libjpeg-turbo/cjpeg.c

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/*
* cjpeg.c
*
* Copyright (C) 1991-1994, 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 */
#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()'s parameter macros */
/* If you have setmode() but not <io.h>, just delete this line: */
#include <io.h> /* to declare setmode() */
#endif
#ifdef USE_CCOMMAND /* command-line reader for Macintosh */
#ifdef __MWERKS__
#include <SIOUX.h> /* Metrowerks declares it here */
#endif
#ifdef THINK_C
#include <console.h> /* Think declares it here */
#endif
#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
#ifndef EXIT_WARNING
#ifdef VMS
#define EXIT_WARNING 1 /* VMS is very nonstandard */
#else
#define EXIT_WARNING 2
#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 */
}
/*
* Signal catcher to ensure that temporary files are removed before aborting.
* NB: for Amiga Manx C this is actually a global routine named _abort();
* we put "#define signal_catcher _abort" in jconfig.h. Talk about bogus...
*/
#ifdef NEED_SIGNAL_CATCHER
static j_common_ptr sig_cinfo;
GLOBAL void
signal_catcher (int signum)
{
if (sig_cinfo != NULL) {
if (sig_cinfo->err != NULL) /* turn off trace output */
sig_cinfo->err->trace_level = 0;
jpeg_destroy(sig_cinfo); /* clean up memory allocation & temp files */
}
exit(EXIT_FAILURE);
}
#endif
/*
* Optional routine to display a percent-done figure on stderr.
*/
#ifdef PROGRESS_REPORT
METHODDEF void
progress_monitor (j_common_ptr cinfo)
{
cd_progress_ptr prog = (cd_progress_ptr) cinfo->progress;
int total_passes = prog->pub.total_passes + prog->total_extra_passes;
int percent_done = (int) (prog->pub.pass_counter*100L/prog->pub.pass_limit);
if (percent_done != prog->percent_done) {
prog->percent_done = percent_done;
if (total_passes > 1) {
fprintf(stderr, "\rPass %d/%d: %3d%% ",
prog->pub.completed_passes + prog->completed_extra_passes + 1,
total_passes, percent_done);
} else {
fprintf(stderr, "\r %3d%% ", percent_done);
}
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 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 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 output\n");
#ifdef C_MULTISCAN_FILES_SUPPORTED
fprintf(stderr, " -nointerleave Create noninterleaved JPEG file\n");
#endif
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");
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
qt_getc (FILE * file)
/* Read next char, skipping over any comments (# to end of line) */
/* A comment/newline sequence is returned as a newline */
{
register int ch;
ch = getc(file);
if (ch == '#') {
do {
ch = getc(file);
} while (ch != '\n' && ch != EOF);
}
return ch;
}
LOCAL long
read_qt_integer (FILE * file)
/* Read an unsigned decimal integer from a quantization-table file */
/* Swallows one trailing character after the integer */
{
register int ch;
register long val;
/* Skip any leading whitespace, detect EOF */
do {
ch = qt_getc(file);
if (ch == EOF)
return EOF;
} while (isspace(ch));
if (! isdigit(ch)) {
fprintf(stderr, "%s: bogus data in quantization file\n", progname);
exit(EXIT_FAILURE);
}
val = ch - '0';
while (ch = qt_getc(file), isdigit(ch)) {
val *= 10;
val += ch - '0';
}
return val;
}
LOCAL void
read_quant_tables (j_compress_ptr cinfo, char * filename, int scale_factor,
boolean force_baseline)
/* Read a set of quantization tables from the specified file.
* The file is plain ASCII text: decimal numbers with whitespace between.
* Comments preceded by '#' may be included in the file.
* There may be one to NUM_QUANT_TBLS tables in the file, each of 64 values.
* The tables are implicitly numbered 0,1,etc.
* NOTE: does not affect the qslots mapping, which will default to selecting
* table 0 for luminance (or primary) components, 1 for chrominance components.
* You must use -qslots if you want a different component->table mapping.
*/
{
/* ZIG[i] is the zigzag-order position of the i'th element of a DCT block */
/* read in natural order (left to right, top to bottom). */
static const int ZIG[DCTSIZE2] = {
0, 1, 5, 6, 14, 15, 27, 28,
2, 4, 7, 13, 16, 26, 29, 42,
3, 8, 12, 17, 25, 30, 41, 43,
9, 11, 18, 24, 31, 40, 44, 53,
10, 19, 23, 32, 39, 45, 52, 54,
20, 22, 33, 38, 46, 51, 55, 60,
21, 34, 37, 47, 50, 56, 59, 61,
35, 36, 48, 49, 57, 58, 62, 63
};
FILE * fp;
int tblno, i;
long val;
unsigned int table[DCTSIZE2];
if ((fp = fopen(filename, "r")) == NULL) {
fprintf(stderr, "%s: can't open %s\n", progname, filename);
exit(EXIT_FAILURE);
}
tblno = 0;
while ((val = read_qt_integer(fp)) != EOF) { /* read 1st element of table */
if (tblno >= NUM_QUANT_TBLS) {
fprintf(stderr, "%s: too many tables in file %s\n", progname, filename);
exit(EXIT_FAILURE);
}
table[0] = (unsigned int) val;
for (i = 1; i < DCTSIZE2; i++) {
if ((val = read_qt_integer(fp)) == EOF) {
fprintf(stderr, "%s: incomplete table in file %s\n", progname, filename);
exit(EXIT_FAILURE);
}
table[ZIG[i]] = (unsigned int) val;
}
jpeg_add_quant_table(cinfo, tblno, table, scale_factor, force_baseline);
tblno++;
}
fclose(fp);
}
LOCAL void
set_quant_slots (j_compress_ptr cinfo, char *arg)
/* Process a quantization-table-selectors parameter string, of the form
* N[,N,...]
* If there are more components than parameters, the last value is replicated.
*/
{
int val = 0; /* default table # */
int ci;
char ch;
for (ci = 0; ci < MAX_COMPONENTS; ci++) {
if (*arg) {
ch = ','; /* if not set by sscanf, will be ',' */
if (sscanf(arg, "%d%c", &val, &ch) < 1)
usage();
if (ch != ',')
usage(); /* syntax check */
if (val < 0 || val >= NUM_QUANT_TBLS) {
fprintf(stderr, "JPEG quantization tables are numbered 0..%d\n",
NUM_QUANT_TBLS-1);
exit(EXIT_FAILURE);
}
cinfo->comp_info[ci].quant_tbl_no = val;
while (*arg && *arg++ != ',') /* advance to next segment of arg string */
;
} else {
/* reached end of parameter, set remaining components to last table */
cinfo->comp_info[ci].quant_tbl_no = val;
}
}
}
LOCAL void
set_sample_factors (j_compress_ptr cinfo, char *arg)
/* Process a sample-factors parameter string, of the form
* HxV[,HxV,...]
* If there are more components than parameters, "1x1" is assumed.
*/
{
int ci, val1, val2;
char ch1, ch2;
for (ci = 0; ci < MAX_COMPONENTS; ci++) {
if (*arg) {
ch2 = ','; /* if not set by sscanf, will be ',' */
if (sscanf(arg, "%d%c%d%c", &val1, &ch1, &val2, &ch2) < 3)
usage();
if ((ch1 != 'x' && ch1 != 'X') || ch2 != ',')
usage(); /* syntax check */
if (val1 <= 0 || val1 > 4 || val2 <= 0 || val2 > 4) {
fprintf(stderr, "JPEG sampling factors must be 1..4\n");
exit(EXIT_FAILURE);
}
cinfo->comp_info[ci].h_samp_factor = val1;
cinfo->comp_info[ci].v_samp_factor = val2;
while (*arg && *arg++ != ',') /* advance to next segment of arg string */
;
} else {
/* reached end of parameter, set remaining components to 1x1 sampling */
cinfo->comp_info[ci].h_samp_factor = 1;
cinfo->comp_info[ci].v_samp_factor = 1;
}
}
}
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;
char * qtablefile = NULL; /* saves -qtables filename if any */
char * qslotsarg = NULL; /* saves -qslots parm if any */
char * samplearg = NULL; /* saves -sample 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 */
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 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, "nointerleave", 3)) {
/* Create noninterleaved file. */
#ifdef C_MULTISCAN_FILES_SUPPORTED
cinfo->interleave = FALSE;
#else
fprintf(stderr, "%s: sorry, multiple-scan support was not compiled\n",
progname);
exit(EXIT_FAILURE);
#endif
} 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, "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, "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 */
read_quant_tables(cinfo, qtablefile, q_scale_factor, force_baseline);
if (qslotsarg != NULL) /* process -qslots if it was present */
set_quant_slots(cinfo, qslotsarg);
if (samplearg != NULL) /* process -sample if it was present */
set_sample_factors(cinfo, samplearg);
}
return argn; /* return index of next arg (file name) */
}
/*
* The main program.
*/
GLOBAL 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
sig_cinfo = (j_common_ptr) &cinfo;
signal(SIGINT, signal_catcher);
#ifdef SIGTERM /* not all systems have SIGTERM */
signal(SIGTERM, signal_catcher);
#endif
#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 */
#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 ((input_file = fdopen(fileno(stdin), READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open stdin\n", progname);
exit(EXIT_FAILURE);
}
#else
input_file = stdin;
#endif
}
/* 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 */
#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 ((output_file = fdopen(fileno(stdout), WRITE_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open stdout\n", progname);
exit(EXIT_FAILURE);
}
#else
output_file = stdout;
#endif
}
#ifdef PROGRESS_REPORT
/* Enable progress display, unless trace output is on */
if (jerr.trace_level == 0) {
progress.pub.progress_monitor = progress_monitor;
progress.completed_extra_passes = 0;
progress.total_extra_passes = 0;
progress.percent_done = -1;
cinfo.progress = &progress.pub;
}
#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
/* Clear away progress display */
if (jerr.trace_level == 0) {
fprintf(stderr, "\r \r");
fflush(stderr);
}
#endif
/* All done. */
exit(jerr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS);
return 0; /* suppress no-return-value warnings */
}