libjpeg-turbo/jdmain.c
2015-07-29 15:25:01 -05:00

515 lines
15 KiB
C

/*
* jdmain.c
*
* Copyright (C) 1991, 1992, 1993, 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 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 "jinclude.h"
#ifdef INCLUDES_ARE_ANSI
#include <stdlib.h> /* to declare exit() */
#endif
#include <ctype.h> /* to declare isupper(), tolower() */
#ifdef NEED_SIGNAL_CATCHER
#include <signal.h> /* to declare signal() */
#endif
#ifdef USE_SETMODE
#include <fcntl.h> /* to declare setmode() */
#endif
#ifdef THINK_C
#include <console.h> /* command-line reader for Macintosh */
#endif
#ifdef DONT_USE_B_MODE /* define mode parameters for fopen() */
#define READ_BINARY "r"
#define WRITE_BINARY "w"
#else
#define READ_BINARY "rb"
#define WRITE_BINARY "wb"
#endif
#ifndef EXIT_FAILURE /* define exit() codes if not provided */
#define EXIT_FAILURE 1
#endif
#ifndef EXIT_SUCCESS
#ifdef VMS
#define EXIT_SUCCESS 1 /* VMS is very nonstandard */
#else
#define EXIT_SUCCESS 0
#endif
#endif
#include "jversion.h" /* for version message */
/*
* 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_GIF, /* GIF format */
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;
/*
* This routine gets control after the input file header has been read.
* It must determine what output file format is to be written,
* and make any other decompression parameter changes that are desirable.
*/
METHODDEF void
d_ui_method_selection (decompress_info_ptr cinfo)
{
/* if grayscale or CMYK input, force similar output; */
/* else leave the output colorspace as set by options. */
if (cinfo->jpeg_color_space == CS_GRAYSCALE)
cinfo->out_color_space = CS_GRAYSCALE;
else if (cinfo->jpeg_color_space == CS_CMYK)
cinfo->out_color_space = CS_CMYK;
/* select output file format */
/* Note: jselwxxx routine may make additional parameter changes,
* such as forcing color quantization if it's a colormapped format.
*/
switch (requested_fmt) {
#ifdef GIF_SUPPORTED
case FMT_GIF:
jselwgif(cinfo);
break;
#endif
#ifdef PPM_SUPPORTED
case FMT_PPM:
jselwppm(cinfo);
break;
#endif
#ifdef RLE_SUPPORTED
case FMT_RLE:
jselwrle(cinfo);
break;
#endif
#ifdef TARGA_SUPPORTED
case FMT_TARGA:
jselwtarga(cinfo);
break;
#endif
default:
ERREXIT(cinfo->emethods, "Unsupported output file format");
break;
}
}
/*
* Signal catcher to ensure that temporary files are removed before aborting.
* NB: for Amiga Manx C this is actually a global routine named _abort();
* see -Dsignal_catcher=_abort in CFLAGS. Talk about bogus...
*/
#ifdef NEED_SIGNAL_CATCHER
static external_methods_ptr emethods; /* for access to free_all */
GLOBAL void
signal_catcher (int signum)
{
if (emethods != NULL) {
emethods->trace_level = 0; /* turn off trace output */
(*emethods->free_all) (); /* clean up memory allocation & temp files */
}
exit(EXIT_FAILURE);
}
#endif
/*
* Optional routine to display a percent-done figure on stderr.
* See jddeflts.c for explanation of the information used.
*/
#ifdef PROGRESS_REPORT
METHODDEF void
progress_monitor (decompress_info_ptr cinfo, long loopcounter, long looplimit)
{
if (cinfo->total_passes > 1) {
fprintf(stderr, "\rPass %d/%d: %3d%% ",
cinfo->completed_passes+1, cinfo->total_passes,
(int) (loopcounter*100L/looplimit));
} else {
fprintf(stderr, "\r %3d%% ",
(int) (loopcounter*100L/looplimit));
}
fflush(stderr);
}
#endif
/*
* 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 char * progname; /* program name for error messages */
static char * outfilename; /* for -outfile switch */
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");
#ifdef GIF_SUPPORTED
fprintf(stderr, " -gif Select GIF output format\n");
#endif
#ifdef PPM_SUPPORTED
fprintf(stderr, " -pnm Select PBMPLUS (PPM/PGM) output format (default)\n");
#endif
fprintf(stderr, " -quantize N Same as -colors N\n");
#ifdef RLE_SUPPORTED
fprintf(stderr, " -rle Select Utah RLE output format\n");
#endif
#ifdef TARGA_SUPPORTED
fprintf(stderr, " -targa Select Targa output format\n");
#endif
fprintf(stderr, "Switches for advanced users:\n");
#ifdef BLOCK_SMOOTHING_SUPPORTED
fprintf(stderr, " -blocksmooth Apply cross-block smoothing\n");
#endif
fprintf(stderr, " -grayscale Force grayscale output\n");
fprintf(stderr, " -nodither Don't use dithering in quantization\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, " -verbose or -debug Emit debug output\n");
exit(EXIT_FAILURE);
}
LOCAL boolean
keymatch (char * arg, const char * keyword, int minchars)
/* Case-insensitive matching of (possibly abbreviated) keyword switches. */
/* keyword is the constant keyword (must be lower case already), */
/* minchars is length of minimum legal abbreviation. */
{
register int ca, ck;
register int nmatched = 0;
while ((ca = *arg++) != '\0') {
if ((ck = *keyword++) == '\0')
return FALSE; /* arg longer than keyword, no good */
if (isupper(ca)) /* force arg to lcase (assume ck is already) */
ca = tolower(ca);
if (ca != ck)
return FALSE; /* no good */
nmatched++; /* count matched characters */
}
/* reached end of argument; fail if it's too short for unique abbrev */
if (nmatched < minchars)
return FALSE;
return TRUE; /* A-OK */
}
LOCAL int
parse_switches (decompress_info_ptr cinfo, int last_file_arg_seen,
int argc, char **argv)
/* Initialize cinfo with default switch settings, then parse option 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.)
*/
{
int argn;
char * arg;
/* (Re-)initialize the system-dependent error and memory managers. */
jselerror(cinfo->emethods); /* error/trace message routines */
jselmemmgr(cinfo->emethods); /* memory allocation routines */
cinfo->methods->d_ui_method_selection = d_ui_method_selection;
/* Now OK to enable signal catcher. */
#ifdef NEED_SIGNAL_CATCHER
emethods = cinfo->emethods;
#endif
/* Set up default JPEG parameters. */
j_d_defaults(cinfo, TRUE);
requested_fmt = DEFAULT_FMT; /* set default output file format */
outfilename = NULL;
/* 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, "blocksmooth", 1)) {
/* Enable cross-block smoothing. */
cinfo->do_block_smoothing = TRUE;
} 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, "debug", 1) || keymatch(arg, "verbose", 1)) {
/* Enable debug printouts. */
/* On first -d, print version identification */
if (last_file_arg_seen == 0 && cinfo->emethods->trace_level == 0)
fprintf(stderr, "Independent JPEG Group's DJPEG, version %s\n%s\n",
JVERSION, JCOPYRIGHT);
cinfo->emethods->trace_level++;
} 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 = CS_GRAYSCALE;
} else if (keymatch(arg, "maxmemory", 1)) {
/* 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->emethods->max_memory_to_use = lval * 1000L;
} else if (keymatch(arg, "nodither", 3)) {
/* Suppress dithering in color quantization. */
cinfo->use_dithering = FALSE;
} else if (keymatch(arg, "onepass", 1)) {
/* Use fast one-pass quantization. */
cinfo->two_pass_quantize = FALSE;
} else if (keymatch(arg, "outfile", 3)) {
/* 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, "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, "targa", 1)) {
/* Targa output format. */
requested_fmt = FMT_TARGA;
} else {
usage(); /* bogus switch */
}
}
return argn; /* return index of next arg (file name) */
}
/*
* The main program.
*/
GLOBAL int
main (int argc, char **argv)
{
struct Decompress_info_struct cinfo;
struct Decompress_methods_struct dc_methods;
struct External_methods_struct e_methods;
int file_index;
/* On Mac, fetch a command line. */
#ifdef THINK_C
argc = ccommand(&argv);
#endif
progname = argv[0];
/* Set up links to method structures. */
cinfo.methods = &dc_methods;
cinfo.emethods = &e_methods;
/* Install, but don't yet enable signal catcher. */
#ifdef NEED_SIGNAL_CATCHER
emethods = NULL;
signal(SIGINT, signal_catcher);
#ifdef SIGTERM /* not all systems have SIGTERM */
signal(SIGTERM, signal_catcher);
#endif
#endif
/* Scan command line: set up compression parameters, find file names. */
file_index = parse_switches(&cinfo, 0, argc, argv);
#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 ((cinfo.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 */
#ifdef USE_SETMODE /* need to hack file mode? */
setmode(fileno(stdin), O_BINARY);
#endif
#ifdef USE_FDOPEN /* need to re-open in binary mode? */
if ((cinfo.input_file = fdopen(fileno(stdin), READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open stdin\n", progname);
exit(EXIT_FAILURE);
}
#else
cinfo.input_file = stdin;
#endif
}
/* Open the output file. */
if (outfilename != NULL) {
if ((cinfo.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 */
#ifdef USE_SETMODE /* need to hack file mode? */
setmode(fileno(stdout), O_BINARY);
#endif
#ifdef USE_FDOPEN /* need to re-open in binary mode? */
if ((cinfo.output_file = fdopen(fileno(stdout), WRITE_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open stdout\n", progname);
exit(EXIT_FAILURE);
}
#else
cinfo.output_file = stdout;
#endif
}
/* Set up to read a JFIF or baseline-JPEG file. */
/* A smarter UI would inspect the first few bytes of the input file */
/* to determine its type. */
#ifdef JFIF_SUPPORTED
jselrjfif(&cinfo);
#else
You shoulda defined JFIF_SUPPORTED. /* deliberate syntax error */
#endif
#ifdef PROGRESS_REPORT
/* Start up progress display, unless trace output is on */
if (e_methods.trace_level == 0)
dc_methods.progress_monitor = progress_monitor;
#endif
/* Do it to it! */
jpeg_decompress(&cinfo);
#ifdef PROGRESS_REPORT
/* Clear away progress display */
if (e_methods.trace_level == 0) {
fprintf(stderr, "\r \r");
fflush(stderr);
}
#endif
/* All done. */
exit(EXIT_SUCCESS);
return 0; /* suppress no-return-value warnings */
}