/*
* djpeg.c
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2013 by Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2010-2011, 2013-2017, D. R. Commander.
* Copyright (C) 2015, Google, Inc.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* This file contains a command-line user interface for the JPEG decompressor.
* It should work on any system with Unix- or MS-DOS-style command lines.
*
* Two different command line styles are permitted, depending on the
* compile-time switch TWO_FILE_COMMANDLINE:
* djpeg [options] inputfile outputfile
* djpeg [options] [inputfile]
* In the second style, output is always to standard output, which you'd
* normally redirect to a file or pipe to some other program. Input is
* either from a named file or from standard input (typically redirected).
* The second style is convenient on Unix but is unhelpful on systems that
* don't support pipes. Also, you MUST use the first style if your system
* doesn't do binary I/O to stdin/stdout.
* To simplify script writing, the "-outfile" switch is provided. The syntax
* djpeg [options] -outfile outputfile inputfile
* works regardless of which command line style is used.
*/
#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
#include "jversion.h" /* for version message */
#include "jconfigint.h"
#include <ctype.h> /* to declare isprint() */
#ifdef USE_CCOMMAND /* command-line reader for Macintosh */
#ifdef __MWERKS__
#include <SIOUX.h> /* Metrowerks needs this */
#include <console.h> /* ... and this */
#endif
#ifdef THINK_C
#include <console.h> /* Think declares it here */
#endif
#endif
/* Create the add-on message string table. */
#define JMESSAGE(code,string) string ,
static const char * const cdjpeg_message_table[] = {
#include "cderror.h"
NULL
};
/*
* This list defines the known output image formats
* (not all of which need be supported by a given version).
* You can change the default output format by defining DEFAULT_FMT;
* indeed, you had better do so if you undefine PPM_SUPPORTED.
*/
typedef enum {
FMT_BMP, /* BMP format (Windows flavor) */
FMT_GIF, /* GIF format */
FMT_OS2, /* BMP format (OS/2 flavor) */
FMT_PPM, /* PPM/PGM (PBMPLUS formats) */
FMT_RLE, /* RLE format */
FMT_TARGA, /* Targa format */
FMT_TIFF /* TIFF format */
} IMAGE_FORMATS;
#ifndef DEFAULT_FMT /* so can override from CFLAGS in Makefile */
#define DEFAULT_FMT FMT_PPM
#endif
static IMAGE_FORMATS requested_fmt;
/*
* Argument-parsing code.
* The switch parser is designed to be useful with DOS-style command line
* syntax, ie, intermixed switches and file names, where only the switches
* to the left of a given file name affect processing of that file.
* The main program in this file doesn't actually use this capability...
*/
static const char *progname; /* program name for error messages */
static char *outfilename; /* for -outfile switch */
boolean memsrc; /* for -memsrc switch */
boolean skip, crop;
JDIMENSION skip_start, skip_end;
JDIMENSION crop_x, crop_y, crop_width, crop_height;
#define INPUT_BUF_SIZE 4096
LOCAL(void)
usage (void)
/* complain about bad command line */
{
fprintf(stderr, "usage: %s [switches] ", progname);
#ifdef TWO_FILE_COMMANDLINE
fprintf(stderr, "inputfile outputfile\n");
#else
fprintf(stderr, "[inputfile]\n");
#endif
fprintf(stderr, "Switches (names may be abbreviated):\n");
fprintf(stderr, " -colors N Reduce image to no more than N colors\n");
fprintf(stderr, " -fast Fast, low-quality processing\n");
fprintf(stderr, " -grayscale Force grayscale output\n");
fprintf(stderr, " -rgb Force RGB output\n");
fprintf(stderr, " -rgb565 Force RGB565 output\n");
#ifdef IDCT_SCALING_SUPPORTED
fprintf(stderr, " -scale M/N Scale output image by fraction M/N, eg, 1/8\n");
#endif
#ifdef BMP_SUPPORTED
fprintf(stderr, " -bmp Select BMP output format (Windows style)%s\n",
(DEFAULT_FMT == FMT_BMP ? " (default)" : ""));
#endif
#ifdef GIF_SUPPORTED
fprintf(stderr, " -gif Select GIF output format%s\n",
(DEFAULT_FMT == FMT_GIF ? " (default)" : ""));
#endif
#ifdef BMP_SUPPORTED
fprintf(stderr, " -os2 Select BMP output format (OS/2 style)%s\n",
(DEFAULT_FMT == FMT_OS2 ? " (default)" : ""));
#endif
#ifdef PPM_SUPPORTED
fprintf(stderr, " -pnm Select PBMPLUS (PPM/PGM) output format%s\n",
(DEFAULT_FMT == FMT_PPM ? " (default)" : ""));
#endif
#ifdef RLE_SUPPORTED
fprintf(stderr, " -rle Select Utah RLE output format%s\n",
(DEFAULT_FMT == FMT_RLE ? " (default)" : ""));
#endif
#ifdef TARGA_SUPPORTED
fprintf(stderr, " -targa Select Targa output format%s\n",
(DEFAULT_FMT == FMT_TARGA ? " (default)" : ""));
#endif
fprintf(stderr, "Switches for advanced users:\n");
#ifdef DCT_ISLOW_SUPPORTED
fprintf(stderr, " -dct int Use integer DCT method%s\n",
(JDCT_DEFAULT == JDCT_ISLOW ? " (default)" : ""));
#endif
#ifdef DCT_IFAST_SUPPORTED
fprintf(stderr, " -dct fast Use fast integer DCT (less accurate)%s\n",
(JDCT_DEFAULT == JDCT_IFAST ? " (default)" : ""));
#endif
#ifdef DCT_FLOAT_SUPPORTED
fprintf(stderr, " -dct float Use floating-point DCT method%s\n",
(JDCT_DEFAULT == JDCT_FLOAT ? " (default)" : ""));
#endif
fprintf(stderr, " -dither fs Use F-S dithering (default)\n");
fprintf(stderr, " -dither none Don't use dithering in quantization\n");
fprintf(stderr, " -dither ordered Use ordered dither (medium speed, quality)\n");
#ifdef QUANT_2PASS_SUPPORTED
fprintf(stderr, " -map FILE Map to colors used in named image file\n");
#endif
fprintf(stderr, " -nosmooth Don't use high-quality upsampling\n");
#ifdef QUANT_1PASS_SUPPORTED
fprintf(stderr, " -onepass Use 1-pass quantization (fast, low quality)\n");
#endif
fprintf(stderr, " -maxmemory N Maximum memory to use (in kbytes)\n");
fprintf(stderr, " -outfile name Specify name for output file\n");
#if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
fprintf(stderr, " -memsrc Load input file into memory before decompressing\n");
#endif
fprintf(stderr, " -skip Y0,Y1 Decompress all rows except those between Y0 and Y1 (inclusive)\n");
fprintf(stderr, " -crop WxH+X+Y Decompress only a rectangular subregion of the image\n");
fprintf(stderr, " [requires PBMPLUS (PPM/PGM), GIF, or Targa output format]\n");
fprintf(stderr, " -verbose or -debug Emit debug output\n");
fprintf(stderr, " -version Print version information and exit\n");
exit(EXIT_FAILURE);
}
LOCAL(int)
parse_switches (j_decompress_ptr cinfo, int argc, char **argv,
int last_file_arg_seen, boolean for_real)
/* Parse optional switches.
* Returns argv[] index of first file-name argument (== argc if none).
* Any file names with indexes <= last_file_arg_seen are ignored;
* they have presumably been processed in a previous iteration.
* (Pass 0 for last_file_arg_seen on the first or only iteration.)
* for_real is FALSE on the first (dummy) pass; we may skip any expensive
* processing.
*/
{
int argn;
char *arg;
/* Set up default JPEG parameters. */
requested_fmt = DEFAULT_FMT; /* set default output file format */
outfilename = NULL;
memsrc = FALSE;
skip = FALSE;
crop = FALSE;
cinfo->err->trace_level = 0;
/* Scan command line options, adjust parameters */
for (argn = 1; argn < argc; argn++) {
arg = argv[argn];
if (*arg != '-') {
/* Not a switch, must be a file name argument */
if (argn <= last_file_arg_seen) {
outfilename = NULL; /* -outfile applies to just one input file */
continue; /* ignore this name if previously processed */
}
break; /* else done parsing switches */
}
arg++; /* advance past switch marker character */
if (keymatch(arg, "bmp", 1)) {
/* BMP output format. */
requested_fmt = FMT_BMP;
} else if (keymatch(arg, "colors", 1) || keymatch(arg, "colours", 1) ||
keymatch(arg, "quantize", 1) || keymatch(arg, "quantise", 1)) {
/* Do color quantization. */
int val;
if (++argn >= argc) /* advance to next argument */
usage();
if (sscanf(argv[argn], "%d", &val) != 1)
usage();
cinfo->desired_number_of_colors = val;
cinfo->quantize_colors = TRUE;
} else if (keymatch(arg, "dct", 2)) {
/* Select IDCT algorithm. */
if (++argn >= argc) /* advance to next argument */
usage();
if (keymatch(argv[argn], "int", 1)) {
cinfo->dct_method = JDCT_ISLOW;
} else if (keymatch(argv[argn], "fast", 2)) {
cinfo->dct_method = JDCT_IFAST;
} else if (keymatch(argv[argn], "float", 2)) {
cinfo->dct_method = JDCT_FLOAT;
} else
usage();
} else if (keymatch(arg, "dither", 2)) {
/* Select dithering algorithm. */
if (++argn >= argc) /* advance to next argument */
usage();
if (keymatch(argv[argn], "fs", 2)) {
cinfo->dither_mode = JDITHER_FS;
} else if (keymatch(argv[argn], "none", 2)) {
cinfo->dither_mode = JDITHER_NONE;
} else if (keymatch(argv[argn], "ordered", 2)) {
cinfo->dither_mode = JDITHER_ORDERED;
} else
usage();
} else if (keymatch(arg, "debug", 1) || keymatch(arg, "verbose", 1)) {
/* Enable debug printouts. */
/* On first -d, print version identification */
static boolean printed_version = FALSE;
if (! printed_version) {
fprintf(stderr, "%s version %s (build %s)\n",
PACKAGE_NAME, VERSION, BUILD);
fprintf(stderr, "%s\n\n", JCOPYRIGHT);
fprintf(stderr, "Emulating The Independent JPEG Group's software, version %s\n\n",
JVERSION);
printed_version = TRUE;
}
cinfo->err->trace_level++;
} else if (keymatch(arg, "version", 4)) {
fprintf(stderr, "%s version %s (build %s)\n",
PACKAGE_NAME, VERSION, BUILD);
exit(EXIT_SUCCESS);
} else if (keymatch(arg, "fast", 1)) {
/* Select recommended processing options for quick-and-dirty output. */
cinfo->two_pass_quantize = FALSE;
cinfo->dither_mode = JDITHER_ORDERED;
if (! cinfo->quantize_colors) /* don't override an earlier -colors */
cinfo->desired_number_of_colors = 216;
cinfo->dct_method = JDCT_FASTEST;
cinfo->do_fancy_upsampling = FALSE;
} else if (keymatch(arg, "gif", 1)) {
/* GIF output format. */
requested_fmt = FMT_GIF;
} else if (keymatch(arg, "grayscale", 2) || keymatch(arg, "greyscale",2)) {
/* Force monochrome output. */
cinfo->out_color_space = JCS_GRAYSCALE;
} else if (keymatch(arg, "rgb", 2)) {
/* Force RGB output. */
cinfo->out_color_space = JCS_RGB;
} else if (keymatch(arg, "rgb565", 2)) {
/* Force RGB565 output. */
cinfo->out_color_space = JCS_RGB565;
} else if (keymatch(arg, "map", 3)) {
/* Quantize to a color map taken from an input file. */
if (++argn >= argc) /* advance to next argument */
usage();
if (for_real) { /* too expensive to do twice! */
#ifdef QUANT_2PASS_SUPPORTED /* otherwise can't quantize to supplied map */
FILE *mapfile;
if ((mapfile = fopen(argv[argn], READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]);
exit(EXIT_FAILURE);
}
read_color_map(cinfo, mapfile);
fclose(mapfile);
cinfo->quantize_colors = TRUE;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
}
} else if (keymatch(arg, "maxmemory", 3)) {
/* Maximum memory in Kb (or Mb with 'm'). */
long lval;
char ch = 'x';
if (++argn >= argc) /* advance to next argument */
usage();
if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)
usage();
if (ch == 'm' || ch == 'M')
lval *= 1000L;
cinfo->mem->max_memory_to_use = lval * 1000L;
} else if (keymatch(arg, "nosmooth", 3)) {
/* Suppress fancy upsampling */
cinfo->do_fancy_upsampling = FALSE;
} else if (keymatch(arg, "onepass", 3)) {
/* Use fast one-pass quantization. */
cinfo->two_pass_quantize = FALSE;
} else if (keymatch(arg, "os2", 3)) {
/* BMP output format (OS/2 flavor). */
requested_fmt = FMT_OS2;
} else if (keymatch(arg, "outfile", 4)) {
/* Set output file name. */
if (++argn >= argc) /* advance to next argument */
usage();
outfilename = argv[argn]; /* save it away for later use */
} else if (keymatch(arg, "memsrc", 2)) {
/* Use in-memory source manager */
#if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
memsrc = TRUE;
#else
fprintf(stderr, "%s: sorry, in-memory source manager was not compiled in\n",
progname);
exit(EXIT_FAILURE);
#endif
} else if (keymatch(arg, "pnm", 1) || keymatch(arg, "ppm", 1)) {
/* PPM/PGM output format. */
requested_fmt = FMT_PPM;
} else if (keymatch(arg, "rle", 1)) {
/* RLE output format. */
requested_fmt = FMT_RLE;
} else if (keymatch(arg, "scale", 2)) {
/* Scale the output image by a fraction M/N. */
if (++argn >= argc) /* advance to next argument */
usage();
if (sscanf(argv[argn], "%u/%u",
&cinfo->scale_num, &cinfo->scale_denom) != 2)
usage();
} else if (keymatch(arg, "skip", 2)) {
if (++argn >= argc)
usage();
if (sscanf(argv[argn], "%u,%u", &skip_start, &skip_end) != 2 ||
skip_start > skip_end)
usage();
skip = TRUE;
} else if (keymatch(arg, "crop", 2)) {
char c;
if (++argn >= argc)
usage();
if (sscanf(argv[argn], "%u%c%u+%u+%u", &crop_width, &c, &crop_height,
&crop_x, &crop_y) != 5 ||
(c != 'X' && c != 'x') || crop_width < 1 || crop_height < 1)
usage();
crop = TRUE;
} else if (keymatch(arg, "targa", 1)) {
/* Targa output format. */
requested_fmt = FMT_TARGA;
} else {
usage(); /* bogus switch */
}
}
return argn; /* return index of next arg (file name) */
}
/*
* Marker processor for COM and interesting APPn markers.
* This replaces the library's built-in processor, which just skips the marker.
* We want to print out the marker as text, to the extent possible.
* Note this code relies on a non-suspending data source.
*/
LOCAL(unsigned int)
jpeg_getc (j_decompress_ptr cinfo)
/* Read next byte */
{
struct jpeg_source_mgr *datasrc = cinfo->src;
if (datasrc->bytes_in_buffer == 0) {
if (! (*datasrc->fill_input_buffer) (cinfo))
ERREXIT(cinfo, JERR_CANT_SUSPEND);
}
datasrc->bytes_in_buffer--;
return GETJOCTET(*datasrc->next_input_byte++);
}
METHODDEF(boolean)
print_text_marker (j_decompress_ptr cinfo)
{
boolean traceit = (cinfo->err->trace_level >= 1);
long length;
unsigned int ch;
unsigned int lastch = 0;
length = jpeg_getc(cinfo) << 8;
length += jpeg_getc(cinfo);
length -= 2; /* discount the length word itself */
if (traceit) {
if (cinfo->unread_marker == JPEG_COM)
fprintf(stderr, "Comment, length %ld:\n", (long) length);
else /* assume it is an APPn otherwise */
fprintf(stderr, "APP%d, length %ld:\n",
cinfo->unread_marker - JPEG_APP0, (long) length);
}
while (--length >= 0) {
ch = jpeg_getc(cinfo);
if (traceit) {
/* Emit the character in a readable form.
* Nonprintables are converted to \nnn form,
* while \ is converted to \\.
* Newlines in CR, CR/LF, or LF form will be printed as one newline.
*/
if (ch == '\r') {
fprintf(stderr, "\n");
} else if (ch == '\n') {
if (lastch != '\r')
fprintf(stderr, "\n");
} else if (ch == '\\') {
fprintf(stderr, "\\\\");
} else if (isprint(ch)) {
putc(ch, stderr);
} else {
fprintf(stderr, "\\%03o", ch);
}
lastch = ch;
}
}
if (traceit)
fprintf(stderr, "\n");
return TRUE;
}
/*
* The main program.
*/
int
main (int argc, char **argv)
{
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
#ifdef PROGRESS_REPORT
struct cdjpeg_progress_mgr progress;
#endif
int file_index;
djpeg_dest_ptr dest_mgr = NULL;
FILE *input_file;
FILE *output_file;
unsigned char *inbuffer = NULL;
unsigned long insize = 0;
JDIMENSION num_scanlines;
/* On Mac, fetch a command line. */
#ifdef USE_CCOMMAND
argc = ccommand(&argv);
#endif
progname = argv[0];
if (progname == NULL || progname[0] == 0)
progname = "djpeg"; /* in case C library doesn't provide it */
/* Initialize the JPEG decompression object with default error handling. */
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_decompress(&cinfo);
/* Add some application-specific error messages (from cderror.h) */
jerr.addon_message_table = cdjpeg_message_table;
jerr.first_addon_message = JMSG_FIRSTADDONCODE;
jerr.last_addon_message = JMSG_LASTADDONCODE;
/* Insert custom marker processor for COM and APP12.
* APP12 is used by some digital camera makers for textual info,
* so we provide the ability to display it as text.
* If you like, additional APPn marker types can be selected for display,
* but don't try to override APP0 or APP14 this way (see libjpeg.txt).
*/
jpeg_set_marker_processor(&cinfo, JPEG_COM, print_text_marker);
jpeg_set_marker_processor(&cinfo, JPEG_APP0+12, print_text_marker);
/* Scan command line to find file names. */
/* It is convenient to use just one switch-parsing routine, but the switch
* values read here are ignored; we will rescan the switches after opening
* the input file.
* (Exception: tracing level set here controls verbosity for COM markers
* found during jpeg_read_header...)
*/
file_index = parse_switches(&cinfo, argc, argv, 0, FALSE);
#ifdef TWO_FILE_COMMANDLINE
/* Must have either -outfile switch or explicit output file name */
if (outfilename == NULL) {
if (file_index != argc-2) {
fprintf(stderr, "%s: must name one input and one output file\n",
progname);
usage();
}
outfilename = argv[file_index+1];
} else {
if (file_index != argc-1) {
fprintf(stderr, "%s: must name one input and one output file\n",
progname);
usage();
}
}
#else
/* Unix style: expect zero or one file name */
if (file_index < argc-1) {
fprintf(stderr, "%s: only one input file\n", progname);
usage();
}
#endif /* TWO_FILE_COMMANDLINE */
/* Open the input file. */
if (file_index < argc) {
if ((input_file = fopen(argv[file_index], READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s\n", progname, argv[file_index]);
exit(EXIT_FAILURE);
}
} else {
/* default input file is stdin */
input_file = read_stdin();
}
/* Open the output file. */
if (outfilename != NULL) {
if ((output_file = fopen(outfilename, WRITE_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s\n", progname, outfilename);
exit(EXIT_FAILURE);
}
} else {
/* default output file is stdout */
output_file = write_stdout();
}
#ifdef PROGRESS_REPORT
start_progress_monitor((j_common_ptr) &cinfo, &progress);
#endif
/* Specify data source for decompression */
#if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
if (memsrc) {
size_t nbytes;
do {
inbuffer = (unsigned char *)realloc(inbuffer, insize + INPUT_BUF_SIZE);
if (inbuffer == NULL) {
fprintf(stderr, "%s: memory allocation failure\n", progname);
exit(EXIT_FAILURE);
}
nbytes = JFREAD(input_file, &inbuffer[insize], INPUT_BUF_SIZE);
if (nbytes < INPUT_BUF_SIZE && ferror(input_file)) {
if (file_index < argc)
fprintf(stderr, "%s: can't read from %s\n", progname,
argv[file_index]);
else
fprintf(stderr, "%s: can't read from stdin\n", progname);
}
insize += (unsigned long)nbytes;
} while (nbytes == INPUT_BUF_SIZE);
fprintf(stderr, "Compressed size: %lu bytes\n", insize);
jpeg_mem_src(&cinfo, inbuffer, insize);
} else
#endif
jpeg_stdio_src(&cinfo, input_file);
/* Read file header, set default decompression parameters */
(void) jpeg_read_header(&cinfo, TRUE);
/* Adjust default decompression parameters by re-parsing the options */
file_index = parse_switches(&cinfo, argc, argv, 0, TRUE);
/* Initialize the output module now to let it override any crucial
* option settings (for instance, GIF wants to force color quantization).
*/
switch (requested_fmt) {
#ifdef BMP_SUPPORTED
case FMT_BMP:
dest_mgr = jinit_write_bmp(&cinfo, FALSE);
break;
case FMT_OS2:
dest_mgr = jinit_write_bmp(&cinfo, TRUE);
break;
#endif
#ifdef GIF_SUPPORTED
case FMT_GIF:
dest_mgr = jinit_write_gif(&cinfo);
break;
#endif
#ifdef PPM_SUPPORTED
case FMT_PPM:
dest_mgr = jinit_write_ppm(&cinfo);
break;
#endif
#ifdef RLE_SUPPORTED
case FMT_RLE:
dest_mgr = jinit_write_rle(&cinfo);
break;
#endif
#ifdef TARGA_SUPPORTED
case FMT_TARGA:
dest_mgr = jinit_write_targa(&cinfo);
break;
#endif
default:
ERREXIT(&cinfo, JERR_UNSUPPORTED_FORMAT);
break;
}
dest_mgr->output_file = output_file;
/* Start decompressor */
(void) jpeg_start_decompress(&cinfo);
/* Skip rows */
if (skip) {
JDIMENSION tmp;
/* Check for valid skip_end. We cannot check this value until after
* jpeg_start_decompress() is called. Note that we have already verified
* that skip_start <= skip_end.
*/
if (skip_end > cinfo.output_height - 1) {
fprintf(stderr, "%s: skip region exceeds image height %d\n", progname,
cinfo.output_height);
exit(EXIT_FAILURE);
}
/* Write output file header. This is a hack to ensure that the destination
* manager creates an output image of the proper size.
*/
tmp = cinfo.output_height;
cinfo.output_height -= (skip_end - skip_start + 1);
(*dest_mgr->start_output) (&cinfo, dest_mgr);
cinfo.output_height = tmp;
/* Process data */
while (cinfo.output_scanline < skip_start) {
num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
dest_mgr->buffer_height);
(*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
}
jpeg_skip_scanlines(&cinfo, skip_end - skip_start + 1);
while (cinfo.output_scanline < cinfo.output_height) {
num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
dest_mgr->buffer_height);
(*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
}
/* Decompress a subregion */
} else if (crop) {
JDIMENSION tmp;
/* Check for valid crop dimensions. We cannot check these values until
* after jpeg_start_decompress() is called.
*/
if (crop_x + crop_width > cinfo.output_width ||
crop_y + crop_height > cinfo.output_height) {
fprintf(stderr, "%s: crop dimensions exceed image dimensions %d x %d\n",
progname, cinfo.output_width, cinfo.output_height);
exit(EXIT_FAILURE);
}
jpeg_crop_scanline(&cinfo, &crop_x, &crop_width);
if (dest_mgr->calc_buffer_dimensions)
(*dest_mgr->calc_buffer_dimensions) (&cinfo, dest_mgr);
else
ERREXIT(&cinfo, JERR_UNSUPPORTED_FORMAT);
/* Write output file header. This is a hack to ensure that the destination
* manager creates an output image of the proper size.
*/
tmp = cinfo.output_height;
cinfo.output_height = crop_height;
(*dest_mgr->start_output) (&cinfo, dest_mgr);
cinfo.output_height = tmp;
/* Process data */
jpeg_skip_scanlines(&cinfo, crop_y);
while (cinfo.output_scanline < crop_y + crop_height) {
num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
dest_mgr->buffer_height);
(*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
}
jpeg_skip_scanlines(&cinfo, cinfo.output_height - crop_y - crop_height);
/* Normal full-image decompress */
} else {
/* Write output file header */
(*dest_mgr->start_output) (&cinfo, dest_mgr);
/* Process data */
while (cinfo.output_scanline < cinfo.output_height) {
num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
dest_mgr->buffer_height);
(*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
}
}
#ifdef PROGRESS_REPORT
/* Hack: count final pass as done in case finish_output does an extra pass.
* The library won't have updated completed_passes.
*/
progress.pub.completed_passes = progress.pub.total_passes;
#endif
/* Finish decompression and release memory.
* I must do it in this order because output module has allocated memory
* of lifespan JPOOL_IMAGE; it needs to finish before releasing memory.
*/
(*dest_mgr->finish_output) (&cinfo, dest_mgr);
(void) jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
/* Close files, if we opened them */
if (input_file != stdin)
fclose(input_file);
if (output_file != stdout)
fclose(output_file);
#ifdef PROGRESS_REPORT
end_progress_monitor((j_common_ptr) &cinfo);
#endif
if (memsrc && inbuffer != NULL)
free(inbuffer);
/* All done. */
exit(jerr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS);
return 0; /* suppress no-return-value warnings */
}