/* * File: genJPEGStrips.c * Purpose: this file implements routines to compress and decompress jpeg image files. It utilizes * libjpeg to do the "work". */ #include //#include #include #include "common_defines.h" #include "PCLmGenerator.h" /* * Include file for users of JPEG library. * You will need to have included system headers that define at least * the typedefs FILE and size_t before you can include jpeglib.h. * (stdio.h is sufficient on ANSI-conforming systems.) * You may also wish to include "jerror.h". */ extern "C" { #include "jpeglib.h" } /* * is used for the optional error recovery mechanism shown in * the second part of the example. */ #include #include #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: */ /* typedef char JSAMPLE;*/ //Sanjay:Earlier following 3 lines were commented int image_width; int image_height; int image_numComponents; //extern int DebugIt; //extern int DebugIt2; int DebugIt = false; int DebugIt2 = false; unsigned char *myImageBuffer=NULL; typedef struct jpeg_decompress_struct cinfoCompressType; // int put_scanline_someplace(jpeg_decompress_struct *cinfo, char *buffer, int physicalWidth) int put_scanline_someplace(cinfoCompressType *cinfo, char *buffer, int physicalWidth) { static unsigned char *destBuffer; if(myImageBuffer==NULL) { int width =cinfo->image_width; int height =cinfo->image_height; int numComponents =(int)cinfo->num_components; int allocSize =width*height*numComponents; #if 0 printf("Image Stats\n"); printf(" ImageWidth=%d\n",width); printf(" ImageHeight=%d\n",height); printf(" ImageNumComponents=%d\n",numComponents); // printf(" ImageColorSpace=%d\n"); //printf(" ImageScale=%d\n",scale); #endif myImageBuffer=(unsigned char*)malloc(allocSize*2); //if(DebugIt2) //Sanjay:Earlier commented { //printf("myImageBuffer: allocated; size=%d\n",allocSize*2); } if(!myImageBuffer) { printf("Could not allocate enough memory for source JPEG file; exiting\n"); exit(-1); } memset(myImageBuffer,0x0,allocSize); //Sanjay: Earlier following 3 lines were commented image_width=width; image_height=height; image_numComponents=numComponents; destBuffer=myImageBuffer; } memcpy(destBuffer,buffer,physicalWidth); destBuffer+=physicalWidth; return(1); } /* Sample routine for JPEG compression. We assume that the target file name * and a compression quality factor are passed in. */ /* setup the buffer but we did that in the calling function */ void init_buffer(jpeg_compress_struct* cinfo) {} /* what to do when the buffer is full; this should almost never * happen since we allocated our buffer to be big to start with */ boolean empty_buffer(jpeg_compress_struct* cinfo) { return TRUE; } /* finalize the buffer and do any cleanup stuff */ void term_buffer(jpeg_compress_struct* cinfo) {} GLOBAL(void) write_JPEG_Buff (ubyte * buffPtr, int quality, int image_width, int image_height, JSAMPLE *imageBuffer, int resolution, colorSpaceDisposition destCS, int *numCompBytes) { /* 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; struct jpeg_destination_mgr dmgr; /* 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 */ JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */ int row_stride; /* physical row width in image buffer */ /* here is the magic */ dmgr.init_destination = init_buffer; dmgr.empty_output_buffer = empty_buffer; dmgr.term_destination = term_buffer; dmgr.next_output_byte = (JOCTET *)buffPtr; dmgr.free_in_buffer = image_width * image_height * 3; /* 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); cinfo.dest = &dmgr; /* Step 2: specify data destination (eg, a file) */ /* Note: steps 2 and 3 can be done in either order. */ /* 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 */ if(destCS==deviceRGB || destCS==adobeRGB) { cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ cinfo.jpeg_color_space = JCS_RGB; /* colorspace of input image */ cinfo.input_components = 3; } else { cinfo.in_color_space = JCS_GRAYSCALE; /* colorspace of input image */ cinfo.jpeg_color_space = JCS_GRAYSCALE; /* colorspace of input image */ cinfo.input_components = 1; } /* 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); if (destCS==deviceRGB || destCS==adobeRGB) { jpeg_set_colorspace (&cinfo,JCS_RGB); } /* 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 */); /* Set the density so that the JFIF header has the correct settings */ cinfo.density_unit=1; /* 1=dots-per-inch, 2=dots per cm */ cinfo.X_density=(UINT16)resolution; cinfo.Y_density=(UINT16)resolution; /* set the rows/columns setting to reflect the resolution */ /* MCU = Minimum Coded Unit */ #if 0 cinfo.MCUs_per_row =image_width; cinfo.MCU_rows_in_scan=image_height; #else //cinfo.MCUs_per_row =16; cinfo.MCUs_per_row =image_width; // cinfo.MCU_rows_in_scan=16; cinfo.MCU_rows_in_scan=image_height; #endif if(DebugIt2) { printf("cinfo:\n"); printf(" width=%d\n",cinfo.image_width); printf(" height=%d\n",cinfo.image_height); printf(" input_components=%d\n",cinfo.input_components); printf(" input_in_color_space=%d\n",cinfo.in_color_space); printf(" input_out_color_space=%d\n",cinfo.jpeg_color_space); printf(" num_components=%d\n",cinfo.num_components); printf(" X_density=%d\n",cinfo.X_density); printf(" Y_density=%d\n",cinfo.Y_density); printf(" MCUs_per_row=%d\n",cinfo.MCUs_per_row); printf(" MCUs_rows_in_scan=%d\n",cinfo.MCU_rows_in_scan); } /* 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 * cinfo.input_components; /* JSAMPLEs per row in , imageBuffer */ 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. */ //printf("image_height=%d, image_width=%d\n",cinfo.image_height, cinfo.image_width); row_pointer[0] = & imageBuffer[cinfo.next_scanline * row_stride]; /*if(DebugIt) { printf("putting JPEG scanline at address 0x%x\n",imageBuffer[cinfo.next_scanline * row_stride]); JSAMPLE *i,*j; i=(JSAMPLE*)(imageBuffer[cinfo.next_scanline * row_stride]); j=(JSAMPLE*)(imageBuffer); printf(" offset=%ld\n",i-j); }*/ (void) jpeg_write_scanlines(&cinfo, row_pointer, 1); } /* Step 6: Finish compression */ jpeg_finish_compress(&cinfo); /* Step 7: release JPEG compression object */ /* This is an important step since it will release a good deal of memory. */ jpeg_destroy_compress(&cinfo); *numCompBytes=(int)(cinfo.dest->next_output_byte - buffPtr); /* And we're done! */ } #if 0 GLOBAL(void) write_JPEG_file (char * filename, int quality, int image_width, int image_height, JSAMPLE *imageBuffer, int resolution, colorSpaceEnum destCS) { /* 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, outfile); /* 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 */ #if 0 if(destCS==RGB) cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ else cinfo.in_color_space = JCS_GRAYSCALE; /* colorspace of input image */ #endif if(destCS==RGB) { cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ cinfo.jpeg_color_space = JCS_RGB; /* colorspace of input image */ cinfo.input_components=3; } else { cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ cinfo.jpeg_color_space = JCS_GRAYSCALE; /* colorspace of input image */ cinfo.input_components=3; } /* 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); if(DebugIt) { printf("cinfo:\n"); printf(" width=%d\n",cinfo.image_width); printf(" height=%d\n",cinfo.image_height); printf(" input_components=%d\n",cinfo.input_components); printf(" input_in_color_space=%d\n",cinfo.in_color_space); printf(" input_out_color_space=%d\n",cinfo.jpeg_color_space); printf(" num_components=%d\n",cinfo.num_components); } /* 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 */); /* Set the density so that the JFIF header has the correct settings */ cinfo.X_density=(UINT16)resolution; cinfo.Y_density=(UINT16)resolution; /* set the rows/columns setting to reflect the resolution */ cinfo.MCUs_per_row =16; cinfo.MCU_rows_in_scan=16; /* 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 , imageBuffer */ 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. */ //printf("image_height=%d, image_width=%d\n",cinfo.image_height, cinfo.image_width); row_pointer[0] = & imageBuffer[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(outfile); /* 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! */ } #endif /* * 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. * It's a bit more refined than the above, in that we show: * (a) how to modify the JPEG library's standard error-reporting behavior; * (b) how to allocate workspace using the library's memory manager. * * Just to make this example a little different from the first one, we'll * assume that we do not intend to put the whole image into an in-memory * buffer, but to send it line-by-line someplace else. We need a one- * scanline-high JSAMPLE array as a work buffer, and we will let the JPEG * memory manager allocate it for us. This approach is actually quite useful * because we don't need to remember to deallocate the buffer separately: it * will go away automatically when the JPEG object is cleaned up. */ /* * ERROR HANDLING: * * The JPEG library's standard error handler (jerror.c) is divided into * several "methods" which you can override individually. This lets you * adjust the behavior without duplicating a lot of code, which you might * have to update with each future release. * * Our example here shows how to override the "error_exit" method so that * control is returned to the library's caller when a fatal error occurs, * rather than calling exit() as the standard error_exit method does. * * We use C's setjmp/longjmp facility to return control. This means that the * routine which calls the JPEG library must first execute a setjmp() call to * establish the return point. We want the replacement error_exit to do a * longjmp(). But we need to make the setjmp buffer accessible to the * error_exit routine. To do this, we make a private extension of the * standard JPEG error handler object. (If we were using C++, we'd say we * were making a subclass of the regular error handler.) * * Here's the extended error handler struct: */ struct my_error_mgr { struct jpeg_error_mgr pub; /* "public" fields */ jmp_buf setjmp_buffer; /* for return to caller */ }; typedef struct my_error_mgr * my_error_ptr; /* * Here's the routine that will replace the standard error_exit method: */ METHODDEF(void) my_error_exit (j_common_ptr cinfo) { /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */ my_error_ptr myerr = (my_error_ptr) cinfo->err; /* Always display the message. */ /* We could postpone this until after returning, if we chose. */ (*cinfo->err->output_message) (cinfo); /* Return control to the setjmp point */ longjmp(myerr->setjmp_buffer, 1); } /* * Sample routine for JPEG decompression. We assume that the source file name * is passed in. We want to return 1 on success, 0 on error. */ #if 0 extern colorSpaceEnum sourceColorSpace; GLOBAL(int) read_JPEG_file (char * filename) { /* This struct contains the JPEG decompression parameters and pointers to * working space (which is allocated as needed by the JPEG library). */ struct jpeg_decompress_struct cinfo; /* We use our private extension JPEG error handler. * Note that this struct must live as long as the main JPEG parameter * struct, to avoid dangling-pointer problems. */ struct my_error_mgr jerr; /* More stuff */ FILE * infile; /* source file */ JSAMPARRAY buffer; /* Output row buffer */ int row_stride; /* physical row width in output buffer */ /* In this example we want to open the input file before doing anything else, * so that the setjmp() error recovery below can assume the file is open. * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that * requires it in order to read binary files. */ if ((infile = fopen(filename, "rb")) == NULL) { fprintf(stderr, "can't open %s\n", filename); return 0; } /* Step 1: allocate and initialize JPEG decompression object */ /* We set up the normal JPEG error routines, then override error_exit. */ cinfo.err = jpeg_std_error(&jerr.pub); jerr.pub.error_exit = my_error_exit; /* Establish the setjmp return context for my_error_exit to use. */ if (setjmp(jerr.setjmp_buffer)) { /* If we get here, the JPEG code has signaled an error. * We need to clean up the JPEG object, close the input file, and return. */ jpeg_destroy_decompress(&cinfo); fclose(infile); return 0; } /* Now we can initialize the JPEG decompression object. */ jpeg_create_decompress(&cinfo); /* Step 2: specify data source (eg, a file) */ jpeg_stdio_src(&cinfo, infile); /* Step 3: read file parameters with jpeg_read_header() */ (void) jpeg_read_header(&cinfo, TRUE); /* We can ignore the return value from jpeg_read_header since * (a) suspension is not possible with the stdio data source, and * (b) we passed TRUE to reject a tables-only JPEG file as an error. * See libjpeg.doc for more info. */ /* Step 4: set parameters for decompression */ /* In this example, we don't need to change any of the defaults set by * jpeg_read_header(), so we do nothing here. */ /* Step 5: Start decompressor */ (void) jpeg_start_decompress(&cinfo); if(DebugIt2) { printf("Source Image Stats\n"); printf(" Width=%d\n",cinfo.image_width); printf(" height=%d\n",cinfo.image_height); printf(" num_components=%d\n",cinfo.num_components); if(cinfo.out_color_space==JCS_RGB) { sourceColorSpace=RGB; printf(" JPEG color space==RGB\n"); } else if(cinfo.out_color_space==JCS_GRAYSCALE) { sourceColorSpace=GRAY; printf(" JPEG color space==RGB\n"); } else { sourceColorSpace=unknown; printf(" JPEG color space==RGB\n"); } } /* We can ignore the return value since suspension is not possible * with the stdio data source. */ /* We may need to do some setup of our own at this point before reading * the data. After jpeg_start_decompress() we have the correct scaled * output image dimensions available, as well as the output colormap * if we asked for color quantization. * In this example, we need to make an output work buffer of the right size. */ /* JSAMPLEs per row in output buffer */ row_stride = cinfo.output_width * cinfo.output_components; /* Make a one-row-high sample array that will go away when done with image */ buffer = (*cinfo.mem->alloc_sarray) ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1); /* Step 6: while (scan lines remain to be read) */ /* jpeg_read_scanlines(...); */ /* Here we use the library's state variable cinfo.output_scanline as the * loop counter, so that we don't have to keep track ourselves. */ while (cinfo.output_scanline < cinfo.output_height) { /* jpeg_read_scanlines expects an array of pointers to scanlines. * Here the array is only one element long, but you could ask for * more than one scanline at a time if that's more convenient. */ (void) jpeg_read_scanlines(&cinfo, buffer, 1); /* Assume put_scanline_someplace wants a pointer and sample count. */ put_scanline_someplace(&cinfo, (char *)buffer[0], row_stride); } /* Step 7: Finish decompression */ (void) jpeg_finish_decompress(&cinfo); /* We can ignore the return value since suspension is not possible * with the stdio data source. */ /* Step 8: Release JPEG decompression object */ /* This is an important step since it will release a good deal of memory. */ jpeg_destroy_decompress(&cinfo); /* After finish_decompress, we can close the input file. * Here we postpone it until after no more JPEG errors are possible, * so as to simplify the setjmp error logic above. (Actually, I don't * think that jpeg_destroy can do an error exit, but why assume anything...) */ fclose(infile); /* At this point you may want to check to see whether any corrupt-data * warnings occurred (test whether jerr.pub.num_warnings is nonzero). */ /* And we're done! */ return 1; } #endif