4 * Copyright (C) 1991-1998, Thomas G. Lane.
5 * This file is part of the Independent JPEG Group's software.
6 * For conditions of distribution and use, see the accompanying README file.
8 * This file contains additional configuration options that customize the
9 * JPEG software for special applications or support machine-dependent
10 * optimizations. Most users will not need to touch this file.
14 * Define BITS_IN_JSAMPLE as either
15 * 8 for 8-bit sample values (the usual setting)
16 * 12 for 12-bit sample values
17 * Only 8 and 12 are legal data precisions for lossy JPEG according to the
18 * JPEG standard, and the IJG code does not support anything else!
19 * We do not support run-time selection of data precision, sorry.
22 /*#define BITS_IN_JSAMPLE 8*//* use 8 or 12 (or 16 only for lossless) */
23 #define BITS_IN_JSAMPLE @CMAKE_BITS_IN_JSAMPLE@
26 * Maximum number of components (color channels) allowed in JPEG image.
27 * To meet the letter of the JPEG spec, set this to 255. However, darn
28 * few applications need more than 4 channels (maybe 5 for CMYK + alpha
29 * mask). We recommend 10 as a reasonable compromise; use 4 if you are
30 * really short on memory. (Each allowed component costs a hundred or so
31 * bytes of storage, whether actually used in an image or not.)
34 #define MAX_COMPONENTS 10 /* maximum number of image components */
39 * You may need to change these if you have a machine with unusual data
40 * type sizes; for example, "char" not 8 bits, "short" not 16 bits,
41 * or "long" not 32 bits. We don't care whether "int" is 16 or 32 bits,
42 * but it had better be at least 16.
45 /* Representation of a single sample (pixel element value).
46 * We frequently allocate large arrays of these, so it's important to keep
47 * them small. But if you have memory to burn and access to char or short
48 * arrays is very slow on your hardware, you might want to change these.
51 #if BITS_IN_JSAMPLE == 8
52 /* JSAMPLE should be the smallest type that will hold the values 0..255.
53 * You can use a signed char by having GETJSAMPLE mask it with 0xFF.
56 #ifdef HAVE_UNSIGNED_CHAR
58 typedef unsigned char JSAMPLE;
59 #define GETJSAMPLE(value) ((int) (value))
61 #else /* not HAVE_UNSIGNED_CHAR */
64 #ifdef CHAR_IS_UNSIGNED
65 #define GETJSAMPLE(value) ((int) (value))
67 #define GETJSAMPLE(value) ((int) (value) & 0xFF)
68 #endif /* CHAR_IS_UNSIGNED */
70 #endif /* HAVE_UNSIGNED_CHAR */
72 #define MAXJSAMPLE 255
73 #define CENTERJSAMPLE 128
75 #endif /* BITS_IN_JSAMPLE == 8 */
78 #if BITS_IN_JSAMPLE == 12
79 /* JSAMPLE should be the smallest type that will hold the values 0..4095.
80 * On nearly all machines "short" will do nicely.
83 typedef short JSAMPLE;
84 #define GETJSAMPLE(value) ((int) (value))
86 #define MAXJSAMPLE 4095
87 #define CENTERJSAMPLE 2048
89 #endif /* BITS_IN_JSAMPLE == 12 */
92 #if BITS_IN_JSAMPLE == 16
93 /* JSAMPLE should be the smallest type that will hold the values 0..65535.
94 * You can use a signed short by having GETJSAMPLE mask it with 0xFFFF.
97 #ifdef HAVE_UNSIGNED_SHORT
99 typedef unsigned short JSAMPLE;
100 #define GETJSAMPLE(value) ((int) (value))
102 #else /* not HAVE_UNSIGNED_SHORT */
104 typedef short JSAMPLE;
105 #ifdef SHORT_IS_UNSIGNED
106 #define GETJSAMPLE(value) ((int) (value))
108 #define GETJSAMPLE(value) ((int) (value) & 0xFFFF)
109 #endif /* SHORT_IS_UNSIGNED */
111 #endif /* HAVE_UNSIGNED_SHORT */
113 #define MAXJSAMPLE 65535
114 #define CENTERJSAMPLE 32768
116 #endif /* BITS_IN_JSAMPLE == 16 */
119 /* Representation of a DCT frequency coefficient.
120 * This should be a signed value of at least 16 bits; "short" is usually OK.
121 * Again, we allocate large arrays of these, but you can change to int
122 * if you have memory to burn and "short" is really slow.
128 /* Representation of a spatial difference value.
129 * This should be a signed value of at least 16 bits; int is usually OK.
135 /* Compressed datastreams are represented as arrays of JOCTET.
136 * These must be EXACTLY 8 bits wide, at least once they are written to
137 * external storage. Note that when using the stdio data source/destination
138 * managers, this is also the data type passed to fread/fwrite.
141 #ifdef HAVE_UNSIGNED_CHAR
143 typedef unsigned char JOCTET;
144 #define GETJOCTET(value) (value)
146 #else /* not HAVE_UNSIGNED_CHAR */
149 #ifdef CHAR_IS_UNSIGNED
150 #define GETJOCTET(value) (value)
152 #define GETJOCTET(value) ((value) & 0xFF)
153 #endif /* CHAR_IS_UNSIGNED */
155 #endif /* HAVE_UNSIGNED_CHAR */
158 /* These typedefs are used for various table entries and so forth.
159 * They must be at least as wide as specified; but making them too big
160 * won't cost a huge amount of memory, so we don't provide special
161 * extraction code like we did for JSAMPLE. (In other words, these
162 * typedefs live at a different point on the speed/space tradeoff curve.)
165 /* UINT8 must hold at least the values 0..255. */
167 #ifdef HAVE_UNSIGNED_CHAR
168 typedef unsigned char UINT8;
169 #else /* not HAVE_UNSIGNED_CHAR */
170 #ifdef CHAR_IS_UNSIGNED
172 #else /* not CHAR_IS_UNSIGNED */
174 #endif /* CHAR_IS_UNSIGNED */
175 #endif /* HAVE_UNSIGNED_CHAR */
177 /* UINT16 must hold at least the values 0..65535. */
179 #ifdef HAVE_UNSIGNED_SHORT
180 typedef unsigned short UINT16;
181 #else /* not HAVE_UNSIGNED_SHORT */
182 typedef unsigned int UINT16;
183 #endif /* HAVE_UNSIGNED_SHORT */
185 /* INT16 must hold at least the values -32768..32767. */
187 #ifndef XMD_H /* X11/xmd.h correctly defines INT16 */
191 /* INT32 must hold at least signed 32-bit values. */
192 /* X11/xmd.h and basetsd.h correctly defines INT32 */
194 #if !defined(XMD_H) && !defined(_BASETSD_H_)
198 /* Datatype used for image dimensions. The JPEG standard only supports
199 * images up to 64K*64K due to 16-bit fields in SOF markers. Therefore
200 * "unsigned int" is sufficient on all machines. However, if you need to
201 * handle larger images and you don't mind deviating from the spec, you
202 * can change this datatype.
205 typedef unsigned int JDIMENSION;
207 #define JPEG_MAX_DIMENSION 65500L /* a tad under 64K to prevent overflows */
210 /* These macros are used in all function definitions and extern declarations.
211 * You could modify them if you need to change function linkage conventions;
212 * in particular, you'll need to do that to make the library a Windows DLL.
213 * Another application is to make all functions global for use with debuggers
214 * or code profilers that require it.
218 #cmakedefine JPEGSTATIC
220 /* a function called through method pointers: */
221 #define METHODDEF(type) static type
222 /* a function used only in its module: */
223 #define LOCAL(type) static type
224 /* a function referenced thru EXTERNs: */
225 #if defined( _WIN32 ) && defined (JPEGDLL)
226 #define GLOBAL(type) __declspec(dllexport) type
228 #define GLOBAL(type) type
231 /* a reference to a GLOBAL function: */
232 #if defined(_WIN32) && !defined(JPEGSTATIC)
234 /* Win32, building a dll */
235 #define EXTERN(type) __declspec(dllexport) type
237 /* Win32, not building a dll but using the dll */
238 #define EXTERN(type) __declspec(dllimport) type
241 /* not a Win32 system or building a static Win32 lib */
242 #define EXTERN(type) extern type
246 /* This macro is used to declare a "method", that is, a function pointer.
247 * We want to supply prototype parameters if the compiler can cope.
248 * Note that the arglist parameter must be parenthesized!
249 * Again, you can customize this if you need special linkage keywords.
252 #ifdef HAVE_PROTOTYPES
253 #define JMETHOD(type,methodname,arglist) type (*methodname) arglist
255 #define JMETHOD(type,methodname,arglist) type (*methodname) ()
259 /* Here is the pseudo-keyword for declaring pointers that must be "far"
260 * on 80x86 machines. Most of the specialized coding for 80x86 is handled
261 * by just saying "FAR *" where such a pointer is needed. In a few places
262 * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.
266 #ifdef NEED_FAR_POINTERS
275 * On a few systems, type boolean and/or its values FALSE, TRUE may appear
276 * in standard header files. Or you may have conflicts with application-
277 * specific header files that you want to include together with these files.
278 * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.
284 #ifndef FALSE /* in case these macros already exist */
285 #define FALSE 0 /* values of boolean */
293 * The remaining options affect code selection within the JPEG library,
294 * but they don't need to be visible to most applications using the library.
295 * To minimize application namespace pollution, the symbols won't be
296 * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.
299 #ifdef JPEG_INTERNALS
300 #define JPEG_INTERNAL_OPTIONS
303 #ifdef JPEG_INTERNAL_OPTIONS
307 * These defines indicate whether to include various optional functions.
308 * Undefining some of these symbols will produce a smaller but less capable
309 * library. Note that you can leave certain source files out of the
310 * compilation/linking process if you've #undef'd the corresponding symbols.
311 * (You may HAVE to do that if your compiler doesn't like null source files.)
314 /* Arithmetic coding is unsupported for legal reasons. Complaints to IBM. */
316 /* Capability options common to encoder and decoder: */
318 #define DCT_ISLOW_SUPPORTED /* slow but accurate integer algorithm */
319 #define DCT_IFAST_SUPPORTED /* faster, less accurate integer method */
320 #define DCT_FLOAT_SUPPORTED /* floating-point: accurate, fast on fast HW */
322 /* Encoder capability options: */
324 #undef C_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
325 #define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
326 #define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
327 #define C_LOSSLESS_SUPPORTED /* Lossless JPEG? */
328 #define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */
329 /* Note: if you selected 12-bit data precision, it is dangerous to turn off
330 * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit
331 * precision, so jcshuff.c normally uses entropy optimization to compute
332 * usable tables for higher precision. If you don't want to do optimization,
333 * you'll have to supply different default Huffman tables.
334 * The exact same statements apply for progressive and lossless JPEG:
335 * the default tables don't work for progressive mode or lossless mode.
336 * (This may get fixed, however.)
338 #define INPUT_SMOOTHING_SUPPORTED /* Input image smoothing option? */
340 /* Decoder capability options: */
342 #undef D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */
343 #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */
344 #define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/
345 #define D_LOSSLESS_SUPPORTED /* Lossless JPEG? */
346 #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */
347 #define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */
348 #define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */
349 #undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */
350 #define UPSAMPLE_MERGING_SUPPORTED /* Fast path for sloppy upsampling? */
351 #define QUANT_1PASS_SUPPORTED /* 1-pass color quantization? */
352 #define QUANT_2PASS_SUPPORTED /* 2-pass color quantization? */
354 /* more capability options later, no doubt */
358 * Ordering of RGB data in scanlines passed to or from the application.
359 * If your application wants to deal with data in the order B,G,R, just
360 * change these macros. You can also deal with formats such as R,G,B,X
361 * (one extra byte per pixel) by changing RGB_PIXELSIZE. Note that changing
362 * the offsets will also change the order in which colormap data is organized.
364 * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.
365 * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not
366 * useful if you are using JPEG color spaces other than YCbCr or grayscale.
367 * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE
368 * is not 3 (they don't understand about dummy color components!). So you
369 * can't use color quantization if you change that value.
372 #define RGB_RED 0 /* Offset of Red in an RGB scanline element */
373 #define RGB_GREEN 1 /* Offset of Green */
374 #define RGB_BLUE 2 /* Offset of Blue */
375 #define RGB_PIXELSIZE 3 /* JSAMPLEs per RGB scanline element */
378 /* Definitions for speed-related optimizations. */
381 /* If your compiler supports inline functions, define INLINE
382 * as the inline keyword; otherwise define it as empty.
386 #ifdef __GNUC__ /* for instance, GNU C knows about inline */
387 #define INLINE __inline__
390 #define INLINE /* default is to define it as empty */
395 /* On some machines (notably 68000 series) "int" is 32 bits, but multiplying
396 * two 16-bit shorts is faster than multiplying two ints. Define MULTIPLIER
397 * as short on such a machine. MULTIPLIER must be at least 16 bits wide.
401 #define MULTIPLIER int /* type for fastest integer multiply */
405 /* FAST_FLOAT should be either float or double, whichever is done faster
406 * by your compiler. (Note that this type is only used in the floating point
407 * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)
408 * Typically, float is faster in ANSI C compilers, while double is faster in
409 * pre-ANSI compilers (because they insist on converting to double anyway).
410 * The code below therefore chooses float if we have ANSI-style prototypes.
414 #ifdef HAVE_PROTOTYPES
415 #define FAST_FLOAT float
417 #define FAST_FLOAT double
421 #if defined ( _MSC_VER )
422 #pragma warning ( disable : 4100 )
423 #pragma warning ( disable : 4115 )
424 #pragma warning ( disable : 4127 )
425 #pragma warning ( disable : 4244 )
426 #pragma warning ( disable : 4251 )
427 #pragma warning ( disable : 4267 )
428 #pragma warning ( disable : 4305 )
429 #pragma warning ( disable : 4309 )
430 #pragma warning ( disable : 4706 )
431 #pragma warning ( disable : 4786 )
432 #pragma warning ( disable : 4057 )
433 #pragma warning ( disable : 4189 )
434 #pragma warning ( disable : 4505 )
438 #endif /* JPEG_INTERNAL_OPTIONS */