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1
/*
2
 * cjpeg.c
3
 *
4
 * Copyright (C) 1991-1998, Thomas G. Lane.
5
 * This file is part of the Independent JPEG Group's software.
6
 * For conditions of distribution and use, see the accompanying README file.
7
 *
8
 * This file contains a command-line user interface for the JPEG compressor.
9
 * It should work on any system with Unix- or MS-DOS-style command lines.
10
 *
11
 * Two different command line styles are permitted, depending on the
12
 * compile-time switch TWO_FILE_COMMANDLINE:
13
 *	cjpeg [options]  inputfile outputfile
14
 *	cjpeg [options]  [inputfile]
15
 * In the second style, output is always to standard output, which you'd
16
 * normally redirect to a file or pipe to some other program.  Input is
17
 * either from a named file or from standard input (typically redirected).
18
 * The second style is convenient on Unix but is unhelpful on systems that
19
 * don't support pipes.  Also, you MUST use the first style if your system
20
 * doesn't do binary I/O to stdin/stdout.
21
 * To simplify script writing, the "-outfile" switch is provided.  The syntax
22
 *	cjpeg [options]  -outfile outputfile  inputfile
23
 * works regardless of which command line style is used.
24
 */
25

26
#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */
27
#include "jversion.h"		/* for version message */
28

29
#ifdef USE_CCOMMAND		/* command-line reader for Macintosh */
30
#ifdef __MWERKS__
31
#include <SIOUX.h>              /* Metrowerks needs this */
32
#include <console.h>		/* ... and this */
33
#endif
34
#ifdef THINK_C
35
#include <console.h>		/* Think declares it here */
36
#endif
37
#endif
38

39

40
/* Create the add-on message string table. */
41

42
#define JMESSAGE(code,string)	string ,
43

44
static const char * const cdjpeg_message_table[] = {
45
#include "cderror.h"
46
  NULL
47
};
48

49

50
/*
51
 * This routine determines what format the input file is,
52
 * and selects the appropriate input-reading module.
53
 *
54
 * To determine which family of input formats the file belongs to,
55
 * we may look only at the first byte of the file, since C does not
56
 * guarantee that more than one character can be pushed back with ungetc.
57
 * Looking at additional bytes would require one of these approaches:
58
 *     1) assume we can fseek() the input file (fails for piped input);
59
 *     2) assume we can push back more than one character (works in
60
 *        some C implementations, but unportable);
61
 *     3) provide our own buffering (breaks input readers that want to use
62
 *        stdio directly, such as the RLE library);
63
 * or  4) don't put back the data, and modify the input_init methods to assume
64
 *        they start reading after the start of file (also breaks RLE library).
65
 * #1 is attractive for MS-DOS but is untenable on Unix.
66
 *
67
 * The most portable solution for file types that can't be identified by their
68
 * first byte is to make the user tell us what they are.  This is also the
69
 * only approach for "raw" file types that contain only arbitrary values.
70
 * We presently apply this method for Targa files.  Most of the time Targa
71
 * files start with 0x00, so we recognize that case.  Potentially, however,
72
 * a Targa file could start with any byte value (byte 0 is the length of the
73
 * seldom-used ID field), so we provide a switch to force Targa input mode.
74
 */
75

76
static boolean is_targa;	/* records user -targa switch */
77

78

79
LOCAL(cjpeg_source_ptr)
80
select_file_type (j_compress_ptr cinfo, FILE * infile)
81
{
82
  int c;
83

84
  if (is_targa) {
85
#ifdef TARGA_SUPPORTED
86
    return jinit_read_targa(cinfo);
87
#else
88
    ERREXIT(cinfo, JERR_TGA_NOTCOMP);
89
#endif
90
  }
91

92
  if ((c = getc(infile)) == EOF)
93
    ERREXIT(cinfo, JERR_INPUT_EMPTY);
94
  if (ungetc(c, infile) == EOF)
95
    ERREXIT(cinfo, JERR_UNGETC_FAILED);
96

97
  switch (c) {
98
#ifdef BMP_SUPPORTED
99
  case 'B':
100
    return jinit_read_bmp(cinfo);
101
#endif
102
#ifdef GIF_SUPPORTED
103
  case 'G':
104
    return jinit_read_gif(cinfo);
105
#endif
106
#ifdef PPM_SUPPORTED
107
  case 'P':
108
    return jinit_read_ppm(cinfo);
109
#endif
110
#ifdef RLE_SUPPORTED
111
  case 'R':
112
    return jinit_read_rle(cinfo);
113
#endif
114
#ifdef TARGA_SUPPORTED
115
  case 0x00:
116
    return jinit_read_targa(cinfo);
117
#endif
118
  default:
119
    ERREXIT(cinfo, JERR_UNKNOWN_FORMAT);
120
    break;
121
  }
122

123
  return NULL;			/* suppress compiler warnings */
124
}
125

126

127
/*
128
 * Argument-parsing code.
129
 * The switch parser is designed to be useful with DOS-style command line
130
 * syntax, ie, intermixed switches and file names, where only the switches
131
 * to the left of a given file name affect processing of that file.
132
 * The main program in this file doesn't actually use this capability...
133
 */
134

135

136
static const char * progname;	/* program name for error messages */
137
static char * outfilename;	/* for -outfile switch */
138

139

140
LOCAL(void)
141
usage (void)
142
/* complain about bad command line */
143
{
144
  fprintf(stderr, "usage: %s [switches] ", progname);
145
#ifdef TWO_FILE_COMMANDLINE
146
  fprintf(stderr, "inputfile outputfile\n");
147
#else
148
  fprintf(stderr, "[inputfile]\n");
149
#endif
150

151
  fprintf(stderr, "Switches (names may be abbreviated):\n");
152
  fprintf(stderr, "  -quality N     Compression quality (0..100; 5-95 is useful range)\n");
153
  fprintf(stderr, "  -grayscale     Create monochrome JPEG file\n");
154
#ifdef ENTROPY_OPT_SUPPORTED
155
  fprintf(stderr, "  -optimize      Optimize Huffman table (smaller file, but slow compression)\n");
156
#endif
157
#ifdef C_PROGRESSIVE_SUPPORTED
158
  fprintf(stderr, "  -progressive   Create progressive JPEG file\n");
159
#endif
160
#ifdef TARGA_SUPPORTED
161
  fprintf(stderr, "  -targa         Input file is Targa format (usually not needed)\n");
162
#endif
163
  fprintf(stderr, "Switches for advanced users:\n");
164
#ifdef DCT_ISLOW_SUPPORTED
165
  fprintf(stderr, "  -dct int       Use integer DCT method%s\n",
166
	  (JDCT_DEFAULT == JDCT_ISLOW ? " (default)" : ""));
167
#endif
168
#ifdef DCT_IFAST_SUPPORTED
169
  fprintf(stderr, "  -dct fast      Use fast integer DCT (less accurate)%s\n",
170
	  (JDCT_DEFAULT == JDCT_IFAST ? " (default)" : ""));
171
#endif
172
#ifdef DCT_FLOAT_SUPPORTED
173
  fprintf(stderr, "  -dct float     Use floating-point DCT method%s\n",
174
	  (JDCT_DEFAULT == JDCT_FLOAT ? " (default)" : ""));
175
#endif
176
  fprintf(stderr, "  -restart N     Set restart interval in rows, or in blocks with B\n");
177
#ifdef INPUT_SMOOTHING_SUPPORTED
178
  fprintf(stderr, "  -smooth N      Smooth dithered input (N=1..100 is strength)\n");
179
#endif
180
  fprintf(stderr, "  -maxmemory N   Maximum memory to use (in kbytes)\n");
181
  fprintf(stderr, "  -outfile name  Specify name for output file\n");
182
  fprintf(stderr, "  -verbose  or  -debug   Emit debug output\n");
183
  fprintf(stderr, "Switches for wizards:\n");
184
#ifdef C_ARITH_CODING_SUPPORTED
185
  fprintf(stderr, "  -arithmetic    Use arithmetic coding\n");
186
#endif
187
  fprintf(stderr, "  -baseline      Force baseline quantization tables\n");
188
  fprintf(stderr, "  -qtables file  Use quantization tables given in file\n");
189
  fprintf(stderr, "  -qslots N[,...]    Set component quantization tables\n");
190
  fprintf(stderr, "  -sample HxV[,...]  Set component sampling factors\n");
191
#ifdef C_MULTISCAN_FILES_SUPPORTED
192
  fprintf(stderr, "  -scans file    Create multi-scan JPEG per script file\n");
193
#endif
194
  exit(EXIT_FAILURE);
195
}
196

197

198
LOCAL(int)
199
parse_switches (j_compress_ptr cinfo, int argc, char **argv,
200
		int last_file_arg_seen, boolean for_real)
201
/* Parse optional switches.
202
 * Returns argv[] index of first file-name argument (== argc if none).
203
 * Any file names with indexes <= last_file_arg_seen are ignored;
204
 * they have presumably been processed in a previous iteration.
205
 * (Pass 0 for last_file_arg_seen on the first or only iteration.)
206
 * for_real is FALSE on the first (dummy) pass; we may skip any expensive
207
 * processing.
208
 */
209
{
210
  int argn;
211
  char * arg;
212
  int quality;			/* -quality parameter */
213
  int q_scale_factor;		/* scaling percentage for -qtables */
214
  boolean force_baseline;
215
  boolean simple_progressive;
216
  char * qtablefile = NULL;	/* saves -qtables filename if any */
217
  char * qslotsarg = NULL;	/* saves -qslots parm if any */
218
  char * samplearg = NULL;	/* saves -sample parm if any */
219
  char * scansarg = NULL;	/* saves -scans parm if any */
220

221
  /* Set up default JPEG parameters. */
222
  /* Note that default -quality level need not, and does not,
223
   * match the default scaling for an explicit -qtables argument.
224
   */
225
  quality = 75;			/* default -quality value */
226
  q_scale_factor = 100;		/* default to no scaling for -qtables */
227
  force_baseline = FALSE;	/* by default, allow 16-bit quantizers */
228
  simple_progressive = FALSE;
229
  is_targa = FALSE;
230
  outfilename = NULL;
231
  cinfo->err->trace_level = 0;
232

233
  /* Scan command line options, adjust parameters */
234

235
  for (argn = 1; argn < argc; argn++) {
236
    arg = argv[argn];
237
    if (*arg != '-') {
238
      /* Not a switch, must be a file name argument */
239
      if (argn <= last_file_arg_seen) {
240
	outfilename = NULL;	/* -outfile applies to just one input file */
241
	continue;		/* ignore this name if previously processed */
242
      }
243
      break;			/* else done parsing switches */
244
    }
245
    arg++;			/* advance past switch marker character */
246

247
    if (keymatch(arg, "arithmetic", 1)) {
248
      /* Use arithmetic coding. */
249
#ifdef C_ARITH_CODING_SUPPORTED
250
      cinfo->arith_code = TRUE;
251
#else
252
      fprintf(stderr, "%s: sorry, arithmetic coding not supported\n",
253
	      progname);
254
      exit(EXIT_FAILURE);
255
#endif
256

257
    } else if (keymatch(arg, "baseline", 1)) {
258
      /* Force baseline-compatible output (8-bit quantizer values). */
259
      force_baseline = TRUE;
260

261
    } else if (keymatch(arg, "dct", 2)) {
262
      /* Select DCT algorithm. */
263
      if (++argn >= argc)	/* advance to next argument */
264
	usage();
265
      if (keymatch(argv[argn], "int", 1)) {
266
	cinfo->dct_method = JDCT_ISLOW;
267
      } else if (keymatch(argv[argn], "fast", 2)) {
268
	cinfo->dct_method = JDCT_IFAST;
269
      } else if (keymatch(argv[argn], "float", 2)) {
270
	cinfo->dct_method = JDCT_FLOAT;
271
      } else
272
	usage();
273

274
    } else if (keymatch(arg, "debug", 1) || keymatch(arg, "verbose", 1)) {
275
      /* Enable debug printouts. */
276
      /* On first -d, print version identification */
277
      static boolean printed_version = FALSE;
278

279
      if (! printed_version) {
280
	fprintf(stderr, "Independent JPEG Group's CJPEG, version %s\n%s\n",
281
		JVERSION, JCOPYRIGHT);
282
	printed_version = TRUE;
283
      }
284
      cinfo->err->trace_level++;
285

286
    } else if (keymatch(arg, "grayscale", 2) || keymatch(arg, "greyscale",2)) {
287
      /* Force a monochrome JPEG file to be generated. */
288
      jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);
289

290
    } else if (keymatch(arg, "maxmemory", 3)) {
291
      /* Maximum memory in Kb (or Mb with 'm'). */
292
      long lval;
293
      char ch = 'x';
294

295
      if (++argn >= argc)	/* advance to next argument */
296
	usage();
297
      if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)
298
	usage();
299
      if (ch == 'm' || ch == 'M')
300
	lval *= 1000L;
301
      cinfo->mem->max_memory_to_use = lval * 1000L;
302

303
    } else if (keymatch(arg, "optimize", 1) || keymatch(arg, "optimise", 1)) {
304
      /* Enable entropy parm optimization. */
305
#ifdef ENTROPY_OPT_SUPPORTED
306
      cinfo->optimize_coding = TRUE;
307
#else
308
      fprintf(stderr, "%s: sorry, entropy optimization was not compiled\n",
309
	      progname);
310
      exit(EXIT_FAILURE);
311
#endif
312

313
    } else if (keymatch(arg, "outfile", 4)) {
314
      /* Set output file name. */
315
      if (++argn >= argc)	/* advance to next argument */
316
	usage();
317
      outfilename = argv[argn];	/* save it away for later use */
318

319
    } else if (keymatch(arg, "progressive", 1)) {
320
      /* Select simple progressive mode. */
321
#ifdef C_PROGRESSIVE_SUPPORTED
322
      simple_progressive = TRUE;
323
      /* We must postpone execution until num_components is known. */
324
#else
325
      fprintf(stderr, "%s: sorry, progressive output was not compiled\n",
326
	      progname);
327
      exit(EXIT_FAILURE);
328
#endif
329

330
    } else if (keymatch(arg, "quality", 1)) {
331
      /* Quality factor (quantization table scaling factor). */
332
      if (++argn >= argc)	/* advance to next argument */
333
	usage();
334
      if (sscanf(argv[argn], "%d", &quality) != 1)
335
	usage();
336
      /* Change scale factor in case -qtables is present. */
337
      q_scale_factor = jpeg_quality_scaling(quality);
338

339
    } else if (keymatch(arg, "qslots", 2)) {
340
      /* Quantization table slot numbers. */
341
      if (++argn >= argc)	/* advance to next argument */
342
	usage();
343
      qslotsarg = argv[argn];
344
      /* Must delay setting qslots until after we have processed any
345
       * colorspace-determining switches, since jpeg_set_colorspace sets
346
       * default quant table numbers.
347
       */
348

349
    } else if (keymatch(arg, "qtables", 2)) {
350
      /* Quantization tables fetched from file. */
351
      if (++argn >= argc)	/* advance to next argument */
352
	usage();
353
      qtablefile = argv[argn];
354
      /* We postpone actually reading the file in case -quality comes later. */
355

356
    } else if (keymatch(arg, "restart", 1)) {
357
      /* Restart interval in MCU rows (or in MCUs with 'b'). */
358
      long lval;
359
      char ch = 'x';
360

361
      if (++argn >= argc)	/* advance to next argument */
362
	usage();
363
      if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)
364
	usage();
365
      if (lval < 0 || lval > 65535L)
366
	usage();
367
      if (ch == 'b' || ch == 'B') {
368
	cinfo->restart_interval = (unsigned int) lval;
369
	cinfo->restart_in_rows = 0; /* else prior '-restart n' overrides me */
370
      } else {
371
	cinfo->restart_in_rows = (int) lval;
372
	/* restart_interval will be computed during startup */
373
      }
374

375
    } else if (keymatch(arg, "sample", 2)) {
376
      /* Set sampling factors. */
377
      if (++argn >= argc)	/* advance to next argument */
378
	usage();
379
      samplearg = argv[argn];
380
      /* Must delay setting sample factors until after we have processed any
381
       * colorspace-determining switches, since jpeg_set_colorspace sets
382
       * default sampling factors.
383
       */
384

385
    } else if (keymatch(arg, "scans", 2)) {
386
      /* Set scan script. */
387
#ifdef C_MULTISCAN_FILES_SUPPORTED
388
      if (++argn >= argc)	/* advance to next argument */
389
	usage();
390
      scansarg = argv[argn];
391
      /* We must postpone reading the file in case -progressive appears. */
392
#else
393
      fprintf(stderr, "%s: sorry, multi-scan output was not compiled\n",
394
	      progname);
395
      exit(EXIT_FAILURE);
396
#endif
397

398
    } else if (keymatch(arg, "smooth", 2)) {
399
      /* Set input smoothing factor. */
400
      int val;
401

402
      if (++argn >= argc)	/* advance to next argument */
403
	usage();
404
      if (sscanf(argv[argn], "%d", &val) != 1)
405
	usage();
406
      if (val < 0 || val > 100)
407
	usage();
408
      cinfo->smoothing_factor = val;
409

410
    } else if (keymatch(arg, "targa", 1)) {
411
      /* Input file is Targa format. */
412
      is_targa = TRUE;
413

414
    } else {
415
      usage();			/* bogus switch */
416
    }
417
  }
418

419
  /* Post-switch-scanning cleanup */
420

421
  if (for_real) {
422

423
    /* Set quantization tables for selected quality. */
424
    /* Some or all may be overridden if -qtables is present. */
425
    jpeg_set_quality(cinfo, quality, force_baseline);
426

427
    if (qtablefile != NULL)	/* process -qtables if it was present */
428
      if (! read_quant_tables(cinfo, qtablefile,
429
			      q_scale_factor, force_baseline))
430
	usage();
431

432
    if (qslotsarg != NULL)	/* process -qslots if it was present */
433
      if (! set_quant_slots(cinfo, qslotsarg))
434
	usage();
435

436
    if (samplearg != NULL)	/* process -sample if it was present */
437
      if (! set_sample_factors(cinfo, samplearg))
438
	usage();
439

440
#ifdef C_PROGRESSIVE_SUPPORTED
441
    if (simple_progressive)	/* process -progressive; -scans can override */
442
      jpeg_simple_progression(cinfo);
443
#endif
444

445
#ifdef C_MULTISCAN_FILES_SUPPORTED
446
    if (scansarg != NULL)	/* process -scans if it was present */
447
      if (! read_scan_script(cinfo, scansarg))
448
	usage();
449
#endif
450
  }
451

452
  return argn;			/* return index of next arg (file name) */
453
}
454

455

456
/*
457
 * The main program.
458
 */
459

460
int
461
main (int argc, char **argv)
462
{
463
  struct jpeg_compress_struct cinfo;
464
  struct jpeg_error_mgr jerr;
465
#ifdef PROGRESS_REPORT
466
  struct cdjpeg_progress_mgr progress;
467
#endif
468
  int file_index;
469
  cjpeg_source_ptr src_mgr;
470
  FILE * input_file;
471
  FILE * output_file;
472
  JDIMENSION num_scanlines;
473

474
  /* On Mac, fetch a command line. */
475
#ifdef USE_CCOMMAND
476
  argc = ccommand(&argv);
477
#endif
478

479
  progname = argv[0];
480
  if (progname == NULL || progname[0] == 0)
481
    progname = "cjpeg";		/* in case C library doesn't provide it */
482

483
  /* Initialize the JPEG compression object with default error handling. */
484
  cinfo.err = jpeg_std_error(&jerr);
485
  jpeg_create_compress(&cinfo);
486
  /* Add some application-specific error messages (from cderror.h) */
487
  jerr.addon_message_table = cdjpeg_message_table;
488
  jerr.first_addon_message = JMSG_FIRSTADDONCODE;
489
  jerr.last_addon_message = JMSG_LASTADDONCODE;
490

491
  /* Now safe to enable signal catcher. */
492
#ifdef NEED_SIGNAL_CATCHER
493
  enable_signal_catcher((j_common_ptr) &cinfo);
494
#endif
495

496
  /* Initialize JPEG parameters.
497
   * Much of this may be overridden later.
498
   * In particular, we don't yet know the input file's color space,
499
   * but we need to provide some value for jpeg_set_defaults() to work.
500
   */
501

502
  cinfo.in_color_space = JCS_RGB; /* arbitrary guess */
503
  jpeg_set_defaults(&cinfo);
504

505
  /* Scan command line to find file names.
506
   * It is convenient to use just one switch-parsing routine, but the switch
507
   * values read here are ignored; we will rescan the switches after opening
508
   * the input file.
509
   */
510

511
  file_index = parse_switches(&cinfo, argc, argv, 0, FALSE);
512

513
#ifdef TWO_FILE_COMMANDLINE
514
  /* Must have either -outfile switch or explicit output file name */
515
  if (outfilename == NULL) {
516
    if (file_index != argc-2) {
517
      fprintf(stderr, "%s: must name one input and one output file\n",
518
	      progname);
519
      usage();
520
    }
521
    outfilename = argv[file_index+1];
522
  } else {
523
    if (file_index != argc-1) {
524
      fprintf(stderr, "%s: must name one input and one output file\n",
525
	      progname);
526
      usage();
527
    }
528
  }
529
#else
530
  /* Unix style: expect zero or one file name */
531
  if (file_index < argc-1) {
532
    fprintf(stderr, "%s: only one input file\n", progname);
533
    usage();
534
  }
535
#endif /* TWO_FILE_COMMANDLINE */
536

537
  /* Open the input file. */
538
  if (file_index < argc) {
539
    if ((input_file = fopen(argv[file_index], READ_BINARY)) == NULL) {
540
      fprintf(stderr, "%s: can't open %s\n", progname, argv[file_index]);
541
      exit(EXIT_FAILURE);
542
    }
543
  } else {
544
    /* default input file is stdin */
545
    input_file = read_stdin();
546
  }
547

548
  /* Open the output file. */
549
  if (outfilename != NULL) {
550
    if ((output_file = fopen(outfilename, WRITE_BINARY)) == NULL) {
551
      fprintf(stderr, "%s: can't open %s\n", progname, outfilename);
552
      exit(EXIT_FAILURE);
553
    }
554
  } else {
555
    /* default output file is stdout */
556
    output_file = write_stdout();
557
  }
558

559
#ifdef PROGRESS_REPORT
560
  start_progress_monitor((j_common_ptr) &cinfo, &progress);
561
#endif
562

563
  /* Figure out the input file format, and set up to read it. */
564
  src_mgr = select_file_type(&cinfo, input_file);
565
  src_mgr->input_file = input_file;
566

567
  /* Read the input file header to obtain file size & colorspace. */
568
  (*src_mgr->start_input) (&cinfo, src_mgr);
569

570
  /* Now that we know input colorspace, fix colorspace-dependent defaults */
571
  jpeg_default_colorspace(&cinfo);
572

573
  /* Adjust default compression parameters by re-parsing the options */
574
  file_index = parse_switches(&cinfo, argc, argv, 0, TRUE);
575

576
  /* Specify data destination for compression */
577
  jpeg_stdio_dest(&cinfo, output_file);
578

579
  /* Start compressor */
580
  jpeg_start_compress(&cinfo, TRUE);
581

582
  /* Process data */
583
  while (cinfo.next_scanline < cinfo.image_height) {
584
    num_scanlines = (*src_mgr->get_pixel_rows) (&cinfo, src_mgr);
585
    (void) jpeg_write_scanlines(&cinfo, src_mgr->buffer, num_scanlines);
586
  }
587

588
  /* Finish compression and release memory */
589
  (*src_mgr->finish_input) (&cinfo, src_mgr);
590
  jpeg_finish_compress(&cinfo);
591
  jpeg_destroy_compress(&cinfo);
592

593
  /* Close files, if we opened them */
594
  if (input_file != stdin)
595
    fclose(input_file);
596
  if (output_file != stdout)
597
    fclose(output_file);
598

599
#ifdef PROGRESS_REPORT
600
  end_progress_monitor((j_common_ptr) &cinfo);
601
#endif
602

603
  /* All done. */
604
  exit(jerr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS);
605
  return 0;			/* suppress no-return-value warnings */
606
}
607

608