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/*
* jcmain.c
*
* Copyright (C) 1991, 1992, 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 trivial test user interface for the JPEG compressor.
* 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:
* cjpeg [options] inputfile outputfile
* cjpeg [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.
*/
#include "jinclude.h"
#ifdef INCLUDES_ARE_ANSI
#include <stdlib.h> /* to declare exit() */
#endif
#ifdef NEED_SIGNAL_CATCHER
#include <signal.h> /* to declare signal() */
#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 */
/*
* PD version of getopt(3).
*/
#include "egetopt.c"
/*
* This routine determines what format the input file is,
* and selects the appropriate input-reading module.
*
* To determine which family of input formats the file belongs to,
* we may look only at the first byte of the file, since C does not
* guarantee that more than one character can be pushed back with ungetc.
* Looking at additional bytes would require one of these approaches:
* 1) assume we can fseek() the input file (fails for piped input);
* 2) assume we can push back more than one character (works in
* some C implementations, but unportable);
* 3) provide our own buffering as is done in djpeg (breaks input readers
* that want to use stdio directly, such as the RLE library);
* or 4) don't put back the data, and modify the input_init methods to assume
* they start reading after the start of file (also breaks RLE library).
* #1 is attractive for MS-DOS but is untenable on Unix.
*
* The most portable solution for file types that can't be identified by their
* first byte is to make the user tell us what they are. This is also the
* only approach for "raw" file types that contain only arbitrary values.
* We presently apply this method for Targa files. Most of the time Targa
* files start with 0x00, so we recognize that case. Potentially, however,
* a Targa file could start with any byte value (byte 0 is the length of the
* seldom-used ID field), so we accept a -T switch to force Targa input mode.
*/
static boolean is_targa; /* records user -T switch */
LOCAL void
select_file_type (compress_info_ptr cinfo)
{
int c;
if (is_targa) {
#ifdef TARGA_SUPPORTED
jselrtarga(cinfo);
#else
ERREXIT(cinfo->emethods, "Targa support was not compiled");
#endif
return;
}
if ((c = getc(cinfo->input_file)) == EOF)
ERREXIT(cinfo->emethods, "Empty input file");
switch (c) {
#ifdef GIF_SUPPORTED
case 'G':
jselrgif(cinfo);
break;
#endif
#ifdef PPM_SUPPORTED
case 'P':
jselrppm(cinfo);
break;
#endif
#ifdef RLE_SUPPORTED
case 'R':
jselrrle(cinfo);
break;
#endif
#ifdef TARGA_SUPPORTED
case 0x00:
jselrtarga(cinfo);
break;
#endif
default:
#ifdef TARGA_SUPPORTED
ERREXIT(cinfo->emethods, "Unrecognized input file format --- did you forget -T ?");
#else
ERREXIT(cinfo->emethods, "Unrecognized input file format");
#endif
break;
}
if (ungetc(c, cinfo->input_file) == EOF)
ERREXIT(cinfo->emethods, "ungetc failed");
}
/*
* This routine gets control after the input file header has been read.
* It must determine what output JPEG file format is to be written,
* and make any other compression parameter changes that are desirable.
*/
METHODDEF void
c_ui_method_selection (compress_info_ptr cinfo)
{
/* If the input is gray scale, generate a monochrome JPEG file. */
if (cinfo->in_color_space == CS_GRAYSCALE)
j_monochrome_default(cinfo);
/* For now, always select JFIF output format. */
#ifdef JFIF_SUPPORTED
jselwjfif(cinfo);
#else
You shoulda defined JFIF_SUPPORTED. /* deliberate syntax error */
#endif
}
/*
* 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)
{
emethods->trace_level = 0; /* turn off trace output */
(*emethods->free_all) (); /* clean up memory allocation & temp files */
exit(EXIT_FAILURE);
}
#endif
LOCAL void
usage (char * progname)
/* complain about bad command line */
{
fprintf(stderr, "usage: %s ", progname);
fprintf(stderr, "[-Q quality 0..100] [-o] [-T] [-I] [-a] [-d] [-m mem]");
#ifdef TWO_FILE_COMMANDLINE
fprintf(stderr, " inputfile outputfile\n");
#else
fprintf(stderr, " [inputfile]\n");
#endif
exit(EXIT_FAILURE);
}
/*
* The main program.
*/
GLOBAL int
main (int argc, char **argv)
{
struct compress_info_struct cinfo;
struct compress_methods_struct c_methods;
struct external_methods_struct e_methods;
int c;
/* On Mac, fetch a command line. */
#ifdef THINK_C
argc = ccommand(&argv);
#endif
/* Initialize the system-dependent method pointers. */
cinfo.methods = &c_methods;
cinfo.emethods = &e_methods;
jselerror(&e_methods); /* error/trace message routines */
jselmemmgr(&e_methods); /* memory allocation routines */
c_methods.c_ui_method_selection = c_ui_method_selection;
/* Now OK to enable signal catcher. */
#ifdef NEED_SIGNAL_CATCHER
emethods = &e_methods;
signal(SIGINT, signal_catcher);
#ifdef SIGTERM /* not all systems have SIGTERM */
signal(SIGTERM, signal_catcher);
#endif
#endif
/* Set up default JPEG parameters. */
j_c_defaults(&cinfo, 75, FALSE); /* default quality level = 75 */
is_targa = FALSE;
/* Scan command line options, adjust parameters */
while ((c = egetopt(argc, argv, "IQ:Taom:d")) != EOF)
switch (c) {
case 'I': /* Create noninterleaved file. */
#ifdef MULTISCAN_FILES_SUPPORTED
cinfo.interleave = FALSE;
#else
fprintf(stderr, "%s: sorry, multiple-scan support was not compiled\n",
argv[0]);
exit(EXIT_FAILURE);
#endif
break;
case 'Q': /* Quality factor. */
{ int val;
if (optarg == NULL)
usage(argv[0]);
if (sscanf(optarg, "%d", &val) != 1)
usage(argv[0]);
/* Note: for now, we make force_baseline FALSE.
* This means non-baseline JPEG files can be created with low Q values.
* To ensure only baseline files are generated, pass TRUE instead.
*/
j_set_quality(&cinfo, val, FALSE);
}
break;
case 'T': /* Input file is Targa format. */
is_targa = TRUE;
break;
case 'a': /* Use arithmetic coding. */
#ifdef ARITH_CODING_SUPPORTED
cinfo.arith_code = TRUE;
#else
fprintf(stderr, "%s: sorry, arithmetic coding not supported\n",
argv[0]);
exit(EXIT_FAILURE);
#endif
break;
case 'o': /* Enable entropy parm optimization. */
#ifdef ENTROPY_OPT_SUPPORTED
cinfo.optimize_coding = TRUE;
#else
fprintf(stderr, "%s: sorry, entropy optimization was not compiled\n",
argv[0]);
exit(EXIT_FAILURE);
#endif
break;
case 'm': /* Maximum memory in Kb (or Mb with 'm'). */
{ long lval;
char ch = 'x';
if (optarg == NULL)
usage(argv[0]);
if (sscanf(optarg, "%ld%c", &lval, &ch) < 1)
usage(argv[0]);
if (ch == 'm' || ch == 'M')
lval *= 1000L;
e_methods.max_memory_to_use = lval * 1000L;
}
break;
case 'd': /* Debugging. */
e_methods.trace_level++;
break;
case '?':
default:
usage(argv[0]);
break;
}
/* If -d appeared, print version identification */
if (e_methods.trace_level > 0)
fprintf(stderr, "Independent JPEG Group's CJPEG, version %s\n%s\n",
JVERSION, JCOPYRIGHT);
/* Select the input and output files */
#ifdef TWO_FILE_COMMANDLINE
if (optind != argc-2) {
fprintf(stderr, "%s: must name one input and one output file\n", argv[0]);
usage(argv[0]);
}
if ((cinfo.input_file = fopen(argv[optind], READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s\n", argv[0], argv[optind]);
exit(EXIT_FAILURE);
}
if ((cinfo.output_file = fopen(argv[optind+1], WRITE_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s\n", argv[0], argv[optind+1]);
exit(EXIT_FAILURE);
}
#else /* not TWO_FILE_COMMANDLINE -- use Unix style */
cinfo.input_file = stdin; /* default input file */
cinfo.output_file = stdout; /* always the output file */
if (optind < argc-1) {
fprintf(stderr, "%s: only one input file\n", argv[0]);
usage(argv[0]);
}
if (optind < argc) {
if ((cinfo.input_file = fopen(argv[optind], READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s\n", argv[0], argv[optind]);
exit(EXIT_FAILURE);
}
}
#endif /* TWO_FILE_COMMANDLINE */
/* Figure out the input file format, and set up to read it. */
select_file_type(&cinfo);
/* Do it to it! */
jpeg_compress(&cinfo);
/* All done. */
exit(EXIT_SUCCESS);
return 0; /* suppress no-return-value warnings */
}
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