X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?a=blobdiff_plain;f=src%2FgdcmJpeg.cxx;h=28d0acd17cfabbf2d39082d4363c28a28629fbfd;hb=8ac4df8c7543a827c7b89fc9bbcf86625f3c1afe;hp=4c8f850352334dfeb0d6ed79ef78f024f2ebbfde;hpb=179f2dccd14c31668ef175e8e3373bf8b3121bd1;p=gdcm.git diff --git a/src/gdcmJpeg.cxx b/src/gdcmJpeg.cxx index 4c8f8503..28d0acd1 100644 --- a/src/gdcmJpeg.cxx +++ b/src/gdcmJpeg.cxx @@ -77,10 +77,211 @@ of the uncompressed pixel data from which the compressed data is derived */ extern "C" { -#include "jpeglib.h" +//#include "jpeglib.h" +#include "src/jpeg/libijg8/jconfig.h" +#include "src/jpeg/libijg8/jpeglib.h" + #include } + +/******************** JPEG COMPRESSION SAMPLE INTERFACE *******************/ + +/* This half of the example shows how to feed data into the JPEG compressor. + * We present a minimal version that does not worry about refinements such + * as error recovery (the JPEG code will just exit() if it gets an error). + */ + +/* + * IMAGE DATA FORMATS: + * + * The standard input image format is a rectangular array of pixels, with + * each pixel having the same number of "component" values (color channels). + * Each pixel row is an array of JSAMPLEs (which typically are unsigned chars). + * If you are working with color data, then the color values for each pixel + * must be adjacent in the row; for example, R,G,B,R,G,B,R,G,B,... for 24-bit + * RGB color. + * + * For this example, we'll assume that this data structure matches the way + * our application has stored the image in memory, so we can just pass a + * pointer to our image buffer. In particular, let's say that the image is + * RGB color and is described by: + */ + +// FIXME : JPR + +//extern JSAMPLE * image_buffer; /* Points to large array of R,G,B-order data */ +//extern int image_height; /* Number of rows in image */ +//extern int image_width; /* Number of columns in image */ + + + +/* + * Sample routine for JPEG compression. We assume that the target file name + * and a compression quality factor are passed in. + */ + + /** + * \ingroup gdcmFile + * \brief routine for JPEG decompression + * @param fp pointer to an already open file descriptor + * 8 significant bits per pixel + * @param image_buffer Points to array (of R,G,B-order) data to compress + * @param quality compression quality + * @param image_height Number of rows in image + * @param image_width Number of columns in image + * @return 1 on success, 0 on error + */ + +bool gdcm_write_JPEG_file (FILE* fp, void* im_buf, + int image_width, int image_height, int quality) +{ + + JSAMPLE* image_buffer = (JSAMPLE*) im_buf; + + /* This struct contains the JPEG compression parameters and pointers to + * working space (which is allocated as needed by the JPEG library). + * It is possible to have several such structures, representing multiple + * compression/decompression processes, in existence at once. We refer + * to any one struct (and its associated working data) as a "JPEG object". + */ + struct jpeg_compress_struct cinfo; + /* This struct represents a JPEG error handler. It is declared separately + * because applications often want to supply a specialized error handler + * (see the second half of this file for an example). But here we just + * take the easy way out and use the standard error handler, which will + * print a message on stderr and call exit() if compression fails. + * Note that this struct must live as long as the main JPEG parameter + * struct, to avoid dangling-pointer problems. + */ + struct jpeg_error_mgr jerr; + /* More stuff */ + //FILE* outfile; /* target FILE* / + JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */ + int row_stride; /* physical row width in image buffer */ + + /* Step 1: allocate and initialize JPEG compression object */ + + /* We have to set up the error handler first, in case the initialization + * step fails. (Unlikely, but it could happen if you are out of memory.) + * This routine fills in the contents of struct jerr, and returns jerr's + * address which we place into the link field in cinfo. + */ + cinfo.err = jpeg_std_error(&jerr); + /* Now we can initialize the JPEG compression object. */ + jpeg_create_compress(&cinfo); + + /* Step 2: specify data destination (eg, a file) */ + /* Note: steps 2 and 3 can be done in either order. */ + + /* Here we use the library-supplied code to send compressed data to a + * stdio stream. You can also write your own code to do something else. + * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that + * requires it in order to write binary files. + */ + // if ((outfile = fopen(filename, "wb")) == NULL) { + // fprintf(stderr, "can't open %s\n", filename); + // exit(1); + // + // } + jpeg_stdio_dest(&cinfo, fp); + + /* Step 3: set parameters for compression */ + + /* First we supply a description of the input image. + * Four fields of the cinfo struct must be filled in: + */ + cinfo.image_width = image_width;/* image width and height, in pixels */ + cinfo.image_height = image_height; + cinfo.input_components = 3; /* # of color components per pixel */ + cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ + /* Now use the library's routine to set default compression parameters. + * (You must set at least cinfo.in_color_space before calling this, + * since the defaults depend on the source color space.) + */ + jpeg_set_defaults(&cinfo); + /* Now you can set any non-default parameters you wish to. + * Here we just illustrate the use of quality (quantization table) scaling: + */ + jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */); + + /* Step 4: Start compressor */ + + /* TRUE ensures that we will write a complete interchange-JPEG file. + * Pass TRUE unless you are very sure of what you're doing. + */ + jpeg_start_compress(&cinfo, TRUE); + + /* Step 5: while (scan lines remain to be written) */ + /* jpeg_write_scanlines(...); */ + + /* Here we use the library's state variable cinfo.next_scanline as the + * loop counter, so that we don't have to keep track ourselves. + * To keep things simple, we pass one scanline per call; you can pass + * more if you wish, though. + */ + row_stride = image_width * 3;/* JSAMPLEs per row in image_buffer */ + + while (cinfo.next_scanline < cinfo.image_height) { + /* jpeg_write_scanlines expects an array of pointers to scanlines. + * Here the array is only one element long, but you could pass + * more than one scanline at a time if that's more convenient. + */ + row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride]; + + (void) jpeg_write_scanlines(&cinfo, row_pointer, 1); + } + + /* Step 6: Finish compression */ + + jpeg_finish_compress(&cinfo); + + /* After finish_compress, we can close the output file. */ + + // fclose(fp); --> the caller will close (multiframe treatement) + + /* Step 7: release JPEG compression object */ + + /* This is an important step since it will release a good deal of memory. */ + jpeg_destroy_compress(&cinfo); + + /* And we're done! */ + + return true; //??? +} + + + +/* + * SOME FINE POINTS: + * + * In the above loop, we ignored the return value of jpeg_write_scanlines, + * which is the number of scanlines actually written. We could get away + * with this because we were only relying on the value of cinfo.next_scanline, + * which will be incremented correctly. If you maintain additional loop + * variables then you should be careful to increment them properly. + * Actually, for output to a stdio stream you needn't worry, because + * then jpeg_write_scanlines will write all the lines passed (or else exit + * with a fatal error). Partial writes can only occur if you use a data + * destination module that can demand suspension of the compressor. + * (If you don't know what that's for, you don't need it.) + * + * If the compressor requires full-image buffers (for entropy-coding + * optimization or a multi-scan JPEG file), it will create temporary + * files for anything that doesn't fit within the maximum-memory setting. + * (Note that temp files are NOT needed if you use the default parameters.) + * On some systems you may need to set up a signal handler to ensure that + * temporary files are deleted if the program is interrupted. See libjpeg.doc. + * + * Scanlines MUST be supplied in top-to-bottom order if you want your JPEG + * files to be compatible with everyone else's. If you cannot readily read + * your data in that order, you'll need an intermediate array to hold the + * image. See rdtarga.c or rdbmp.c for examples of handling bottom-to-top + * source data using the JPEG code's internal virtual-array mechanisms. + */ + + + /******************** JPEG DECOMPRESSION SAMPLE INTERFACE *******************/ /* This half of the example shows how to read data from the JPEG decompressor. @@ -127,7 +328,7 @@ struct my_error_mgr { }; //----------------------------------------------------------------------------- -typedef struct my_error_mgr * my_error_ptr; +typedef struct my_error_mgr* my_error_ptr; /* * Here's the routine that will replace the standard error_exit method: @@ -159,8 +360,8 @@ METHODDEF(void) my_error_exit (j_common_ptr cinfo) { * @return 1 on success, 0 on error */ -bool gdcmFile::gdcm_read_JPEG_file (FILE *fp,void * image_buffer) { - char *pimage; +bool gdcmFile::gdcm_read_JPEG_file (FILE* fp, void* image_buffer) { + char* pimage; /* This struct contains the JPEG decompression parameters and pointers to * working space (which is allocated as needed by the JPEG library). @@ -194,7 +395,7 @@ bool gdcmFile::gdcm_read_JPEG_file (FILE *fp,void * image_buffer) { int row_stride;/* physical row width in output buffer */ #ifdef GDCM_JPG_DEBUG - printf("entree dans gdcmFile::gdcm_read_JPEG_file12, depuis gdcmJpeg\n"); + printf("entree dans gdcmFile::gdcm_read_JPEG_file (i.e. 8), depuis gdcmJpeg\n"); #endif //GDCM_JPG_DEBUG /* In this example we want to open the input file before doing anything else, @@ -375,6 +576,7 @@ bool gdcmFile::gdcm_read_JPEG_file (FILE *fp,void * image_buffer) { return(true); } + /* * SOME FINE POINTS: *