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/*
* cjpeg.c
*
* Copyright (C) 1991-1998, 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 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.
* To simplify script writing, the "-outfile" switch is provided. The syntax
* cjpeg [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 */
#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 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 (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 provide a switch to force Targa input mode.
*/
static boolean is_targa
; /* records user -targa switch */
LOCAL
(cjpeg_source_ptr
)
select_file_type
(j_compress_ptr cinfo
, FILE
* infile
)
{
int c
;
if (is_targa
) {
#ifdef TARGA_SUPPORTED
return jinit_read_targa
(cinfo
);
#else
ERREXIT
(cinfo
, JERR_TGA_NOTCOMP
);
#endif
}
if ((c
= getc(infile
)) == EOF
)
ERREXIT
(cinfo
, JERR_INPUT_EMPTY
);
if (ungetc(c
, infile
) == EOF
)
ERREXIT
(cinfo
, JERR_UNGETC_FAILED
);
switch (c
) {
#ifdef BMP_SUPPORTED
case 'B':
return jinit_read_bmp
(cinfo
);
#endif
#ifdef GIF_SUPPORTED
case 'G':
return jinit_read_gif
(cinfo
);
#endif
#ifdef PPM_SUPPORTED
case 'P':
return jinit_read_ppm
(cinfo
);
#endif
#ifdef RLE_SUPPORTED
case 'R':
return jinit_read_rle
(cinfo
);
#endif
#ifdef TARGA_SUPPORTED
case 0x00:
return jinit_read_targa
(cinfo
);
#endif
default:
ERREXIT
(cinfo
, JERR_UNKNOWN_FORMAT
);
break;
}
return NULL
; /* suppress compiler warnings */
}
/*
* 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 */
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
, " -quality N Compression quality (0..100; 5-95 is useful range)\n");
fprintf(stderr
, " -grayscale Create monochrome JPEG file\n");
#ifdef ENTROPY_OPT_SUPPORTED
fprintf(stderr
, " -optimize Optimize Huffman table (smaller file, but slow compression)\n");
#endif
#ifdef C_PROGRESSIVE_SUPPORTED
fprintf(stderr
, " -progressive Create progressive JPEG file\n");
#endif
#ifdef TARGA_SUPPORTED
fprintf(stderr
, " -targa Input file is Targa format (usually not needed)\n");
#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
, " -restart N Set restart interval in rows, or in blocks with B\n");
#ifdef INPUT_SMOOTHING_SUPPORTED
fprintf(stderr
, " -smooth N Smooth dithered input (N=1..100 is strength)\n");
#endif
fprintf(stderr
, " -maxmemory N Maximum memory to use (in kbytes)\n");
fprintf(stderr
, " -outfile name Specify name for output file\n");
fprintf(stderr
, " -verbose or -debug Emit debug output\n");
fprintf(stderr
, "Switches for wizards:\n");
#ifdef C_ARITH_CODING_SUPPORTED
fprintf(stderr
, " -arithmetic Use arithmetic coding\n");
#endif
fprintf(stderr
, " -baseline Force baseline quantization tables\n");
fprintf(stderr
, " -qtables file Use quantization tables given in file\n");
fprintf(stderr
, " -qslots N[,...] Set component quantization tables\n");
fprintf(stderr
, " -sample HxV[,...] Set component sampling factors\n");
#ifdef C_MULTISCAN_FILES_SUPPORTED
fprintf(stderr
, " -scans file Create multi-scan JPEG per script file\n");
#endif
exit(EXIT_FAILURE
);
}
LOCAL
(int)
parse_switches
(j_compress_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
;
int quality
; /* -quality parameter */
int q_scale_factor
; /* scaling percentage for -qtables */
boolean force_baseline
;
boolean simple_progressive
;
char * qtablefile
= NULL
; /* saves -qtables filename if any */
char * qslotsarg
= NULL
; /* saves -qslots parm if any */
char * samplearg
= NULL
; /* saves -sample parm if any */
char * scansarg
= NULL
; /* saves -scans parm if any */
/* Set up default JPEG parameters. */
/* Note that default -quality level need not, and does not,
* match the default scaling for an explicit -qtables argument.
*/
quality
= 75; /* default -quality value */
q_scale_factor
= 100; /* default to no scaling for -qtables */
force_baseline
= FALSE
; /* by default, allow 16-bit quantizers */
simple_progressive
= FALSE
;
is_targa
= FALSE
;
outfilename
= NULL
;
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
, "arithmetic", 1)) {
/* Use arithmetic coding. */
#ifdef C_ARITH_CODING_SUPPORTED
cinfo
->arith_code
= TRUE
;
#else
fprintf(stderr
, "%s: sorry, arithmetic coding not supported\n",
progname
);
exit(EXIT_FAILURE
);
#endif
} else if (keymatch
(arg
, "baseline", 1)) {
/* Force baseline-compatible output (8-bit quantizer values). */
force_baseline
= TRUE
;
} else if (keymatch
(arg
, "dct", 2)) {
/* Select DCT 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
, "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
, "Independent JPEG Group's CJPEG, version %s\n%s\n",
JVERSION
, JCOPYRIGHT
);
printed_version
= TRUE
;
}
cinfo
->err
->trace_level
++;
} else if (keymatch
(arg
, "grayscale", 2) || keymatch
(arg
, "greyscale",2)) {
/* Force a monochrome JPEG file to be generated. */
jpeg_set_colorspace
(cinfo
, JCS_GRAYSCALE
);
} 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
, "optimize", 1) || keymatch
(arg
, "optimise", 1)) {
/* Enable entropy parm optimization. */
#ifdef ENTROPY_OPT_SUPPORTED
cinfo
->optimize_coding
= TRUE
;
#else
fprintf(stderr
, "%s: sorry, entropy optimization was not compiled\n",
progname
);
exit(EXIT_FAILURE
);
#endif
} 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
, "progressive", 1)) {
/* Select simple progressive mode. */
#ifdef C_PROGRESSIVE_SUPPORTED
simple_progressive
= TRUE
;
/* We must postpone execution until num_components is known. */
#else
fprintf(stderr
, "%s: sorry, progressive output was not compiled\n",
progname
);
exit(EXIT_FAILURE
);
#endif
} else if (keymatch
(arg
, "quality", 1)) {
/* Quality factor (quantization table scaling factor). */
if (++argn
>= argc
) /* advance to next argument */
usage
();
if (sscanf(argv
[argn
], "%d", &quality
) != 1)
usage
();
/* Change scale factor in case -qtables is present. */
q_scale_factor
= jpeg_quality_scaling
(quality
);
} else if (keymatch
(arg
, "qslots", 2)) {
/* Quantization table slot numbers. */
if (++argn
>= argc
) /* advance to next argument */
usage
();
qslotsarg
= argv
[argn
];
/* Must delay setting qslots until after we have processed any
* colorspace-determining switches, since jpeg_set_colorspace sets
* default quant table numbers.
*/
} else if (keymatch
(arg
, "qtables", 2)) {
/* Quantization tables fetched from file. */
if (++argn
>= argc
) /* advance to next argument */
usage
();
qtablefile
= argv
[argn
];
/* We postpone actually reading the file in case -quality comes later. */
} else if (keymatch
(arg
, "restart", 1)) {
/* Restart interval in MCU rows (or in MCUs with 'b'). */
long lval
;
char ch
= 'x';
if (++argn
>= argc
) /* advance to next argument */
usage
();
if (sscanf(argv
[argn
], "%ld%c", &lval
, &ch
) < 1)
usage
();
if (lval
< 0 || lval
> 65535L)
usage
();
if (ch
== 'b' || ch
== 'B') {
cinfo
->restart_interval
= (unsigned int) lval
;
cinfo
->restart_in_rows
= 0; /* else prior '-restart n' overrides me */
} else {
cinfo
->restart_in_rows
= (int) lval
;
/* restart_interval will be computed during startup */
}
} else if (keymatch
(arg
, "sample", 2)) {
/* Set sampling factors. */
if (++argn
>= argc
) /* advance to next argument */
usage
();
samplearg
= argv
[argn
];
/* Must delay setting sample factors until after we have processed any
* colorspace-determining switches, since jpeg_set_colorspace sets
* default sampling factors.
*/
} else if (keymatch
(arg
, "scans", 2)) {
/* Set scan script. */
#ifdef C_MULTISCAN_FILES_SUPPORTED
if (++argn
>= argc
) /* advance to next argument */
usage
();
scansarg
= argv
[argn
];
/* We must postpone reading the file in case -progressive appears. */
#else
fprintf(stderr
, "%s: sorry, multi-scan output was not compiled\n",
progname
);
exit(EXIT_FAILURE
);
#endif
} else if (keymatch
(arg
, "smooth", 2)) {
/* Set input smoothing factor. */
int val
;
if (++argn
>= argc
) /* advance to next argument */
usage
();
if (sscanf(argv
[argn
], "%d", &val
) != 1)
usage
();
if (val
< 0 || val
> 100)
usage
();
cinfo
->smoothing_factor
= val
;
} else if (keymatch
(arg
, "targa", 1)) {
/* Input file is Targa format. */
is_targa
= TRUE
;
} else {
usage
(); /* bogus switch */
}
}
/* Post-switch-scanning cleanup */
if (for_real
) {
/* Set quantization tables for selected quality. */
/* Some or all may be overridden if -qtables is present. */
jpeg_set_quality
(cinfo
, quality
, force_baseline
);
if (qtablefile
!= NULL
) /* process -qtables if it was present */
if (! read_quant_tables
(cinfo
, qtablefile
,
q_scale_factor
, force_baseline
))
usage
();
if (qslotsarg
!= NULL
) /* process -qslots if it was present */
if (! set_quant_slots
(cinfo
, qslotsarg
))
usage
();
if (samplearg
!= NULL
) /* process -sample if it was present */
if (! set_sample_factors
(cinfo
, samplearg
))
usage
();
#ifdef C_PROGRESSIVE_SUPPORTED
if (simple_progressive
) /* process -progressive; -scans can override */
jpeg_simple_progression
(cinfo
);
#endif
#ifdef C_MULTISCAN_FILES_SUPPORTED
if (scansarg
!= NULL
) /* process -scans if it was present */
if (! read_scan_script
(cinfo
, scansarg
))
usage
();
#endif
}
return argn
; /* return index of next arg (file name) */
}
/*
* The main program.
*/
int
main
(int argc
, char **argv
)
{
struct jpeg_compress_struct cinfo
;
struct jpeg_error_mgr jerr
;
#ifdef PROGRESS_REPORT
struct cdjpeg_progress_mgr progress
;
#endif
int file_index
;
cjpeg_source_ptr src_mgr
;
FILE
* input_file
;
FILE
* output_file
;
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
= "cjpeg"; /* in case C library doesn't provide it */
/* Initialize the JPEG compression object with default error handling. */
cinfo.
err = jpeg_std_error
(&jerr
);
jpeg_create_compress
(&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
;
/* Now safe to enable signal catcher. */
#ifdef NEED_SIGNAL_CATCHER
enable_signal_catcher
((j_common_ptr
) &cinfo
);
#endif
/* Initialize JPEG parameters.
* Much of this may be overridden later.
* In particular, we don't yet know the input file's color space,
* but we need to provide some value for jpeg_set_defaults() to work.
*/
cinfo.
in_color_space = JCS_RGB
; /* arbitrary guess */
jpeg_set_defaults
(&cinfo
);
/* 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.
*/
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
/* Figure out the input file format, and set up to read it. */
src_mgr
= select_file_type
(&cinfo
, input_file
);
src_mgr
->input_file
= input_file
;
/* Read the input file header to obtain file size & colorspace. */
(*src_mgr
->start_input
) (&cinfo
, src_mgr
);
/* Now that we know input colorspace, fix colorspace-dependent defaults */
jpeg_default_colorspace
(&cinfo
);
/* Adjust default compression parameters by re-parsing the options */
file_index
= parse_switches
(&cinfo
, argc
, argv
, 0, TRUE
);
/* Specify data destination for compression */
jpeg_stdio_dest
(&cinfo
, output_file
);
/* Start compressor */
jpeg_start_compress
(&cinfo
, TRUE
);
/* Process data */
while (cinfo.
next_scanline < cinfo.
image_height) {
num_scanlines
= (*src_mgr
->get_pixel_rows
) (&cinfo
, src_mgr
);
(void) jpeg_write_scanlines
(&cinfo
, src_mgr
->buffer
, num_scanlines
);
}
/* Finish compression and release memory */
(*src_mgr
->finish_input
) (&cinfo
, src_mgr
);
jpeg_finish_compress
(&cinfo
);
jpeg_destroy_compress
(&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
/* All done. */
exit(jerr.
num_warnings ? EXIT_WARNING
: EXIT_SUCCESS
);
return 0; /* suppress no-return-value warnings */
}