * Ensure jpeg_color_space is correct --- an explicit jpeg_set_colorspace() + call is a good idea. Note that since color conversion is bypassed, + in_color_space is ignored, except that jpeg_set_defaults() uses it to + choose the default jpeg_color_space setting. + * Ensure the sampling factors, cinfo->comp_info[i].h_samp_factor and + cinfo->comp_info[i].v_samp_factor, are correct. Since these indicate the + dimensions of the data you are supplying, it's wise to set them + explicitly, rather than assuming the library's defaults are what you want. + +To pass raw data to the library, call jpeg_write_raw_data() in place of +jpeg_write_scanlines(). The two routines work similarly except that +jpeg_write_raw_data takes a JSAMPIMAGE data array rather than JSAMPARRAY. +The scanlines count passed to and returned from jpeg_write_raw_data is +measured in terms of the component with the largest v_samp_factor. + +jpeg_write_raw_data() processes one MCU row per call, which is to say +v_samp_factor*DCTSIZE sample rows of each component. The passed num_lines +value must be at least max_v_samp_factor*DCTSIZE, and the return value will +be exactly that amount (or possibly some multiple of that amount, in future +library versions). This is true even on the last call at the bottom of the +image; don't forget to pad your data as necessary. + +The required dimensions of the supplied data can be computed for each +component as + cinfo->comp_info[i].width_in_blocks*DCTSIZE samples per row + cinfo->comp_info[i].height_in_blocks*DCTSIZE rows in image +after jpeg_start_compress() has initialized those fields. If the valid data +is smaller than this, it must be padded appropriately. For some sampling +factors and image sizes, additional dummy DCT blocks are inserted to make +the image a multiple of the MCU dimensions. The library creates such dummy +blocks itself; it does not read them from your supplied data. Therefore you +need never pad by more than DCTSIZE samples. An example may help here. +Assume 2h2v downsampling of YCbCr data, that is + cinfo->comp_info[0].h_samp_factor = 2 for Y + cinfo->comp_info[0].v_samp_factor = 2 + cinfo->comp_info[1].h_samp_factor = 1 for Cb + cinfo->comp_info[1].v_samp_factor = 1 + cinfo->comp_info[2].h_samp_factor = 1 for Cr + cinfo->comp_info[2].v_samp_factor = 1 +and suppose that the nominal image dimensions (cinfo->image_width and +cinfo->image_height) are 101x101 pixels. Then jpeg_start_compress() will +compute downsampled_width = 101 and width_in_blocks = 13 for Y, +downsampled_width = 51 and width_in_blocks = 7 for Cb and Cr (and the same +for the height fields). You must pad the Y data to at least 13*8 = 104 +columns and rows, the Cb/Cr data to at least 7*8 = 56 columns and rows. The +MCU height is max_v_samp_factor = 2 DCT rows so you must pass at least 16 +scanlines on each call to jpeg_write_raw_data(), which is to say 16 actual +sample rows of Y and 8 each of Cb and Cr. A total of 7 MCU rows are needed, +so you must pass a total of 7*16 = 112 "scanlines". The last DCT block row +of Y data is dummy, so it doesn't matter what you pass for it in the data +arrays, but the scanlines count must total up to 112 so that all of the Cb +and Cr data gets passed. + +Output suspension is supported with raw-data compression: if the data +destination module suspends, jpeg_write_raw_data() will return 0. +In this case the same data rows must be passed again on the next call. + + +Decompression with raw data output implies bypassing all postprocessing: +you cannot ask for rescaling or color quantization, for instance. More +seriously, you must deal with the color space and sampling factors present in +the incoming file. If your application only handles, say, 2h1v YCbCr data, +you must check for and fail on other color spaces or other sampling factors. +The library will not convert to a different color space for you. + +To obtain raw data output, set cinfo->raw_data_out = TRUE before +jpeg_start_decompress() (it is set FALSE by jpeg_read_header()). Be sure to +verify that the color space and sampling factors are ones you can handle. +Then call jpeg_read_raw_data() in place of jpeg_read_scanlines(). The +decompression process is otherwise the same as usual. + +jpeg_read_raw_data() returns one MCU row per call, and thus you must pass a +buffer of at least max_v_samp_factor*DCTSIZE scanlines (scanline counting is +the same as for raw-data compression). The buffer you pass must be large +enough to hold the actual data plus padding to DCT-block boundaries. As with +compression, any entirely dummy DCT blocks are not processed so you need not +allocate space for them, but the total scanline count includes them. The +above example of computing buffer dimensions for raw-data compression is +equally valid for decompression. + +Input suspension is supported with raw-data decompression: if the data source +module suspends, jpeg_read_raw_data() will return 0. You can also use +buffered-image mode to read raw data in multiple passes. + + +Really raw data: DCT coefficients +--------------------------------- + +It is possible to read or write the contents of a JPEG file as raw DCT +coefficients. This facility is mainly intended for use in lossless +transcoding between different JPEG file formats. Other possible applications +include lossless cropping of a JPEG image, lossless reassembly of a +multi-strip or multi-tile TIFF/JPEG file into a single JPEG datastream, etc. + +To read the contents of a JPEG file as DCT coefficients, open the file and do +jpeg_read_header() as usual. But instead of calling jpeg_start_decompress() +and jpeg_read_scanlines(), call jpeg_read_coefficients(). This will read the +entire image into a set of virtual coefficient-block arrays, one array per +component. The return value is a pointer to an array of virtual-array +descriptors. Each virtual array can be accessed directly using the JPEG +memory manager's access_virt_barray method (see Memory management, below, +and also read structure.doc's discussion of virtual array handling). Or, +for simple transcoding to a different JPEG file format, the array list can +just be handed directly to jpeg_write_coefficients(). + +Each block in the block arrays contains quantized coefficient values in +normal array order (not JPEG zigzag order). The block arrays contain only +DCT blocks containing real data; any entirely-dummy blocks added to fill out +interleaved MCUs at the right or bottom edges of the image are discarded +during reading and are not stored in the block arrays. (The size of each +block array can be determined from the width_in_blocks and height_in_blocks +fields of the component's comp_info entry.) This is also the data format +expected by jpeg_write_coefficients(). + +When you are done using the virtual arrays, call jpeg_finish_decompress() +to release the array storage and return the decompression object to an idle +state; or just call jpeg_destroy() if you don't need to reuse the object. + +If you use a suspending data source, jpeg_read_coefficients() will return +NULL if it is forced to suspend; a non-NULL return value indicates successful +completion. You need not test for a NULL return value when using a +non-suspending data source. + +It is also possible to call jpeg_read_coefficients() to obtain access to the +decoder's coefficient arrays during a normal decode cycle in buffered-image +mode. This frammish might be useful for progressively displaying an incoming +image and then re-encoding it without loss. To do this, decode in buffered- +image mode as discussed previously, then call jpeg_read_coefficients() after +the last jpeg_finish_output() call. The arrays will be available for your use +until you call jpeg_finish_decompress(). + + +To write the contents of a JPEG file as DCT coefficients, you must provide +the DCT coefficients stored in virtual block arrays. You can either pass +block arrays read from an input JPEG file by jpeg_read_coefficients(), or +allocate virtual arrays from the JPEG compression object and fill them +yourself. In either case, jpeg_write_coefficients() is substituted for +jpeg_start_compress() and jpeg_write_scanlines(). Thus the sequence is + * Create compression object + * Set all compression parameters as necessary + * Request virtual arrays if needed + * jpeg_write_coefficients() + * jpeg_finish_compress() + * Destroy or re-use compression object +jpeg_write_coefficients() is passed a pointer to an array of virtual block +array descriptors; the number of arrays is equal to cinfo.num_components. + +The virtual arrays need only have been requested, not realized, before +jpeg_write_coefficients() is called. A side-effect of +jpeg_write_coefficients() is to realize any virtual arrays that have been +requested from the compression object's memory manager. Thus, when obtaining +the virtual arrays from the compression object, you should fill the arrays +after calling jpeg_write_coefficients(). The data is actually written out +when you call jpeg_finish_compress(); jpeg_write_coefficients() only writes +the file header. + +When writing raw DCT coefficients, it is crucial that the JPEG quantization +tables and sampling factors match the way the data was encoded, or the +resulting file will be invalid. For transcoding from an existing JPEG file, +we recommend using jpeg_copy_critical_parameters(). This routine initializes +all the compression parameters to default values (like jpeg_set_defaults()), +then copies the critical information from a source decompression object. +The decompression object should have just been used to read the entire +JPEG input file --- that is, it should be awaiting jpeg_finish_decompress(). + +jpeg_write_coefficients() marks all tables stored in the compression object +as needing to be written to the output file (thus, it acts like +jpeg_start_compress(cinfo, TRUE)). This is for safety's sake, to avoid +emitting abbreviated JPEG files by accident. If you really want to emit an +abbreviated JPEG file, call jpeg_suppress_tables(), or set the tables' +individual sent_table flags, between calling jpeg_write_coefficients() and +jpeg_finish_compress(). + + +Progress monitoring +------------------- + +Some applications may need to regain control from the JPEG library every so +often. The typical use of this feature is to produce a percent-done bar or +other progress display. (For a simple example, see cjpeg.c or djpeg.c.) +Although you do get control back frequently during the data-transferring pass +(the jpeg_read_scanlines or jpeg_write_scanlines loop), any additional passes +will occur inside jpeg_finish_compress or jpeg_start_decompress; those +routines may take a long time to execute, and you don't get control back +until they are done. + +You can define a progress-monitor routine which will be called periodically +by the library. No guarantees are made about how often this call will occur, +so we don't recommend you use it for mouse tracking or anything like that. +At present, a call will occur once per MCU row, scanline, or sample row +group, whichever unit is convenient for the current processing mode; so the +wider the image, the longer the time between calls. During the data +transferring pass, only one call occurs per call of jpeg_read_scanlines or +jpeg_write_scanlines, so don't pass a large number of scanlines at once if +you want fine resolution in the progress count. (If you really need to use +the callback mechanism for time-critical tasks like mouse tracking, you could +insert additional calls inside some of the library's inner loops.) + +To establish a progress-monitor callback, create a struct jpeg_progress_mgr, +fill in its progress_monitor field with a pointer to your callback routine, +and set cinfo->progress to point to the struct. The callback will be called +whenever cinfo->progress is non-NULL. (This pointer is set to NULL by +jpeg_create_compress or jpeg_create_decompress; the library will not change +it thereafter. So if you allocate dynamic storage for the progress struct, +make sure it will live as long as the JPEG object does. Allocating from the +JPEG memory manager with lifetime JPOOL_PERMANENT will work nicely.) You +can use the same callback routine for both compression and decompression. + +The jpeg_progress_mgr struct contains four fields which are set by the library: + long pass_counter; /* work units completed in this pass */ + long pass_limit; /* total number of work units in this pass */ + int completed_passes; /* passes completed so far */ + int total_passes; /* total number of passes expected */ +During any one pass, pass_counter increases from 0 up to (not including) +pass_limit; the step size is usually but not necessarily 1. The pass_limit +value may change from one pass to another. The expected total number of +passes is in total_passes, and the number of passes already completed is in +completed_passes. Thus the fraction of work completed may be estimated as + completed_passes + (pass_counter/pass_limit) + -------------------------------------------- + total_passes +ignoring the fact that the passes may not be equal amounts of work. + +When decompressing, pass_limit can even change within a pass, because it +depends on the number of scans in the JPEG file, which isn't always known in +advance. The computed fraction-of-work-done may jump suddenly (if the library +discovers it has overestimated the number of scans) or even decrease (in the +opposite case). It is not wise to put great faith in the work estimate. + +When using the decompressor's buffered-image mode, the progress monitor work +estimate is likely to be completely unhelpful, because the library has no way +to know how many output passes will be demanded of it. Currently, the library +sets total_passes based on the assumption that there will be one more output +pass if the input file end hasn't yet been read (jpeg_input_complete() isn't +TRUE), but no more output passes if the file end has been reached when the +output pass is started. This means that total_passes will rise as additional +output passes are requested. If you have a way of determining the input file +size, estimating progress based on the fraction of the file that's been read +will probably be more useful than using the library's value. + + +Memory management +----------------- + +This section covers some key facts about the JPEG library's built-in memory +manager. For more info, please read structure.doc's section about the memory +manager, and consult the source code if necessary. + +All memory and temporary file allocation within the library is done via the +memory manager. If necessary, you can replace the "back end" of the memory +manager to control allocation yourself (for example, if you don't want the +library to use malloc() and free() for some reason). + +Some data is allocated "permanently" and will not be freed until the JPEG +object is destroyed. Most data is allocated "per image" and is freed by +jpeg_finish_compress, jpeg_finish_decompress, or jpeg_abort. You can call the +memory manager yourself to allocate structures that will automatically be +freed at these times. Typical code for this is + ptr = (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, size); +Use JPOOL_PERMANENT to get storage that lasts as long as the JPEG object. +Use alloc_large instead of alloc_small for anything bigger than a few Kbytes. +There are also alloc_sarray and alloc_barray routines that automatically +build 2-D sample or block arrays. + +The library's minimum space requirements to process an image depend on the +image's width, but not on its height, because the library ordinarily works +with "strip" buffers that are as wide as the image but just a few rows high. +Some operating modes (eg, two-pass color quantization) require full-image +buffers. Such buffers are treated as "virtual arrays": only the current strip +need be in memory, and the rest can be swapped out to a temporary file. + +If you use the simplest memory manager back end (jmemnobs.c), then no +temporary files are used; virtual arrays are simply malloc()'d. Images bigger +than memory can be processed only if your system supports virtual memory. +The other memory manager back ends support temporary files of various flavors +and thus work in machines without virtual memory. They may also be useful on +Unix machines if you need to process images that exceed available swap space. + +When using temporary files, the library will make the in-memory buffers for +its virtual arrays just big enough to stay within a "maximum memory" setting. +Your application can set this limit by setting cinfo->mem->max_memory_to_use +after creating the JPEG object. (Of course, there is still a minimum size for +the buffers, so the max-memory setting is effective only if it is bigger than +the minimum space needed.) If you allocate any large structures yourself, you +must allocate them before jpeg_start_compress() or jpeg_start_decompress() in +order to have them counted against the max memory limit. Also keep in mind +that space allocated with alloc_small() is ignored, on the assumption that +it's too small to be worth worrying about; so a reasonable safety margin +should be left when setting max_memory_to_use. + +If you use the jmemname.c or jmemdos.c memory manager back end, it is +important to clean up the JPEG object properly to ensure that the temporary +files get deleted. (This is especially crucial with jmemdos.c, where the +"temporary files" may be extended-memory segments; if they are not freed, +DOS will require a reboot to recover the memory.) Thus, with these memory +managers, it's a good idea to provide a signal handler that will trap any +early exit from your program. The handler should call either jpeg_abort() +or jpeg_destroy() for any active JPEG objects. A handler is not needed with +jmemnobs.c, and shouldn't be necessary with jmemansi.c or jmemmac.c either, +since the C library is supposed to take care of deleting files made with +tmpfile(). + + +Memory usage +------------ + +Working memory requirements while performing compression or decompression +depend on image dimensions, image characteristics (such as colorspace and +JPEG process), and operating mode (application-selected options). + +As of v6b, the decompressor requires: + 1. About 24K in more-or-less-fixed-size data. This varies a bit depending + on operating mode and image characteristics (particularly color vs. + grayscale), but it doesn't depend on image dimensions. + 2. Strip buffers (of size proportional to the image width) for IDCT and + upsampling results. The worst case for commonly used sampling factors + is about 34 bytes * width in pixels for a color image. A grayscale image + only needs about 8 bytes per pixel column. + 3. A full-image DCT coefficient buffer is needed to decode a multi-scan JPEG + file (including progressive JPEGs), or whenever you select buffered-image + mode. This takes 2 bytes/coefficient. At typical 2x2 sampling, that's + 3 bytes per pixel for a color image. Worst case (1x1 sampling) requires + 6 bytes/pixel. For grayscale, figure 2 bytes/pixel. + 4. To perform 2-pass color quantization, the decompressor also needs a + 128K color lookup table and a full-image pixel buffer (3 bytes/pixel). +This does not count any memory allocated by the application, such as a +buffer to hold the final output image. + +The above figures are valid for 8-bit JPEG data precision and a machine with +32-bit ints. For 12-bit JPEG data, double the size of the strip buffers and +quantization pixel buffer. The "fixed-size" data will be somewhat smaller +with 16-bit ints, larger with 64-bit ints. Also, CMYK or other unusual +color spaces will require different amounts of space. + +The full-image coefficient and pixel buffers, if needed at all, do not +have to be fully RAM resident; you can have the library use temporary +files instead when the total memory usage would exceed a limit you set. +(But if your OS supports virtual memory, it's probably better to just use +jmemnobs and let the OS do the swapping.) + +The compressor's memory requirements are similar, except that it has no need +for color quantization. Also, it needs a full-image DCT coefficient buffer +if Huffman-table optimization is asked for, even if progressive mode is not +requested. + +If you need more detailed information about memory usage in a particular +situation, you can enable the MEM_STATS code in jmemmgr.c. + + +Library compile-time options +---------------------------- + +A number of compile-time options are available by modifying jmorecfg.h. + +The JPEG standard provides for both the baseline 8-bit DCT process and +a 12-bit DCT process. The IJG code supports 12-bit lossy JPEG if you define +BITS_IN_JSAMPLE as 12 rather than 8. Note that this causes JSAMPLE to be +larger than a char, so it affects the surrounding application's image data. +The sample applications cjpeg and djpeg can support 12-bit mode only for PPM +and GIF file formats; you must disable the other file formats to compile a +12-bit cjpeg or djpeg. (install.doc has more information about that.) +At present, a 12-bit library can handle *only* 12-bit images, not both +precisions. (If you need to include both 8- and 12-bit libraries in a single +application, you could probably do it by defining NEED_SHORT_EXTERNAL_NAMES +for just one of the copies. You'd have to access the 8-bit and 12-bit copies +from separate application source files. This is untested ... if you try it, +we'd like to hear whether it works!) + +Note that a 12-bit library always compresses in Huffman optimization mode, +in order to generate valid Huffman tables. This is necessary because our +default Huffman tables only cover 8-bit data. If you need to output 12-bit +files in one pass, you'll have to supply suitable default Huffman tables. +You may also want to supply your own DCT quantization tables; the existing +quality-scaling code has been developed for 8-bit use, and probably doesn't +generate especially good tables for 12-bit. + +The maximum number of components (color channels) in the image is determined +by MAX_COMPONENTS. The JPEG standard allows up to 255 components, but we +expect that few applications will need more than four or so. + +On machines with unusual data type sizes, you may be able to improve +performance or reduce memory space by tweaking the various typedefs in +jmorecfg.h. In particular, on some RISC CPUs, access to arrays of "short"s +is quite slow; consider trading memory for speed by making JCOEF, INT16, and +UINT16 be "int" or "unsigned int". UINT8 is also a candidate to become int. +You probably don't want to make JSAMPLE be int unless you have lots of memory +to burn. + +You can reduce the size of the library by compiling out various optional +functions. To do this, undefine xxx_SUPPORTED symbols as necessary. + +You can also save a few K by not having text error messages in the library; +the standard error message table occupies about 5Kb. This is particularly +reasonable for embedded applications where there's no good way to display +a message anyway. To do this, remove the creation of the message table +(jpeg_std_message_table[]) from jerror.c, and alter format_message to do +something reasonable without it. You could output the numeric value of the +message code number, for example. If you do this, you can also save a couple +more K by modifying the TRACEMSn() macros in jerror.h to expand to nothing; +you don't need trace capability anyway, right? + + +Portability considerations +-------------------------- + +The JPEG library has been written to be extremely portable; the sample +applications cjpeg and djpeg are slightly less so. This section summarizes +the design goals in this area. (If you encounter any bugs that cause the +library to be less portable than is claimed here, we'd appreciate hearing +about them.) + +The code works fine on ANSI C, C++, and pre-ANSI C compilers, using any of +the popular system include file setups, and some not-so-popular ones too. +See install.doc for configuration procedures. + +The code is not dependent on the exact sizes of the C data types. As +distributed, we make the assumptions that + char is at least 8 bits wide + short is at least 16 bits wide + int is at least 16 bits wide + long is at least 32 bits wide +(These are the minimum requirements of the ANSI C standard.) Wider types will +work fine, although memory may be used inefficiently if char is much larger +than 8 bits or short is much bigger than 16 bits. The code should work +equally well with 16- or 32-bit ints. + +In a system where these assumptions are not met, you may be able to make the +code work by modifying the typedefs in jmorecfg.h. However, you will probably +have difficulty if int is less than 16 bits wide, since references to plain +int abound in the code. + +char can be either signed or unsigned, although the code runs faster if an +unsigned char type is available. If char is wider than 8 bits, you will need +to redefine JOCTET and/or provide custom data source/destination managers so +that JOCTET represents exactly 8 bits of data on external storage. + +The JPEG library proper does not assume ASCII representation of characters. +But some of the image file I/O modules in cjpeg/djpeg do have ASCII +dependencies in file-header manipulation; so does cjpeg's select_file_type() +routine. + +The JPEG library does not rely heavily on the C library. In particular, C +stdio is used only by the data source/destination modules and the error +handler, all of which are application-replaceable. (cjpeg/djpeg are more +heavily dependent on stdio.) malloc and free are called only from the memory +manager "back end" module, so you can use a different memory allocator by +replacing that one file. + +The code generally assumes that C names must be unique in the first 15 +characters. However, global function names can be made unique in the +first 6 characters by defining NEED_SHORT_EXTERNAL_NAMES. + +More info about porting the code may be gleaned by reading jconfig.doc, +jmorecfg.h, and jinclude.h. + + +Notes for MS-DOS implementors +----------------------------- + +The IJG code is designed to work efficiently in 80x86 "small" or "medium" +memory models (i.e., data pointers are 16 bits unless explicitly declared +"far"; code pointers can be either size). You may be able to use small +model to compile cjpeg or djpeg by itself, but you will probably have to use +medium model for any larger application. This won't make much difference in +performance. You *will* take a noticeable performance hit if you use a +large-data memory model (perhaps 10%-25%), and you should avoid "huge" model +if at all possible. + +The JPEG library typically needs 2Kb-3Kb of stack space. It will also +malloc about 20K-30K of near heap space while executing (and lots of far +heap, but that doesn't count in this calculation). This figure will vary +depending on selected operating mode, and to a lesser extent on image size. +There is also about 5Kb-6Kb of constant data which will be allocated in the +near data segment (about 4Kb of this is the error message table). +Thus you have perhaps 20K available for other modules' static data and near +heap space before you need to go to a larger memory model. The C library's +static data will account for several K of this, but that still leaves a good +deal for your needs. (If you are tight on space, you could reduce the sizes +of the I/O buffers allocated by jdatasrc.c and jdatadst.c, say from 4K to +1K. Another possibility is to move the error message table to far memory; +this should be doable with only localized hacking on jerror.c.) + +About 2K of the near heap space is "permanent" memory that will not be +released until you destroy the JPEG object. This is only an issue if you +save a JPEG object between compression or decompression operations. + +Far data space may also be a tight resource when you are dealing with large +images. The most memory-intensive case is decompression with two-pass color +quantization, or single-pass quantization to an externally supplied color +map. This requires a 128Kb color lookup table plus strip buffers amounting +to about 40 bytes per column for typical sampling ratios (eg, about 25600 +bytes for a 640-pixel-wide image). You may not be able to process wide +images if you have large data structures of your own. + +Of course, all of these concerns vanish if you use a 32-bit flat-memory-model +compiler, such as DJGPP or Watcom C. We highly recommend flat model if you +can use it; the JPEG library is significantly faster in flat model. diff --git a/src/gdcmjpeg/mangle_jpeg12bits.h b/src/gdcmjpeg/mangle_jpeg12bits.h new file mode 100644 index 00000000..74170655 --- /dev/null +++ b/src/gdcmjpeg/mangle_jpeg12bits.h @@ -0,0 +1,141 @@ +#ifndef gdcm_jpeg12_mangle_h +#define gdcm_jpeg12_mangle_h + +/* + +This header file mangles all symbols exported from the jpeg library. +It is included in all files while building the jpeg library. Due to +namespace pollution, no jpeg headers should be included in .h files in +GDCM. This also allows us to generate two jpeg library (8bits and 12bits). + +The following command was used to obtain the symbol list: + +nm libgdcmjpeg12.a | grep " [R|T] " | colrm 1 11 | sort + +(actually copy/paste from jpeg8bits) +*/ + + + +#define jcopy_block_row gdcm_jpeg12_jcopy_block_row +#define jcopy_sample_rows gdcm_jpeg12_jcopy_sample_rows +#define jdiv_round_up gdcm_jpeg12_jdiv_round_up +#define jinit_1pass_quantizer gdcm_jpeg12_jinit_1pass_quantizer +#define jinit_2pass_quantizer gdcm_jpeg12_jinit_2pass_quantizer +#define jinit_arith_decoder gdcm_jpeg12_jinit_arith_decoder +#define jinit_arith_encoder gdcm_jpeg12_jinit_arith_encoder +#define jinit_c_codec gdcm_jpeg12_jinit_c_codec +#define jinit_c_coef_controller gdcm_jpeg12_jinit_c_coef_controller +#define jinit_c_diff_controller gdcm_jpeg12_jinit_c_diff_controller +#define jinit_c_main_controller gdcm_jpeg12_jinit_c_main_controller +#define jinit_c_master_control gdcm_jpeg12_jinit_c_master_control +#define jinit_c_prep_controller gdcm_jpeg12_jinit_c_prep_controller +#define jinit_c_scaler gdcm_jpeg12_jinit_c_scaler +#define jinit_color_converter gdcm_jpeg12_jinit_color_converter +#define jinit_color_deconverter gdcm_jpeg12_jinit_color_deconverter +#define jinit_compress_master gdcm_jpeg12_jinit_compress_master +#define jinit_d_codec gdcm_jpeg12_jinit_d_codec +#define jinit_d_coef_controller gdcm_jpeg12_jinit_d_coef_controller +#define jinit_d_diff_controller gdcm_jpeg12_jinit_d_diff_controller +#define jinit_d_main_controller gdcm_jpeg12_jinit_d_main_controller +#define jinit_d_post_controller gdcm_jpeg12_jinit_d_post_controller +#define jinit_d_scaler gdcm_jpeg12_jinit_d_scaler +#define jinit_differencer gdcm_jpeg12_jinit_differencer +#define jinit_downsampler gdcm_jpeg12_jinit_downsampler +#define jinit_forward_dct gdcm_jpeg12_jinit_forward_dct +#define jinit_input_controller gdcm_jpeg12_jinit_input_controller +#define jinit_inverse_dct gdcm_jpeg12_jinit_inverse_dct +#define jinit_lhuff_decoder gdcm_jpeg12_jinit_lhuff_decoder +#define jinit_lhuff_encoder gdcm_jpeg12_jinit_lhuff_encoder +#define jinit_lossless_c_codec gdcm_jpeg12_jinit_lossless_c_codec +#define jinit_lossless_d_codec gdcm_jpeg12_jinit_lossless_d_codec +#define jinit_lossy_c_codec gdcm_jpeg12_jinit_lossy_c_codec +#define jinit_lossy_d_codec gdcm_jpeg12_jinit_lossy_d_codec +#define jinit_marker_reader gdcm_jpeg12_jinit_marker_reader +#define jinit_marker_writer gdcm_jpeg12_jinit_marker_writer +#define jinit_master_decompress gdcm_jpeg12_jinit_master_decompress +#define jinit_memory_mgr gdcm_jpeg12_jinit_memory_mgr +#define jinit_merged_upsampler gdcm_jpeg12_jinit_merged_upsampler +#define jinit_phuff_decoder gdcm_jpeg12_jinit_phuff_decoder +#define jinit_phuff_encoder gdcm_jpeg12_jinit_phuff_encoder +#define jinit_shuff_decoder gdcm_jpeg12_jinit_shuff_decoder +#define jinit_shuff_encoder gdcm_jpeg12_jinit_shuff_encoder +#define jinit_undifferencer gdcm_jpeg12_jinit_undifferencer +#define jinit_upsampler gdcm_jpeg12_jinit_upsampler +#define jpeg_CreateCompress gdcm_jpeg12_jpeg_CreateCompress +#define jpeg_CreateDecompress gdcm_jpeg12_jpeg_CreateDecompress +#define jpeg_abort gdcm_jpeg12_jpeg_abort +#define jpeg_abort_compress gdcm_jpeg12_jpeg_abort_compress +#define jpeg_abort_decompress gdcm_jpeg12_jpeg_abort_decompress +#define jpeg_add_quant_table gdcm_jpeg12_jpeg_add_quant_table +#define jpeg_alloc_huff_table gdcm_jpeg12_jpeg_alloc_huff_table +#define jpeg_alloc_quant_table gdcm_jpeg12_jpeg_alloc_quant_table +#define jpeg_calc_output_dimensions gdcm_jpeg12_jpeg_calc_output_dimensions +#define jpeg_consume_input gdcm_jpeg12_jpeg_consume_input +#define jpeg_copy_critical_parameters gdcm_jpeg12_jpeg_copy_critical_parameters +#define jpeg_default_colorspace gdcm_jpeg12_jpeg_default_colorspace +#define jpeg_destroy gdcm_jpeg12_jpeg_destroy +#define jpeg_destroy_compress gdcm_jpeg12_jpeg_destroy_compress +#define jpeg_destroy_decompress gdcm_jpeg12_jpeg_destroy_decompress +#define jpeg_fdct_float gdcm_jpeg12_jpeg_fdct_float +#define jpeg_fdct_ifast gdcm_jpeg12_jpeg_fdct_ifast +#define jpeg_fdct_islow gdcm_jpeg12_jpeg_fdct_islow +#define jpeg_fill_bit_buffer gdcm_jpeg12_jpeg_fill_bit_buffer +#define jpeg_finish_compress gdcm_jpeg12_jpeg_finish_compress +#define jpeg_finish_decompress gdcm_jpeg12_jpeg_finish_decompress +#define jpeg_finish_output gdcm_jpeg12_jpeg_finish_output +#define jpeg_free_large gdcm_jpeg12_jpeg_free_large +#define jpeg_free_small gdcm_jpeg12_jpeg_free_small +#define jpeg_gen_optimal_table gdcm_jpeg12_jpeg_gen_optimal_table +#define jpeg_get_large gdcm_jpeg12_jpeg_get_large +#define jpeg_get_small gdcm_jpeg12_jpeg_get_small +#define jpeg_has_multiple_scans gdcm_jpeg12_jpeg_has_multiple_scans +#define jpeg_huff_decode gdcm_jpeg12_jpeg_huff_decode +#define jpeg_idct_1x1 gdcm_jpeg12_jpeg_idct_1x1 +#define jpeg_idct_2x2 gdcm_jpeg12_jpeg_idct_2x2 +#define jpeg_idct_4x4 gdcm_jpeg12_jpeg_idct_4x4 +#define jpeg_idct_float gdcm_jpeg12_jpeg_idct_float +#define jpeg_idct_ifast gdcm_jpeg12_jpeg_idct_ifast +#define jpeg_idct_islow gdcm_jpeg12_jpeg_idct_islow +#define jpeg_input_complete gdcm_jpeg12_jpeg_input_complete +#define jpeg_make_c_derived_tbl gdcm_jpeg12_jpeg_make_c_derived_tbl +#define jpeg_make_d_derived_tbl gdcm_jpeg12_jpeg_make_d_derived_tbl +#define jpeg_mem_available gdcm_jpeg12_jpeg_mem_available +#define jpeg_mem_init gdcm_jpeg12_jpeg_mem_init +#define jpeg_mem_term gdcm_jpeg12_jpeg_mem_term +#define jpeg_natural_order gdcm_jpeg12_jpeg_natural_order +#define jpeg_new_colormap gdcm_jpeg12_jpeg_new_colormap +#define jpeg_open_backing_store gdcm_jpeg12_jpeg_open_backing_store +#define jpeg_quality_scaling gdcm_jpeg12_jpeg_quality_scaling +#define jpeg_read_coefficients gdcm_jpeg12_jpeg_read_coefficients +#define jpeg_read_header gdcm_jpeg12_jpeg_read_header +#define jpeg_read_raw_data gdcm_jpeg12_jpeg_read_raw_data +#define jpeg_read_scanlines gdcm_jpeg12_jpeg_read_scanlines +#define jpeg_resync_to_restart gdcm_jpeg12_jpeg_resync_to_restart +#define jpeg_save_markers gdcm_jpeg12_jpeg_save_markers +#define jpeg_set_colorspace gdcm_jpeg12_jpeg_set_colorspace +#define jpeg_set_defaults gdcm_jpeg12_jpeg_set_defaults +#define jpeg_set_linear_quality gdcm_jpeg12_jpeg_set_linear_quality +#define jpeg_set_marker_processor gdcm_jpeg12_jpeg_set_marker_processor +#define jpeg_set_quality gdcm_jpeg12_jpeg_set_quality +#define jpeg_simple_lossless gdcm_jpeg12_jpeg_simple_lossless +#define jpeg_simple_progression gdcm_jpeg12_jpeg_simple_progression +#define jpeg_start_compress gdcm_jpeg12_jpeg_start_compress +#define jpeg_start_decompress gdcm_jpeg12_jpeg_start_decompress +#define jpeg_start_output gdcm_jpeg12_jpeg_start_output +#define jpeg_std_error gdcm_jpeg12_jpeg_std_error +#define jpeg_std_message_table gdcm_jpeg12_jpeg_std_message_table +#define jpeg_stdio_dest gdcm_jpeg12_jpeg_stdio_dest +#define jpeg_stdio_src gdcm_jpeg12_jpeg_stdio_src +#define jpeg_suppress_tables gdcm_jpeg12_jpeg_suppress_tables +#define jpeg_write_coefficients gdcm_jpeg12_jpeg_write_coefficients +#define jpeg_write_m_byte gdcm_jpeg12_jpeg_write_m_byte +#define jpeg_write_m_header gdcm_jpeg12_jpeg_write_m_header +#define jpeg_write_marker gdcm_jpeg12_jpeg_write_marker +#define jpeg_write_raw_data gdcm_jpeg12_jpeg_write_raw_data +#define jpeg_write_scanlines gdcm_jpeg12_jpeg_write_scanlines +#define jpeg_write_tables gdcm_jpeg12_jpeg_write_tables +#define jround_up gdcm_jpeg12_jround_up +#define jzero_far gdcm_jpeg12_jzero_far + +#endif diff --git a/src/gdcmjpeg/mangle_jpeg16bits.h b/src/gdcmjpeg/mangle_jpeg16bits.h new file mode 100644 index 00000000..4e5e8dc4 --- /dev/null +++ b/src/gdcmjpeg/mangle_jpeg16bits.h @@ -0,0 +1,141 @@ +#ifndef gdcm_jpeg16_mangle_h +#define gdcm_jpeg16_mangle_h + +/* + +This header file mangles all symbols exported from the jpeg library. +It is included in all files while building the jpeg library. Due to +namespace pollution, no jpeg headers should be included in .h files in +GDCM. This also allows us to generate three jpeg library (8, 12 and 16bits). + +The following command was used to obtain the symbol list: + +nm libgdcmjpeg16.a | grep " [R|T] " | colrm 1 11 | sort + +(actually copy/paste from jpeg8bits) +*/ + + + +#define jcopy_block_row gdcm_jpeg16_jcopy_block_row +#define jcopy_sample_rows gdcm_jpeg16_jcopy_sample_rows +#define jdiv_round_up gdcm_jpeg16_jdiv_round_up +#define jinit_1pass_quantizer gdcm_jpeg16_jinit_1pass_quantizer +#define jinit_2pass_quantizer gdcm_jpeg16_jinit_2pass_quantizer +#define jinit_arith_decoder gdcm_jpeg16_jinit_arith_decoder +#define jinit_arith_encoder gdcm_jpeg16_jinit_arith_encoder +#define jinit_c_codec gdcm_jpeg16_jinit_c_codec +#define jinit_c_coef_controller gdcm_jpeg16_jinit_c_coef_controller +#define jinit_c_diff_controller gdcm_jpeg16_jinit_c_diff_controller +#define jinit_c_main_controller gdcm_jpeg16_jinit_c_main_controller +#define jinit_c_master_control gdcm_jpeg16_jinit_c_master_control +#define jinit_c_prep_controller gdcm_jpeg16_jinit_c_prep_controller +#define jinit_c_scaler gdcm_jpeg16_jinit_c_scaler +#define jinit_color_converter gdcm_jpeg16_jinit_color_converter +#define jinit_color_deconverter gdcm_jpeg16_jinit_color_deconverter +#define jinit_compress_master gdcm_jpeg16_jinit_compress_master +#define jinit_d_codec gdcm_jpeg16_jinit_d_codec +#define jinit_d_coef_controller gdcm_jpeg16_jinit_d_coef_controller +#define jinit_d_diff_controller gdcm_jpeg16_jinit_d_diff_controller +#define jinit_d_main_controller gdcm_jpeg16_jinit_d_main_controller +#define jinit_d_post_controller gdcm_jpeg16_jinit_d_post_controller +#define jinit_d_scaler gdcm_jpeg16_jinit_d_scaler +#define jinit_differencer gdcm_jpeg16_jinit_differencer +#define jinit_downsampler gdcm_jpeg16_jinit_downsampler +#define jinit_forward_dct gdcm_jpeg16_jinit_forward_dct +#define jinit_input_controller gdcm_jpeg16_jinit_input_controller +#define jinit_inverse_dct gdcm_jpeg16_jinit_inverse_dct +#define jinit_lhuff_decoder gdcm_jpeg16_jinit_lhuff_decoder +#define jinit_lhuff_encoder gdcm_jpeg16_jinit_lhuff_encoder +#define jinit_lossless_c_codec gdcm_jpeg16_jinit_lossless_c_codec +#define jinit_lossless_d_codec gdcm_jpeg16_jinit_lossless_d_codec +#define jinit_lossy_c_codec gdcm_jpeg16_jinit_lossy_c_codec +#define jinit_lossy_d_codec gdcm_jpeg16_jinit_lossy_d_codec +#define jinit_marker_reader gdcm_jpeg16_jinit_marker_reader +#define jinit_marker_writer gdcm_jpeg16_jinit_marker_writer +#define jinit_master_decompress gdcm_jpeg16_jinit_master_decompress +#define jinit_memory_mgr gdcm_jpeg16_jinit_memory_mgr +#define jinit_merged_upsampler gdcm_jpeg16_jinit_merged_upsampler +#define jinit_phuff_decoder gdcm_jpeg16_jinit_phuff_decoder +#define jinit_phuff_encoder gdcm_jpeg16_jinit_phuff_encoder +#define jinit_shuff_decoder gdcm_jpeg16_jinit_shuff_decoder +#define jinit_shuff_encoder gdcm_jpeg16_jinit_shuff_encoder +#define jinit_undifferencer gdcm_jpeg16_jinit_undifferencer +#define jinit_upsampler gdcm_jpeg16_jinit_upsampler +#define jpeg_CreateCompress gdcm_jpeg16_jpeg_CreateCompress +#define jpeg_CreateDecompress gdcm_jpeg16_jpeg_CreateDecompress +#define jpeg_abort gdcm_jpeg16_jpeg_abort +#define jpeg_abort_compress gdcm_jpeg16_jpeg_abort_compress +#define jpeg_abort_decompress gdcm_jpeg16_jpeg_abort_decompress +#define jpeg_add_quant_table gdcm_jpeg16_jpeg_add_quant_table +#define jpeg_alloc_huff_table gdcm_jpeg16_jpeg_alloc_huff_table +#define jpeg_alloc_quant_table gdcm_jpeg16_jpeg_alloc_quant_table +#define jpeg_calc_output_dimensions gdcm_jpeg16_jpeg_calc_output_dimensions +#define jpeg_consume_input gdcm_jpeg16_jpeg_consume_input +#define jpeg_copy_critical_parameters gdcm_jpeg16_jpeg_copy_critical_parameters +#define jpeg_default_colorspace gdcm_jpeg16_jpeg_default_colorspace +#define jpeg_destroy gdcm_jpeg16_jpeg_destroy +#define jpeg_destroy_compress gdcm_jpeg16_jpeg_destroy_compress +#define jpeg_destroy_decompress gdcm_jpeg16_jpeg_destroy_decompress +#define jpeg_fdct_float gdcm_jpeg16_jpeg_fdct_float +#define jpeg_fdct_ifast gdcm_jpeg16_jpeg_fdct_ifast +#define jpeg_fdct_islow gdcm_jpeg16_jpeg_fdct_islow +#define jpeg_fill_bit_buffer gdcm_jpeg16_jpeg_fill_bit_buffer +#define jpeg_finish_compress gdcm_jpeg16_jpeg_finish_compress +#define jpeg_finish_decompress gdcm_jpeg16_jpeg_finish_decompress +#define jpeg_finish_output gdcm_jpeg16_jpeg_finish_output +#define jpeg_free_large gdcm_jpeg16_jpeg_free_large +#define jpeg_free_small gdcm_jpeg16_jpeg_free_small +#define jpeg_gen_optimal_table gdcm_jpeg16_jpeg_gen_optimal_table +#define jpeg_get_large gdcm_jpeg16_jpeg_get_large +#define jpeg_get_small gdcm_jpeg16_jpeg_get_small +#define jpeg_has_multiple_scans gdcm_jpeg16_jpeg_has_multiple_scans +#define jpeg_huff_decode gdcm_jpeg16_jpeg_huff_decode +#define jpeg_idct_1x1 gdcm_jpeg16_jpeg_idct_1x1 +#define jpeg_idct_2x2 gdcm_jpeg16_jpeg_idct_2x2 +#define jpeg_idct_4x4 gdcm_jpeg16_jpeg_idct_4x4 +#define jpeg_idct_float gdcm_jpeg16_jpeg_idct_float +#define jpeg_idct_ifast gdcm_jpeg16_jpeg_idct_ifast +#define jpeg_idct_islow gdcm_jpeg16_jpeg_idct_islow +#define jpeg_input_complete gdcm_jpeg16_jpeg_input_complete +#define jpeg_make_c_derived_tbl gdcm_jpeg16_jpeg_make_c_derived_tbl +#define jpeg_make_d_derived_tbl gdcm_jpeg16_jpeg_make_d_derived_tbl +#define jpeg_mem_available gdcm_jpeg16_jpeg_mem_available +#define jpeg_mem_init gdcm_jpeg16_jpeg_mem_init +#define jpeg_mem_term gdcm_jpeg16_jpeg_mem_term +#define jpeg_natural_order gdcm_jpeg16_jpeg_natural_order +#define jpeg_new_colormap gdcm_jpeg16_jpeg_new_colormap +#define jpeg_open_backing_store gdcm_jpeg16_jpeg_open_backing_store +#define jpeg_quality_scaling gdcm_jpeg16_jpeg_quality_scaling +#define jpeg_read_coefficients gdcm_jpeg16_jpeg_read_coefficients +#define jpeg_read_header gdcm_jpeg16_jpeg_read_header +#define jpeg_read_raw_data gdcm_jpeg16_jpeg_read_raw_data +#define jpeg_read_scanlines gdcm_jpeg16_jpeg_read_scanlines +#define jpeg_resync_to_restart gdcm_jpeg16_jpeg_resync_to_restart +#define jpeg_save_markers gdcm_jpeg16_jpeg_save_markers +#define jpeg_set_colorspace gdcm_jpeg16_jpeg_set_colorspace +#define jpeg_set_defaults gdcm_jpeg16_jpeg_set_defaults +#define jpeg_set_linear_quality gdcm_jpeg16_jpeg_set_linear_quality +#define jpeg_set_marker_processor gdcm_jpeg16_jpeg_set_marker_processor +#define jpeg_set_quality gdcm_jpeg16_jpeg_set_quality +#define jpeg_simple_lossless gdcm_jpeg16_jpeg_simple_lossless +#define jpeg_simple_progression gdcm_jpeg16_jpeg_simple_progression +#define jpeg_start_compress gdcm_jpeg16_jpeg_start_compress +#define jpeg_start_decompress gdcm_jpeg16_jpeg_start_decompress +#define jpeg_start_output gdcm_jpeg16_jpeg_start_output +#define jpeg_std_error gdcm_jpeg16_jpeg_std_error +#define jpeg_std_message_table gdcm_jpeg16_jpeg_std_message_table +#define jpeg_stdio_dest gdcm_jpeg16_jpeg_stdio_dest +#define jpeg_stdio_src gdcm_jpeg16_jpeg_stdio_src +#define jpeg_suppress_tables gdcm_jpeg16_jpeg_suppress_tables +#define jpeg_write_coefficients gdcm_jpeg16_jpeg_write_coefficients +#define jpeg_write_m_byte gdcm_jpeg16_jpeg_write_m_byte +#define jpeg_write_m_header gdcm_jpeg16_jpeg_write_m_header +#define jpeg_write_marker gdcm_jpeg16_jpeg_write_marker +#define jpeg_write_raw_data gdcm_jpeg16_jpeg_write_raw_data +#define jpeg_write_scanlines gdcm_jpeg16_jpeg_write_scanlines +#define jpeg_write_tables gdcm_jpeg16_jpeg_write_tables +#define jround_up gdcm_jpeg16_jround_up +#define jzero_far gdcm_jpeg16_jzero_far + +#endif diff --git a/src/gdcmjpeg/mangle_jpeg8bits.h b/src/gdcmjpeg/mangle_jpeg8bits.h new file mode 100644 index 00000000..e5f7f6a5 --- /dev/null +++ b/src/gdcmjpeg/mangle_jpeg8bits.h @@ -0,0 +1,139 @@ +#ifndef gdcm_jpeg8_mangle_h +#define gdcm_jpeg8_mangle_h + +/* + +This header file mangles all symbols exported from the jpeg library. +It is included in all files while building the jpeg library. Due to +namespace pollution, no jpeg headers should be included in .h files in +GDCM. This also allows us to generate two jpeg library (8bits and 12bits). + +The following command was used to obtain the symbol list: + +nm libgdcmjpeg8.a | grep " [R|T] " | colrm 1 11 | sort +*/ + + +#define jcopy_block_row gdcm_jpeg8_jcopy_block_row +#define jcopy_sample_rows gdcm_jpeg8_jcopy_sample_rows +#define jdiv_round_up gdcm_jpeg8_jdiv_round_up +#define jinit_1pass_quantizer gdcm_jpeg8_jinit_1pass_quantizer +#define jinit_2pass_quantizer gdcm_jpeg8_jinit_2pass_quantizer +#define jinit_arith_decoder gdcm_jpeg8_jinit_arith_decoder +#define jinit_arith_encoder gdcm_jpeg8_jinit_arith_encoder +#define jinit_c_codec gdcm_jpeg8_jinit_c_codec +#define jinit_c_coef_controller gdcm_jpeg8_jinit_c_coef_controller +#define jinit_c_diff_controller gdcm_jpeg8_jinit_c_diff_controller +#define jinit_c_main_controller gdcm_jpeg8_jinit_c_main_controller +#define jinit_c_master_control gdcm_jpeg8_jinit_c_master_control +#define jinit_c_prep_controller gdcm_jpeg8_jinit_c_prep_controller +#define jinit_c_scaler gdcm_jpeg8_jinit_c_scaler +#define jinit_color_converter gdcm_jpeg8_jinit_color_converter +#define jinit_color_deconverter gdcm_jpeg8_jinit_color_deconverter +#define jinit_compress_master gdcm_jpeg8_jinit_compress_master +#define jinit_d_codec gdcm_jpeg8_jinit_d_codec +#define jinit_d_coef_controller gdcm_jpeg8_jinit_d_coef_controller +#define jinit_d_diff_controller gdcm_jpeg8_jinit_d_diff_controller +#define jinit_d_main_controller gdcm_jpeg8_jinit_d_main_controller +#define jinit_d_post_controller gdcm_jpeg8_jinit_d_post_controller +#define jinit_d_scaler gdcm_jpeg8_jinit_d_scaler +#define jinit_differencer gdcm_jpeg8_jinit_differencer +#define jinit_downsampler gdcm_jpeg8_jinit_downsampler +#define jinit_forward_dct gdcm_jpeg8_jinit_forward_dct +#define jinit_input_controller gdcm_jpeg8_jinit_input_controller +#define jinit_inverse_dct gdcm_jpeg8_jinit_inverse_dct +#define jinit_lhuff_decoder gdcm_jpeg8_jinit_lhuff_decoder +#define jinit_lhuff_encoder gdcm_jpeg8_jinit_lhuff_encoder +#define jinit_lossless_c_codec gdcm_jpeg8_jinit_lossless_c_codec +#define jinit_lossless_d_codec gdcm_jpeg8_jinit_lossless_d_codec +#define jinit_lossy_c_codec gdcm_jpeg8_jinit_lossy_c_codec +#define jinit_lossy_d_codec gdcm_jpeg8_jinit_lossy_d_codec +#define jinit_marker_reader gdcm_jpeg8_jinit_marker_reader +#define jinit_marker_writer gdcm_jpeg8_jinit_marker_writer +#define jinit_master_decompress gdcm_jpeg8_jinit_master_decompress +#define jinit_memory_mgr gdcm_jpeg8_jinit_memory_mgr +#define jinit_merged_upsampler gdcm_jpeg8_jinit_merged_upsampler +#define jinit_phuff_decoder gdcm_jpeg8_jinit_phuff_decoder +#define jinit_phuff_encoder gdcm_jpeg8_jinit_phuff_encoder +#define jinit_shuff_decoder gdcm_jpeg8_jinit_shuff_decoder +#define jinit_shuff_encoder gdcm_jpeg8_jinit_shuff_encoder +#define jinit_undifferencer gdcm_jpeg8_jinit_undifferencer +#define jinit_upsampler gdcm_jpeg8_jinit_upsampler +#define jpeg_CreateCompress gdcm_jpeg8_jpeg_CreateCompress +#define jpeg_CreateDecompress gdcm_jpeg8_jpeg_CreateDecompress +#define jpeg_abort gdcm_jpeg8_jpeg_abort +#define jpeg_abort_compress gdcm_jpeg8_jpeg_abort_compress +#define jpeg_abort_decompress gdcm_jpeg8_jpeg_abort_decompress +#define jpeg_add_quant_table gdcm_jpeg8_jpeg_add_quant_table +#define jpeg_alloc_huff_table gdcm_jpeg8_jpeg_alloc_huff_table +#define jpeg_alloc_quant_table gdcm_jpeg8_jpeg_alloc_quant_table +#define jpeg_calc_output_dimensions gdcm_jpeg8_jpeg_calc_output_dimensions +#define jpeg_consume_input gdcm_jpeg8_jpeg_consume_input +#define jpeg_copy_critical_parameters gdcm_jpeg8_jpeg_copy_critical_parameters +#define jpeg_default_colorspace gdcm_jpeg8_jpeg_default_colorspace +#define jpeg_destroy gdcm_jpeg8_jpeg_destroy +#define jpeg_destroy_compress gdcm_jpeg8_jpeg_destroy_compress +#define jpeg_destroy_decompress gdcm_jpeg8_jpeg_destroy_decompress +#define jpeg_fdct_float gdcm_jpeg8_jpeg_fdct_float +#define jpeg_fdct_ifast gdcm_jpeg8_jpeg_fdct_ifast +#define jpeg_fdct_islow gdcm_jpeg8_jpeg_fdct_islow +#define jpeg_fill_bit_buffer gdcm_jpeg8_jpeg_fill_bit_buffer +#define jpeg_finish_compress gdcm_jpeg8_jpeg_finish_compress +#define jpeg_finish_decompress gdcm_jpeg8_jpeg_finish_decompress +#define jpeg_finish_output gdcm_jpeg8_jpeg_finish_output +#define jpeg_free_large gdcm_jpeg8_jpeg_free_large +#define jpeg_free_small gdcm_jpeg8_jpeg_free_small +#define jpeg_gen_optimal_table gdcm_jpeg8_jpeg_gen_optimal_table +#define jpeg_get_large gdcm_jpeg8_jpeg_get_large +#define jpeg_get_small gdcm_jpeg8_jpeg_get_small +#define jpeg_has_multiple_scans gdcm_jpeg8_jpeg_has_multiple_scans +#define jpeg_huff_decode gdcm_jpeg8_jpeg_huff_decode +#define jpeg_idct_1x1 gdcm_jpeg8_jpeg_idct_1x1 +#define jpeg_idct_2x2 gdcm_jpeg8_jpeg_idct_2x2 +#define jpeg_idct_4x4 gdcm_jpeg8_jpeg_idct_4x4 +#define jpeg_idct_float gdcm_jpeg8_jpeg_idct_float +#define jpeg_idct_ifast gdcm_jpeg8_jpeg_idct_ifast +#define jpeg_idct_islow gdcm_jpeg8_jpeg_idct_islow +#define jpeg_input_complete gdcm_jpeg8_jpeg_input_complete +#define jpeg_make_c_derived_tbl gdcm_jpeg8_jpeg_make_c_derived_tbl +#define jpeg_make_d_derived_tbl gdcm_jpeg8_jpeg_make_d_derived_tbl +#define jpeg_mem_available gdcm_jpeg8_jpeg_mem_available +#define jpeg_mem_init gdcm_jpeg8_jpeg_mem_init +#define jpeg_mem_term gdcm_jpeg8_jpeg_mem_term +#define jpeg_natural_order gdcm_jpeg8_jpeg_natural_order +#define jpeg_new_colormap gdcm_jpeg8_jpeg_new_colormap +#define jpeg_open_backing_store gdcm_jpeg8_jpeg_open_backing_store +#define jpeg_quality_scaling gdcm_jpeg8_jpeg_quality_scaling +#define jpeg_read_coefficients gdcm_jpeg8_jpeg_read_coefficients +#define jpeg_read_header gdcm_jpeg8_jpeg_read_header +#define jpeg_read_raw_data gdcm_jpeg8_jpeg_read_raw_data +#define jpeg_read_scanlines gdcm_jpeg8_jpeg_read_scanlines +#define jpeg_resync_to_restart gdcm_jpeg8_jpeg_resync_to_restart +#define jpeg_save_markers gdcm_jpeg8_jpeg_save_markers +#define jpeg_set_colorspace gdcm_jpeg8_jpeg_set_colorspace +#define jpeg_set_defaults gdcm_jpeg8_jpeg_set_defaults +#define jpeg_set_linear_quality gdcm_jpeg8_jpeg_set_linear_quality +#define jpeg_set_marker_processor gdcm_jpeg8_jpeg_set_marker_processor +#define jpeg_set_quality gdcm_jpeg8_jpeg_set_quality +#define jpeg_simple_lossless gdcm_jpeg8_jpeg_simple_lossless +#define jpeg_simple_progression gdcm_jpeg8_jpeg_simple_progression +#define jpeg_start_compress gdcm_jpeg8_jpeg_start_compress +#define jpeg_start_decompress gdcm_jpeg8_jpeg_start_decompress +#define jpeg_start_output gdcm_jpeg8_jpeg_start_output +#define jpeg_std_error gdcm_jpeg8_jpeg_std_error +#define jpeg_std_message_table gdcm_jpeg8_jpeg_std_message_table +#define jpeg_stdio_dest gdcm_jpeg8_jpeg_stdio_dest +#define jpeg_stdio_src gdcm_jpeg8_jpeg_stdio_src +#define jpeg_suppress_tables gdcm_jpeg8_jpeg_suppress_tables +#define jpeg_write_coefficients gdcm_jpeg8_jpeg_write_coefficients +#define jpeg_write_m_byte gdcm_jpeg8_jpeg_write_m_byte +#define jpeg_write_m_header gdcm_jpeg8_jpeg_write_m_header +#define jpeg_write_marker gdcm_jpeg8_jpeg_write_marker +#define jpeg_write_raw_data gdcm_jpeg8_jpeg_write_raw_data +#define jpeg_write_scanlines gdcm_jpeg8_jpeg_write_scanlines +#define jpeg_write_tables gdcm_jpeg8_jpeg_write_tables +#define jround_up gdcm_jpeg8_jround_up +#define jzero_far gdcm_jpeg8_jzero_far + + +#endif diff --git a/src/gdcmjpeg/structure.doc b/src/gdcmjpeg/structure.doc new file mode 100644 index 00000000..3d62accf --- /dev/null +++ b/src/gdcmjpeg/structure.doc @@ -0,0 +1,1042 @@ +IJG JPEG LIBRARY: SYSTEM ARCHITECTURE + +Copyright (C) 1991-1995, Thomas G. Lane. +This file is part of the Independent JPEG Group's software. +For conditions of distribution and use, see the accompanying README file. + + +This file provides an overview of the architecture of the IJG JPEG software; +that is, the functions of the various modules in the system and the interfaces +between modules. For more precise details about any data structure or calling +convention, see the include files and comments in the source code. + +We assume that the reader is already somewhat familiar with the JPEG standard. +The README file includes references for learning about JPEG. The file +libjpeg.doc describes the library from the viewpoint of an application +programmer using the library; it's best to read that file before this one. +Also, the file coderules.doc describes the coding style conventions we use. + +In this document, JPEG-specific terminology follows the JPEG standard: + A "component" means a color channel, e.g., Red or Luminance. + A "sample" is a single component value (i.e., one number in the image data). + A "coefficient" is a frequency coefficient (a DCT transform output number). + A "block" is an 8x8 group of samples or coefficients. + A "data unit" is an abstract data type which is either a block for lossy + (DCT-based) codecs or a sample for lossless (predictive) codecs. + An "MCU" (minimum coded unit) is an interleaved set of data units of size + determined by the sampling factors, or a single data unit in a + noninterleaved scan. +We do not use the terms "pixel" and "sample" interchangeably. When we say +pixel, we mean an element of the full-size image, while a sample is an element +of the downsampled image. Thus the number of samples may vary across +components while the number of pixels does not. (This terminology is not used +rigorously throughout the code, but it is used in places where confusion would +otherwise result.) + + +*** System features *** + +The IJG distribution contains two parts: + * A subroutine library for JPEG compression and decompression. + * cjpeg/djpeg, two sample applications that use the library to transform + JFIF JPEG files to and from several other image formats. +cjpeg/djpeg are of no great intellectual complexity: they merely add a simple +command-line user interface and I/O routines for several uncompressed image +formats. This document concentrates on the library itself. + +We desire the library to be capable of supporting all JPEG baseline, extended +sequential, and progressive DCT processes, as well as the lossless (spatial) +process. Hierarchical processes are not supported. + +Within these limits, any set of compression parameters allowed by the JPEG +spec should be readable for decompression. (We can be more restrictive about +what formats we can generate.) Although the system design allows for all +parameter values, some uncommon settings are not yet implemented and may +never be; nonintegral sampling ratios are the prime example. Furthermore, +we treat 8-bit vs. 12-bit data precision as a compile-time switch, not a +run-time option, because most machines can store 8-bit pixels much more +compactly than 12-bit. + +For legal reasons, JPEG arithmetic coding is not currently supported, but +extending the library to include it would be straightforward. + +By itself, the library handles only interchange JPEG datastreams --- in +particular the widely used JFIF file format. The library can be used by +surrounding code to process interchange or abbreviated JPEG datastreams that +are embedded in more complex file formats. (For example, libtiff uses this +library to implement JPEG compression within the TIFF file format.) + +The library includes a substantial amount of code that is not covered by the +JPEG standard but is necessary for typical applications of JPEG. These +functions preprocess the image before JPEG compression or postprocess it after +decompression. They include colorspace conversion, downsampling/upsampling, +and color quantization. This code can be omitted if not needed. + +A wide range of quality vs. speed tradeoffs are possible in JPEG processing, +and even more so in decompression postprocessing. The decompression library +provides multiple implementations that cover most of the useful tradeoffs, +ranging from very-high-quality down to fast-preview operation. On the +compression side we have generally not provided low-quality choices, since +compression is normally less time-critical. It should be understood that the +low-quality modes may not meet the JPEG standard's accuracy requirements; +nonetheless, they are useful for viewers. + + +*** Portability issues *** + +Portability is an essential requirement for the library. The key portability +issues that show up at the level of system architecture are: + +1. Memory usage. We want the code to be able to run on PC-class machines +with limited memory. Images should therefore be processed sequentially (in +strips), to avoid holding the whole image in memory at once. Where a +full-image buffer is necessary, we should be able to use either virtual memory +or temporary files. + +2. Near/far pointer distinction. To run efficiently on 80x86 machines, the +code should distinguish "small" objects (kept in near data space) from +"large" ones (kept in far data space). This is an annoying restriction, but +fortunately it does not impact code quality for less brain-damaged machines, +and the source code clutter turns out to be minimal with sufficient use of +pointer typedefs. + +3. Data precision. We assume that "char" is at least 8 bits, "short" and +"int" at least 16, "long" at least 32. The code will work fine with larger +data sizes, although memory may be used inefficiently in some cases. However, +the JPEG compressed datastream must ultimately appear on external storage as a +sequence of 8-bit bytes if it is to conform to the standard. This may pose a +problem on machines where char is wider than 8 bits. The library represents +compressed data as an array of values of typedef JOCTET. If no data type +exactly 8 bits wide is available, custom data source and data destination +modules must be written to unpack and pack the chosen JOCTET datatype into +8-bit external representation. + + +*** System overview *** + +The compressor and decompressor are each divided into two main sections: +the JPEG compressor or decompressor proper, and the preprocessing or +postprocessing functions. The interface between these two sections is the +image data that the official JPEG spec regards as its input or output: this +data is in the colorspace to be used for compression, and it is downsampled +to the sampling factors to be used. The preprocessing and postprocessing +steps are responsible for converting a normal image representation to or from +this form. (Those few applications that want to deal with YCbCr downsampled +data can skip the preprocessing or postprocessing step.) + +Looking more closely, the compressor library contains the following main +elements: + + Preprocessing: + * Color space conversion (e.g., RGB to YCbCr). + * Edge expansion and downsampling. Optionally, this step can do simple + smoothing --- this is often helpful for low-quality source data. + Lossy JPEG proper: + * MCU assembly, DCT, quantization. + * Entropy coding (sequential or progressive, Huffman or arithmetic). + Lossless JPEG proper: + * Point transform. + * Prediction, differencing. + * Entropy coding (Huffman or arithmetic) + +In addition to these modules we need overall control, marker generation, +and support code (memory management & error handling). There is also a +module responsible for physically writing the output data --- typically +this is just an interface to fwrite(), but some applications may need to +do something else with the data. + +The decompressor library contains the following main elements: + + Lossy JPEG proper: + * Entropy decoding (sequential or progressive, Huffman or arithmetic). + * Dequantization, inverse DCT, MCU disassembly. + Lossless JPEG proper: + * Entropy decoding (Huffman or arithmetic). + * Prediction, undifferencing. + * Point transform, sample size scaling. + Postprocessing: + * Upsampling. Optionally, this step may be able to do more general + rescaling of the image. + * Color space conversion (e.g., YCbCr to RGB). This step may also + provide gamma adjustment [ currently it does not ]. + * Optional color quantization (e.g., reduction to 256 colors). + * Optional color precision reduction (e.g., 24-bit to 15-bit color). + [This feature is not currently implemented.] + +We also need overall control, marker parsing, and a data source module. +The support code (memory management & error handling) can be shared with +the compression half of the library. + +There may be several implementations of each of these elements, particularly +in the decompressor, where a wide range of speed/quality tradeoffs is very +useful. It must be understood that some of the best speedups involve +merging adjacent steps in the pipeline. For example, upsampling, color space +conversion, and color quantization might all be done at once when using a +low-quality ordered-dither technique. The system architecture is designed to +allow such merging where appropriate. + + +Note: it is convenient to regard edge expansion (padding to block boundaries) +as a preprocessing/postprocessing function, even though the JPEG spec includes +it in compression/decompression. We do this because downsampling/upsampling +can be simplified a little if they work on padded data: it's not necessary to +have special cases at the right and bottom edges. Therefore the interface +buffer is always an integral number of blocks wide and high, and we expect +compression preprocessing to pad the source data properly. Padding will occur +only to the next block (8-sample) boundary. In an interleaved-scan situation, +additional dummy blocks may be used to fill out MCUs, but the MCU assembly and +disassembly logic will create or discard these blocks internally. (This is +advantageous for speed reasons, since we avoid DCTing the dummy blocks. +It also permits a small reduction in file size, because the compressor can +choose dummy block contents so as to minimize their size in compressed form. +Finally, it makes the interface buffer specification independent of whether +the file is actually interleaved or not.) Applications that wish to deal +directly with the downsampled data must provide similar buffering and padding +for odd-sized images. + + +*** Poor man's object-oriented programming *** + +It should be clear by now that we have a lot of quasi-independent processing +steps, many of which have several possible behaviors. To avoid cluttering the +code with lots of switch statements, we use a simple form of object-style +programming to separate out the different possibilities. + +For example, two different color quantization algorithms could be implemented +as two separate modules that present the same external interface; at runtime, +the calling code will access the proper module indirectly through an "object". + +We can get the limited features we need while staying within portable C. +The basic tool is a function pointer. An "object" is just a struct +containing one or more function pointer fields, each of which corresponds to +a method name in real object-oriented languages. During initialization we +fill in the function pointers with references to whichever module we have +determined we need to use in this run. Then invocation of the module is done +by indirecting through a function pointer; on most machines this is no more +expensive than a switch statement, which would be the only other way of +making the required run-time choice. The really significant benefit, of +course, is keeping the source code clean and well structured. + +We can also arrange to have private storage that varies between different +implementations of the same kind of object. We do this by making all the +module-specific object structs be separately allocated entities, which will +be accessed via pointers in the master compression or decompression struct. +The "public" fields or methods for a given kind of object are specified by +a commonly known struct. But a module's initialization code can allocate +a larger struct that contains the common struct as its first member, plus +additional private fields. With appropriate pointer casting, the module's +internal functions can access these private fields. (For a simple example, +see jdatadst.c, which implements the external interface specified by struct +jpeg_destination_mgr, but adds extra fields.) + +(Of course this would all be a lot easier if we were using C++, but we are +not yet prepared to assume that everyone has a C++ compiler.) + +An important benefit of this scheme is that it is easy to provide multiple +versions of any method, each tuned to a particular case. While a lot of +precalculation might be done to select an optimal implementation of a method, +the cost per invocation is constant. For example, the upsampling step might +have a "generic" method, plus one or more "hardwired" methods for the most +popular sampling factors; the hardwired methods would be faster because they'd +use straight-line code instead of for-loops. The cost to determine which +method to use is paid only once, at startup, and the selection criteria are +hidden from the callers of the method. + +This plan differs a little bit from usual object-oriented structures, in that +only one instance of each object class will exist during execution. The +reason for having the class structure is that on different runs we may create +different instances (choose to execute different modules). You can think of +the term "method" as denoting the common interface presented by a particular +set of interchangeable functions, and "object" as denoting a group of related +methods, or the total shared interface behavior of a group of modules. + + +*** Overall control structure *** + +We previously mentioned the need for overall control logic in the compression +and decompression libraries. In IJG implementations prior to v5, overall +control was mostly provided by "pipeline control" modules, which proved to be +large, unwieldy, and hard to understand. To improve the situation, the +control logic has been subdivided into multiple modules. The control modules +consist of: + +1. Master control for module selection and initialization. This has two +responsibilities: + + 1A. Startup initialization at the beginning of image processing. + The individual processing modules to be used in this run are selected + and given initialization calls. + + 1B. Per-pass control. This determines how many passes will be performed + and calls each active processing module to configure itself + appropriately at the beginning of each pass. End-of-pass processing, + where necessary, is also invoked from the master control module. + + Method selection is partially distributed, in that a particular processing + module may contain several possible implementations of a particular method, + which it will select among when given its initialization call. The master + control code need only be concerned with decisions that affect more than + one module. + +2. Data buffering control. A separate control module exists for each + inter-processing-step data buffer. This module is responsible for + invoking the processing steps that write or read that data buffer. + +Each buffer controller sees the world as follows: + +input data => processing step A => buffer => processing step B => output data + | | | + ------------------ controller ------------------ + +The controller knows the dataflow requirements of steps A and B: how much data +they want to accept in one chunk and how much they output in one chunk. Its +function is to manage its buffer and call A and B at the proper times. + +A data buffer control module may itself be viewed as a processing step by a +higher-level control module; thus the control modules form a binary tree with +elementary processing steps at the leaves of the tree. + +The control modules are objects. A considerable amount of flexibility can +be had by replacing implementations of a control module. For example: +* Merging of adjacent steps in the pipeline is done by replacing a control + module and its pair of processing-step modules with a single processing- + step module. (Hence the possible merges are determined by the tree of + control modules.) +* In some processing modes, a given interstep buffer need only be a "strip" + buffer large enough to accommodate the desired data chunk sizes. In other + modes, a full-image buffer is needed and several passes are required. + The control module determines which kind of buffer is used and manipulates + virtual array buffers as needed. One or both processing steps may be + unaware of the multi-pass behavior. + +In theory, we might be able to make all of the data buffer controllers +interchangeable and provide just one set of implementations for all. In +practice, each one contains considerable special-case processing for its +particular job. The buffer controller concept should be regarded as an +overall system structuring principle, not as a complete description of the +task performed by any one controller. + + +*** Codec object structure *** + +As noted above, this library supports both the lossy (DCT-based) and lossless +JPEG processes. Because these processes have little in common with one another +(and their implementations share very little code), we need to provide a way to +isloate the underlying JPEG process from the rest of the library. This is +accomplished by introducing an abstract "codec object" which acts a generic +interface to the JPEG (de)compressor proper. + +Using the power of the object-oriented scheme described above, we build the +lossy and lossless modules as two separate implementations of the codec object. +Switching between lossy and lossless processes then becomes as trivial as +assigning the appropriate method pointers during initialization of the library. + + +*** Compression object structure *** + +Here is a sketch of the logical structure of the JPEG compression library: + + |-- Colorspace conversion + |-- Preprocessing controller --| + | |-- Downsampling + | +Main controller --| + | /--> Lossy codec + | / + |-- Compression codec < *OR* + \ + \--> Lossless codec + + +where the lossy codec looks like: + + |-- Forward DCT, quantize +<-- Coefficient controller --| + |-- Entropy encoding + + +and the lossless codec looks like: + + |-- Point transformation + | +<-- Difference controller --|-- Prediction, differencing + | + |-- Lossless entropy encoding + + +This sketch also describes the flow of control (subroutine calls) during +typical image data processing. Each of the components shown in the diagram is +an "object" which may have several different implementations available. One +or more source code files contain the actual implementation(s) of each object. + +The objects shown above are: + +* Main controller: buffer controller for the subsampled-data buffer, which + holds the preprocessed input data. This controller invokes preprocessing to + fill the subsampled-data buffer, and JPEG compression to empty it. There is + usually no need for a full-image buffer here; a strip buffer is adequate. + +* Preprocessing controller: buffer controller for the downsampling input data + buffer, which lies between colorspace conversion and downsampling. Note + that a unified conversion/downsampling module would probably replace this + controller entirely. + +* Colorspace conversion: converts application image data into the desired + JPEG color space; also changes the data from pixel-interleaved layout to + separate component planes. Processes one pixel row at a time. + +* Downsampling: performs reduction of chroma components as required. + Optionally may perform pixel-level smoothing as well. Processes a "row + group" at a time, where a row group is defined as Vmax pixel rows of each + component before downsampling, and Vk sample rows afterwards (remember Vk + differs across components). Some downsampling or smoothing algorithms may + require context rows above and below the current row group; the + preprocessing controller is responsible for supplying these rows via proper + buffering. The downsampler is responsible for edge expansion at the right + edge (i.e., extending each sample row to a multiple of 8 samples); but the + preprocessing controller is responsible for vertical edge expansion (i.e., + duplicating the bottom sample row as needed to make a multiple of 8 rows). + +* Coefficient controller: buffer controller for the DCT-coefficient data. + This controller handles MCU assembly, including insertion of dummy DCT + blocks when needed at the right or bottom edge. When performing + Huffman-code optimization or emitting a multiscan JPEG file, this + controller is responsible for buffering the full image. The equivalent of + one fully interleaved MCU row of subsampled data is processed per call, + even when the JPEG file is noninterleaved. + +* Forward DCT and quantization: Perform DCT, quantize, and emit coefficients. + Works on one or more DCT blocks at a time. (Note: the coefficients are now + emitted in normal array order, which the entropy encoder is expected to + convert to zigzag order as necessary. Prior versions of the IJG code did + the conversion to zigzag order within the quantization step.) + +* Entropy encoding: Perform Huffman or arithmetic entropy coding and emit the + coded data to the data destination module. Works on one MCU per call. + For progressive JPEG, the same DCT blocks are fed to the entropy coder + during each pass, and the coder must emit the appropriate subset of + coefficients. + +* Difference controller: buffer controller for the spatial difference data. + When emitting a multiscan JPEG file, this controller is responsible for + buffering the full image. The equivalent of one fully interleaved MCU row + of subsampled data is processed per call, even when the JPEG file is + noninterleaved. + +* Point transformation: Scale the data down by the point transformation + parameter. + +* Prediction and differencing: Calculate the predictor and subtract it + from the input. Works on one scanline per call. The difference + controller supplies the prior scanline which is used for prediction. + +* Lossless entropy encoding: Perform Huffman or arithmetic entropy coding and + emit the coded data to the data destination module. This module handles MCU + assembly. Works on one MCU-row per call. + +In addition to the above objects, the compression library includes these +objects: + +* Master control: determines the number of passes required, controls overall + and per-pass initialization of the other modules. + +* Marker writing: generates JPEG markers (except for RSTn, which is emitted + by the entropy encoder when needed). + +* Data destination manager: writes the output JPEG datastream to its final + destination (e.g., a file). The destination manager supplied with the + library knows how to write to a stdio stream; for other behaviors, the + surrounding application may provide its own destination manager. + +* Memory manager: allocates and releases memory, controls virtual arrays + (with backing store management, where required). + +* Error handler: performs formatting and output of error and trace messages; + determines handling of nonfatal errors. The surrounding application may + override some or all of this object's methods to change error handling. + +* Progress monitor: supports output of "percent-done" progress reports. + This object represents an optional callback to the surrounding application: + if wanted, it must be supplied by the application. + +The error handler, destination manager, and progress monitor objects are +defined as separate objects in order to simplify application-specific +customization of the JPEG library. A surrounding application may override +individual methods or supply its own all-new implementation of one of these +objects. The object interfaces for these objects are therefore treated as +part of the application interface of the library, whereas the other objects +are internal to the library. + +The error handler and memory manager are shared by JPEG compression and +decompression; the progress monitor, if used, may be shared as well. + + +*** Decompression object structure *** + +Here is a sketch of the logical structure of the JPEG decompression library: + + /--> Lossy codec + / + |-- Decompression codec < *OR* + | \ + | \--> Lossless codec +Main controller --| + | + | |-- Upsampling + |-- Postprocessing controller --| |-- Colorspace conversion + |-- Color quantization + |-- Color precision reduction + + +where the lossy codec looks like: + + |-- Entropy decoding +<-- Coefficient controller --| + |-- Dequantize, Inverse DCT + + +and the lossless codec looks like: + + |-- Lossless entropy decoding + | +<-- Difference controller --|-- Prediction, undifferencing + | + |-- Point transformation, sample size scaling + + +As before, this diagram also represents typical control flow. The objects +shown are: + +* Main controller: buffer controller for the subsampled-data buffer, which + holds the output of JPEG decompression proper. This controller's primary + task is to feed the postprocessing procedure. Some upsampling algorithms + may require context rows above and below the current row group; when this + is true, the main controller is responsible for managing its buffer so as + to make context rows available. In the current design, the main buffer is + always a strip buffer; a full-image buffer is never required. + +* Coefficient controller: buffer controller for the DCT-coefficient data. + This controller handles MCU disassembly, including deletion of any dummy + DCT blocks at the right or bottom edge. When reading a multiscan JPEG + file, this controller is responsible for buffering the full image. + (Buffering DCT coefficients, rather than samples, is necessary to support + progressive JPEG.) The equivalent of one fully interleaved MCU row of + subsampled data is processed per call, even when the source JPEG file is + noninterleaved. + +* Entropy decoding: Read coded data from the data source module and perform + Huffman or arithmetic entropy decoding. Works on one MCU per call. + For progressive JPEG decoding, the coefficient controller supplies the prior + coefficients of each MCU (initially all zeroes), which the entropy decoder + modifies in each scan. + +* Dequantization and inverse DCT: like it says. Note that the coefficients + buffered by the coefficient controller have NOT been dequantized; we + merge dequantization and inverse DCT into a single step for speed reasons. + When scaled-down output is asked for, simplified DCT algorithms may be used + that emit only 1x1, 2x2, or 4x4 samples per DCT block, not the full 8x8. + Works on one DCT block at a time. + +* Difference controller: buffer controller for the spatial difference data. + When reading a multiscan JPEG file, this controller is responsible for + buffering the full image. The equivalent of one fully interleaved MCU row + is processed per call, even when the source JPEG file is noninterleaved. + +* Lossless entropy decoding: Read coded data from the data source module and + perform Huffman or arithmetic entropy decoding. Works on one MCU-row per + call. + +* Prediction and undifferencing: Calculate the predictor and add it to the + decoded difference. Works on one scanline per call. The difference + controller supplies the prior scanline which is used for prediction. + +* Point transform and sample size scaling: Scale the data up by the point + transformation parameter and scale it down to fit into the compiled-in + sample size. + +* Postprocessing controller: buffer controller for the color quantization + input buffer, when quantization is in use. (Without quantization, this + controller just calls the upsampler.) For two-pass quantization, this + controller is responsible for buffering the full-image data. + +* Upsampling: restores chroma components to full size. (May support more + general output rescaling, too. Note that if undersized DCT outputs have + been emitted by the DCT module, this module must adjust so that properly + sized outputs are created.) Works on one row group at a time. This module + also calls the color conversion module, so its top level is effectively a + buffer controller for the upsampling->color conversion buffer. However, in + all but the highest-quality operating modes, upsampling and color + conversion are likely to be merged into a single step. + +* Colorspace conversion: convert from JPEG color space to output color space, + and change data layout from separate component planes to pixel-interleaved. + Works on one pixel row at a time. + +* Color quantization: reduce the data to colormapped form, using either an + externally specified colormap or an internally generated one. This module + is not used for full-color output. Works on one pixel row at a time; may + require two passes to generate a color map. Note that the output will + always be a single component representing colormap indexes. In the current + design, the output values are JSAMPLEs, so an 8-bit compilation cannot + quantize to more than 256 colors. This is unlikely to be a problem in + practice. + +* Color reduction: this module handles color precision reduction, e.g., + generating 15-bit color (5 bits/primary) from JPEG's 24-bit output. + Not quite clear yet how this should be handled... should we merge it with + colorspace conversion??? + +Note that some high-speed operating modes might condense the entire +postprocessing sequence to a single module (upsample, color convert, and +quantize in one step). + +In addition to the above objects, the decompression library includes these +objects: + +* Master control: determines the number of passes required, controls overall + and per-pass initialization of the other modules. This is subdivided into + input and output control: jdinput.c controls only input-side processing, + while jdmaster.c handles overall initialization and output-side control. + +* Marker reading: decodes JPEG markers (except for RSTn). + +* Data source manager: supplies the input JPEG datastream. The source + manager supplied with the library knows how to read from a stdio stream; + for other behaviors, the surrounding application may provide its own source + manager. + +* Memory manager: same as for compression library. + +* Error handler: same as for compression library. + +* Progress monitor: same as for compression library. + +As with compression, the data source manager, error handler, and progress +monitor are candidates for replacement by a surrounding application. + + +*** Decompression input and output separation *** + +To support efficient incremental display of progressive JPEG files, the +decompressor is divided into two sections that can run independently: + +1. Data input includes marker parsing, entropy decoding, and input into the + coefficient controller's DCT coefficient buffer. Note that this + processing is relatively cheap and fast. + +2. Data output reads from the DCT coefficient buffer and performs the IDCT + and all postprocessing steps. + +For a progressive JPEG file, the data input processing is allowed to get +arbitrarily far ahead of the data output processing. (This occurs only +if the application calls jpeg_consume_input(); otherwise input and output +run in lockstep, since the input section is called only when the output +section needs more data.) In this way the application can avoid making +extra display passes when data is arriving faster than the display pass +can run. Furthermore, it is possible to abort an output pass without +losing anything, since the coefficient buffer is read-only as far as the +output section is concerned. See libjpeg.doc for more detail. + +A full-image coefficient array is only created if the JPEG file has multiple +scans (or if the application specifies buffered-image mode anyway). When +reading a single-scan file, the coefficient controller normally creates only +a one-MCU buffer, so input and output processing must run in lockstep in this +case. jpeg_consume_input() is effectively a no-op in this situation. + +The main impact of dividing the decompressor in this fashion is that we must +be very careful with shared variables in the cinfo data structure. Each +variable that can change during the course of decompression must be +classified as belonging to data input or data output, and each section must +look only at its own variables. For example, the data output section may not +depend on any of the variables that describe the current scan in the JPEG +file, because these may change as the data input section advances into a new +scan. + +The progress monitor is (somewhat arbitrarily) defined to treat input of the +file as one pass when buffered-image mode is not used, and to ignore data +input work completely when buffered-image mode is used. Note that the +library has no reliable way to predict the number of passes when dealing +with a progressive JPEG file, nor can it predict the number of output passes +in buffered-image mode. So the work estimate is inherently bogus anyway. + +No comparable division is currently made in the compression library, because +there isn't any real need for it. + + +*** Data formats *** + +Arrays of pixel sample values use the following data structure: + + typedef something JSAMPLE; a pixel component value, 0..MAXJSAMPLE + typedef JSAMPLE *JSAMPROW; ptr to a row of samples + typedef JSAMPROW *JSAMPARRAY; ptr to a list of rows + typedef JSAMPARRAY *JSAMPIMAGE; ptr to a list of color-component arrays + +The basic element type JSAMPLE will typically be one of unsigned char, +(signed) char, or short. Short will be used if samples wider than 8 bits are +to be supported (this is a compile-time option). Otherwise, unsigned char is +used if possible. If the compiler only supports signed chars, then it is +necessary to mask off the value when reading. Thus, all reads of JSAMPLE +values must be coded as "GETJSAMPLE(value)", where the macro will be defined +as "((value) & 0xFF)" on signed-char machines and "((int) (value))" elsewhere. + +With these conventions, JSAMPLE values can be assumed to be >= 0. This helps +simplify correct rounding during downsampling, etc. The JPEG standard's +specification that sample values run from -128..127 is accommodated by +subtracting 128 just as the sample value is copied into the source array for +the DCT step (this will be an array of signed ints). Similarly, during +decompression the output of the IDCT step will be immediately shifted back to +0..255. (NB: different values are required when 12-bit samples are in use. +The code is written in terms of MAXJSAMPLE and CENTERJSAMPLE, which will be +defined as 255 and 128 respectively in an 8-bit implementation, and as 4095 +and 2048 in a 12-bit implementation.) + +We use a pointer per row, rather than a two-dimensional JSAMPLE array. This +choice costs only a small amount of memory and has several benefits: +* Code using the data structure doesn't need to know the allocated width of + the rows. This simplifies edge expansion/compression, since we can work + in an array that's wider than the logical picture width. +* Indexing doesn't require multiplication; this is a performance win on many + machines. +* Arrays with more than 64K total elements can be supported even on machines + where malloc() cannot allocate chunks larger than 64K. +* The rows forming a component array may be allocated at different times + without extra copying. This trick allows some speedups in smoothing steps + that need access to the previous and next rows. + +Note that each color component is stored in a separate array; we don't use the +traditional layout in which the components of a pixel are stored together. +This simplifies coding of modules that work on each component independently, +because they don't need to know how many components there are. Furthermore, +we can read or write each component to a temporary file independently, which +is helpful when dealing with noninterleaved JPEG files. + +In general, a specific sample value is accessed by code such as + GETJSAMPLE(image[colorcomponent][row][col]) +where col is measured from the image left edge, but row is measured from the +first sample row currently in memory. Either of the first two indexings can +be precomputed by copying the relevant pointer. + + +Since most image-processing applications prefer to work on images in which +the components of a pixel are stored together, the data passed to or from the +surrounding application uses the traditional convention: a single pixel is +represented by N consecutive JSAMPLE values, and an image row is an array of +(# of color components)*(image width) JSAMPLEs. One or more rows of data can +be represented by a pointer of type JSAMPARRAY in this scheme. This scheme is +converted to component-wise storage inside the JPEG library. (Applications +that want to skip JPEG preprocessing or postprocessing will have to contend +with component-wise storage.) + + +Arrays of DCT-coefficient values use the following data structure: + + typedef short JCOEF; a 16-bit signed integer + typedef JCOEF JBLOCK[DCTSIZE2]; an 8x8 block of coefficients + typedef JBLOCK *JBLOCKROW; ptr to one horizontal row of 8x8 blocks + typedef JBLOCKROW *JBLOCKARRAY; ptr to a list of such rows + typedef JBLOCKARRAY *JBLOCKIMAGE; ptr to a list of color component arrays + +The underlying type is at least a 16-bit signed integer; while "short" is big +enough on all machines of interest, on some machines it is preferable to use +"int" for speed reasons, despite the storage cost. Coefficients are grouped +into 8x8 blocks (but we always use #defines DCTSIZE and DCTSIZE2 rather than +"8" and "64"). + +The contents of a coefficient block may be in either "natural" or zigzagged +order, and may be true values or divided by the quantization coefficients, +depending on where the block is in the processing pipeline. In the current +library, coefficient blocks are kept in natural order everywhere; the entropy +codecs zigzag or dezigzag the data as it is written or read. The blocks +contain quantized coefficients everywhere outside the DCT/IDCT subsystems. +(This latter decision may need to be revisited to support variable +quantization a la JPEG Part 3.) + +Notice that the allocation unit is now a row of 8x8 blocks, corresponding to +eight rows of samples. Otherwise the structure is much the same as for +samples, and for the same reasons. + +On machines where malloc() can't handle a request bigger than 64Kb, this data +structure limits us to rows of less than 512 JBLOCKs, or a picture width of +4000+ pixels. This seems an acceptable restriction. + + +On 80x86 machines, the bottom-level pointer types (JSAMPROW and JBLOCKROW) +must be declared as "far" pointers, but the upper levels can be "near" +(implying that the pointer lists are allocated in the DS segment). +We use a #define symbol FAR, which expands to the "far" keyword when +compiling on 80x86 machines and to nothing elsewhere. + + +*** Suspendable processing *** + +In some applications it is desirable to use the JPEG library as an +incremental, memory-to-memory filter. In this situation the data source or +destination may be a limited-size buffer, and we can't rely on being able to +empty or refill the buffer at arbitrary times. Instead the application would +like to have control return from the library at buffer overflow/underrun, and +then resume compression or decompression at a later time. + +This scenario is supported for simple cases. (For anything more complex, we +recommend that the application "bite the bullet" and develop real multitasking +capability.) The libjpeg.doc file goes into more detail about the usage and +limitations of this capability; here we address the implications for library +structure. + +The essence of the problem is that the entropy codec (coder or decoder) must +be prepared to stop at arbitrary times. In turn, the controllers that call +the entropy codec must be able to stop before having produced or consumed all +the data that they normally would handle in one call. That part is reasonably +straightforward: we make the controller call interfaces include "progress +counters" which indicate the number of data chunks successfully processed, and +we require callers to test the counter rather than just assume all of the data +was processed. + +Rather than trying to restart at an arbitrary point, the current Huffman +codecs are designed to restart at the beginning of the current MCU after a +suspension due to buffer overflow/underrun. At the start of each call, the +codec's internal state is loaded from permanent storage (in the JPEG object +structures) into local variables. On successful completion of the MCU, the +permanent state is updated. (This copying is not very expensive, and may even +lead to *improved* performance if the local variables can be registerized.) +If a suspension occurs, the codec simply returns without updating the state, +thus effectively reverting to the start of the MCU. Note that this implies +leaving some data unprocessed in the source/destination buffer (ie, the +compressed partial MCU). The data source/destination module interfaces are +specified so as to make this possible. This also implies that the data buffer +must be large enough to hold a worst-case compressed MCU; a couple thousand +bytes should be enough. + +In a successive-approximation AC refinement scan, the progressive Huffman +decoder has to be able to undo assignments of newly nonzero coefficients if it +suspends before the MCU is complete, since decoding requires distinguishing +previously-zero and previously-nonzero coefficients. This is a bit tedious +but probably won't have much effect on performance. Other variants of Huffman +decoding need not worry about this, since they will just store the same values +again if forced to repeat the MCU. + +This approach would probably not work for an arithmetic codec, since its +modifiable state is quite large and couldn't be copied cheaply. Instead it +would have to suspend and resume exactly at the point of the buffer end. + +The JPEG marker reader is designed to cope with suspension at an arbitrary +point. It does so by backing up to the start of the marker parameter segment, +so the data buffer must be big enough to hold the largest marker of interest. +Again, a couple KB should be adequate. (A special "skip" convention is used +to bypass COM and APPn markers, so these can be larger than the buffer size +without causing problems; otherwise a 64K buffer would be needed in the worst +case.) + +The JPEG marker writer currently does *not* cope with suspension. I feel that +this is not necessary; it is much easier simply to require the application to +ensure there is enough buffer space before starting. (An empty 2K buffer is +more than sufficient for the header markers; and ensuring there are a dozen or +two bytes available before calling jpeg_finish_compress() will suffice for the +trailer.) This would not work for writing multi-scan JPEG files, but +we simply do not intend to support that capability with suspension. + + +*** Memory manager services *** + +The JPEG library's memory manager controls allocation and deallocation of +memory, and it manages large "virtual" data arrays on machines where the +operating system does not provide virtual memory. Note that the same +memory manager serves both compression and decompression operations. + +In all cases, allocated objects are tied to a particular compression or +decompression master record, and they will be released when that master +record is destroyed. + +The memory manager does not provide explicit deallocation of objects. +Instead, objects are created in "pools" of free storage, and a whole pool +can be freed at once. This approach helps prevent storage-leak bugs, and +it speeds up operations whenever malloc/free are slow (as they often are). +The pools can be regarded as lifetime identifiers for objects. Two +pools/lifetimes are defined: + * JPOOL_PERMANENT lasts until master record is destroyed + * JPOOL_IMAGE lasts until done with image (JPEG datastream) +Permanent lifetime is used for parameters and tables that should be carried +across from one datastream to another; this includes all application-visible +parameters. Image lifetime is used for everything else. (A third lifetime, +JPOOL_PASS = one processing pass, was originally planned. However it was +dropped as not being worthwhile. The actual usage patterns are such that the +peak memory usage would be about the same anyway; and having per-pass storage +substantially complicates the virtual memory allocation rules --- see below.) + +The memory manager deals with three kinds of object: +1. "Small" objects. Typically these require no more than 10K-20K total. +2. "Large" objects. These may require tens to hundreds of K depending on + image size. Semantically they behave the same as small objects, but we + distinguish them for two reasons: + * On MS-DOS machines, large objects are referenced by FAR pointers, + small objects by NEAR pointers. + * Pool allocation heuristics may differ for large and small objects. + Note that individual "large" objects cannot exceed the size allowed by + type size_t, which may be 64K or less on some machines. +3. "Virtual" objects. These are large 2-D arrays of JSAMPLEs or JBLOCKs + (typically large enough for the entire image being processed). The + memory manager provides stripwise access to these arrays. On machines + without virtual memory, the rest of the array may be swapped out to a + temporary file. + +(Note: JSAMPARRAY and JBLOCKARRAY data structures are a combination of large +objects for the data proper and small objects for the row pointers. For +convenience and speed, the memory manager provides single routines to create +these structures. Similarly, virtual arrays include a small control block +and a JSAMPARRAY or JBLOCKARRAY working buffer, all created with one call.) + +In the present implementation, virtual arrays are only permitted to have image +lifespan. (Permanent lifespan would not be reasonable, and pass lifespan is +not very useful since a virtual array's raison d'etre is to store data for +multiple passes through the image.) We also expect that only "small" objects +will be given permanent lifespan, though this restriction is not required by +the memory manager. + +In a non-virtual-memory machine, some performance benefit can be gained by +making the in-memory buffers for virtual arrays be as large as possible. +(For small images, the buffers might fit entirely in memory, so blind +swapping would be very wasteful.) The memory manager will adjust the height +of the buffers to fit within a prespecified maximum memory usage. In order +to do this in a reasonably optimal fashion, the manager needs to allocate all +of the virtual arrays at once. Therefore, there isn't a one-step allocation +routine for virtual arrays; instead, there is a "request" routine that simply +allocates the control block, and a "realize" routine (called just once) that +determines space allocation and creates all of the actual buffers. The +realize routine must allow for space occupied by non-virtual large objects. +(We don't bother to factor in the space needed for small objects, on the +grounds that it isn't worth the trouble.) + +To support all this, we establish the following protocol for doing business +with the memory manager: + 1. Modules must request virtual arrays (which may have only image lifespan) + during the initial setup phase, i.e., in their jinit_xxx routines. + 2. All "large" objects (including JSAMPARRAYs and JBLOCKARRAYs) must also be + allocated during initial setup. + 3. realize_virt_arrays will be called at the completion of initial setup. + The above conventions ensure that sufficient information is available + for it to choose a good size for virtual array buffers. +Small objects of any lifespan may be allocated at any time. We expect that +the total space used for small objects will be small enough to be negligible +in the realize_virt_arrays computation. + +In a virtual-memory machine, we simply pretend that the available space is +infinite, thus causing realize_virt_arrays to decide that it can allocate all +the virtual arrays as full-size in-memory buffers. The overhead of the +virtual-array access protocol is very small when no swapping occurs. + +A virtual array can be specified to be "pre-zeroed"; when this flag is set, +never-yet-written sections of the array are set to zero before being made +available to the caller. If this flag is not set, never-written sections +of the array contain garbage. (This feature exists primarily because the +equivalent logic would otherwise be needed in jdcoefct.c for progressive +JPEG mode; we may as well make it available for possible other uses.) + +The first write pass on a virtual array is required to occur in top-to-bottom +order; read passes, as well as any write passes after the first one, may +access the array in any order. This restriction exists partly to simplify +the virtual array control logic, and partly because some file systems may not +support seeking beyond the current end-of-file in a temporary file. The main +implication of this restriction is that rearrangement of rows (such as +converting top-to-bottom data order to bottom-to-top) must be handled while +reading data out of the virtual array, not while putting it in. + + +*** Memory manager internal structure *** + +To isolate system dependencies as much as possible, we have broken the +memory manager into two parts. There is a reasonably system-independent +"front end" (jmemmgr.c) and a "back end" that contains only the code +likely to change across systems. All of the memory management methods +outlined above are implemented by the front end. The back end provides +the following routines for use by the front end (none of these routines +are known to the rest of the JPEG code): + +jpeg_mem_init, jpeg_mem_term system-dependent initialization/shutdown + +jpeg_get_small, jpeg_free_small interface to malloc and free library routines + (or their equivalents) + +jpeg_get_large, jpeg_free_large interface to FAR malloc/free in MSDOS machines; + else usually the same as + jpeg_get_small/jpeg_free_small + +jpeg_mem_available estimate available memory + +jpeg_open_backing_store create a backing-store object + +read_backing_store, manipulate a backing-store object +write_backing_store, +close_backing_store + +On some systems there will be more than one type of backing-store object +(specifically, in MS-DOS a backing store file might be an area of extended +memory as well as a disk file). jpeg_open_backing_store is responsible for +choosing how to implement a given object. The read/write/close routines +are method pointers in the structure that describes a given object; this +lets them be different for different object types. + +It may be necessary to ensure that backing store objects are explicitly +released upon abnormal program termination. For example, MS-DOS won't free +extended memory by itself. To support this, we will expect the main program +or surrounding application to arrange to call self_destruct (typically via +jpeg_destroy) upon abnormal termination. This may require a SIGINT signal +handler or equivalent. We don't want to have the back end module install its +own signal handler, because that would pre-empt the surrounding application's +ability to control signal handling. + +The IJG distribution includes several memory manager back end implementations. +Usually the same back end should be suitable for all applications on a given +system, but it is possible for an application to supply its own back end at +need. + + +*** Implications of DNL marker *** + +Some JPEG files may use a DNL marker to postpone definition of the image +height (this would be useful for a fax-like scanner's output, for instance). +In these files the SOF marker claims the image height is 0, and you only +find out the true image height at the end of the first scan. + +We could read these files as follows: +1. Upon seeing zero image height, replace it by 65535 (the maximum allowed). +2. When the DNL is found, update the image height in the global image + descriptor. +This implies that control modules must avoid making copies of the image +height, and must re-test for termination after each MCU row. This would +be easy enough to do. + +In cases where image-size data structures are allocated, this approach will +result in very inefficient use of virtual memory or much-larger-than-necessary +temporary files. This seems acceptable for something that probably won't be a +mainstream usage. People might have to forgo use of memory-hogging options +(such as two-pass color quantization or noninterleaved JPEG files) if they +want efficient conversion of such files. (One could improve efficiency by +demanding a user-supplied upper bound for the height, less than 65536; in most +cases it could be much less.) + +The standard also permits the SOF marker to overestimate the image height, +with a DNL to give the true, smaller height at the end of the first scan. +This would solve the space problems if the overestimate wasn't too great. +However, it implies that you don't even know whether DNL will be used. + +This leads to a couple of very serious objections: +1. Testing for a DNL marker must occur in the inner loop of the decompressor's + Huffman decoder; this implies a speed penalty whether the feature is used + or not. +2. There is no way to hide the last-minute change in image height from an + application using the decoder. Thus *every* application using the IJG + library would suffer a complexity penalty whether it cared about DNL or + not. +We currently do not support DNL because of these problems. + +A different approach is to insist that DNL-using files be preprocessed by a +separate program that reads ahead to the DNL, then goes back and fixes the SOF +marker. This is a much simpler solution and is probably far more efficient. +Even if one wants piped input, buffering the first scan of the JPEG file needs +a lot smaller temp file than is implied by the maximum-height method. For +this approach we'd simply treat DNL as a no-op in the decompressor (at most, +check that it matches the SOF image height). + +We will not worry about making the compressor capable of outputting DNL. +Something similar to the first scheme above could be applied if anyone ever +wants to make that work. diff --git a/src/jdatasrc.cxx b/src/jdatasrc.cxx index e6c64430..336d23a2 100644 --- a/src/jdatasrc.cxx +++ b/src/jdatasrc.cxx @@ -15,6 +15,8 @@ */ /* this is not a core library module, so it doesn't define JPEG_INTERNALS */ +#include +#include /* Expanded data source object for stdio input */ -- 2.45.1