dll/3rdparty/libjpeg/cjpeg.c

   1 /*
   2  * cjpeg.c
   3  *
   4  * Copyright (C) 1991-1998, Thomas G. Lane.
   5  * Modified 2003-2013 by Guido Vollbeding.
   6  * This file is part of the Independent JPEG Group's software.
   7  * For conditions of distribution and use, see the accompanying README file.
   8  *
   9  * This file contains a command-line user interface for the JPEG compressor.
  10  * It should work on any system with Unix- or MS-DOS-style command lines.
  11  *
  12  * Two different command line styles are permitted, depending on the
  13  * compile-time switch TWO_FILE_COMMANDLINE:
  14  *      cjpeg [options]  inputfile outputfile
  15  *      cjpeg [options]  [inputfile]
  16  * In the second style, output is always to standard output, which you'd
  17  * normally redirect to a file or pipe to some other program.  Input is
  18  * either from a named file or from standard input (typically redirected).
  19  * The second style is convenient on Unix but is unhelpful on systems that
  20  * don't support pipes.  Also, you MUST use the first style if your system
  21  * doesn't do binary I/O to stdin/stdout.
  22  * To simplify script writing, the "-outfile" switch is provided.  The syntax
  23  *      cjpeg [options]  -outfile outputfile  inputfile
  24  * works regardless of which command line style is used.
  25  */
  26
  27 #include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */
  28 #include "jversion.h"           /* for version message */
  29
  30 #ifdef USE_CCOMMAND             /* command-line reader for Macintosh */
  31 #ifdef __MWERKS__
  32 #include <SIOUX.h>              /* Metrowerks needs this */
  33 #include <console.h>            /* ... and this */
  34 #endif
  35 #ifdef THINK_C
  36 #include <console.h>            /* Think declares it here */
  37 #endif
  38 #endif
  39
  40
  41 /* Create the add-on message string table. */
  42
  43 #define JMESSAGE(code,string)   string ,
  44
  45 static const char * const cdjpeg_message_table[] = {
  46 #include "cderror.h"
  47   NULL
  48 };
  49
  50
  51 /*
  52  * This routine determines what format the input file is,
  53  * and selects the appropriate input-reading module.
  54  *
  55  * To determine which family of input formats the file belongs to,
  56  * we may look only at the first byte of the file, since C does not
  57  * guarantee that more than one character can be pushed back with ungetc.
  58  * Looking at additional bytes would require one of these approaches:
  59  *     1) assume we can fseek() the input file (fails for piped input);
  60  *     2) assume we can push back more than one character (works in
  61  *        some C implementations, but unportable);
  62  *     3) provide our own buffering (breaks input readers that want to use
  63  *        stdio directly, such as the RLE library);
  64  * or  4) don't put back the data, and modify the input_init methods to assume
  65  *        they start reading after the start of file (also breaks RLE library).
  66  * #1 is attractive for MS-DOS but is untenable on Unix.
  67  *
  68  * The most portable solution for file types that can't be identified by their
  69  * first byte is to make the user tell us what they are.  This is also the
  70  * only approach for "raw" file types that contain only arbitrary values.
  71  * We presently apply this method for Targa files.  Most of the time Targa
  72  * files start with 0x00, so we recognize that case.  Potentially, however,
  73  * a Targa file could start with any byte value (byte 0 is the length of the
  74  * seldom-used ID field), so we provide a switch to force Targa input mode.
  75  */
  76
  77 static boolean is_targa;        /* records user -targa switch */
  78
  79
  80 LOCAL(cjpeg_source_ptr)
  81 select_file_type (j_compress_ptr cinfo, FILE * infile)
  82 {
  83   int c;
  84
  85   if (is_targa) {
  86 #ifdef TARGA_SUPPORTED
  87     return jinit_read_targa(cinfo);
  88 #else
  89     ERREXIT(cinfo, JERR_TGA_NOTCOMP);
  90 #endif
  91   }
  92
  93   if ((c = getc(infile)) == EOF)
  94     ERREXIT(cinfo, JERR_INPUT_EMPTY);
  95   if (ungetc(c, infile) == EOF)
  96     ERREXIT(cinfo, JERR_UNGETC_FAILED);
  97
  98   switch (c) {
  99 #ifdef BMP_SUPPORTED
 100   case 'B':
 101     return jinit_read_bmp(cinfo);
 102 #endif
 103 #ifdef GIF_SUPPORTED
 104   case 'G':
 105     return jinit_read_gif(cinfo);
 106 #endif
 107 #ifdef PPM_SUPPORTED
 108   case 'P':
 109     return jinit_read_ppm(cinfo);
 110 #endif
 111 #ifdef RLE_SUPPORTED
 112   case 'R':
 113     return jinit_read_rle(cinfo);
 114 #endif
 115 #ifdef TARGA_SUPPORTED
 116   case 0x00:
 117     return jinit_read_targa(cinfo);
 118 #endif
 119   default:
 120     ERREXIT(cinfo, JERR_UNKNOWN_FORMAT);
 121     break;
 122   }
 123
 124   return NULL;                  /* suppress compiler warnings */
 125 }
 126
 127
 128 /*
 129  * Argument-parsing code.
 130  * The switch parser is designed to be useful with DOS-style command line
 131  * syntax, ie, intermixed switches and file names, where only the switches
 132  * to the left of a given file name affect processing of that file.
 133  * The main program in this file doesn't actually use this capability...
 134  */
 135
 136
 137 static const char * progname;   /* program name for error messages */
 138 static char * outfilename;      /* for -outfile switch */
 139
 140
 141 LOCAL(void)
 142 usage (void)
 143 /* complain about bad command line */
 144 {
 145   fprintf(stderr, "usage: %s [switches] ", progname);
 146 #ifdef TWO_FILE_COMMANDLINE
 147   fprintf(stderr, "inputfile outputfile\n");
 148 #else
 149   fprintf(stderr, "[inputfile]\n");
 150 #endif
 151
 152   fprintf(stderr, "Switches (names may be abbreviated):\n");
 153   fprintf(stderr, "  -quality N[,...]   Compression quality (0..100; 5-95 is useful range)\n");
 154   fprintf(stderr, "  -grayscale     Create monochrome JPEG file\n");
 155   fprintf(stderr, "  -rgb           Create RGB JPEG file\n");
 156 #ifdef ENTROPY_OPT_SUPPORTED
 157   fprintf(stderr, "  -optimize      Optimize Huffman table (smaller file, but slow compression)\n");
 158 #endif
 159 #ifdef C_PROGRESSIVE_SUPPORTED
 160   fprintf(stderr, "  -progressive   Create progressive JPEG file\n");
 161 #endif
 162 #ifdef DCT_SCALING_SUPPORTED
 163   fprintf(stderr, "  -scale M/N     Scale image by fraction M/N, eg, 1/2\n");
 164 #endif
 165 #ifdef TARGA_SUPPORTED
 166   fprintf(stderr, "  -targa         Input file is Targa format (usually not needed)\n");
 167 #endif
 168   fprintf(stderr, "Switches for advanced users:\n");
 169 #ifdef C_ARITH_CODING_SUPPORTED
 170   fprintf(stderr, "  -arithmetic    Use arithmetic coding\n");
 171 #endif
 172 #ifdef DCT_SCALING_SUPPORTED
 173   fprintf(stderr, "  -block N       DCT block size (1..16; default is 8)\n");
 174 #endif
 175 #if JPEG_LIB_VERSION_MAJOR >= 9
 176   fprintf(stderr, "  -rgb1          Create RGB JPEG file with reversible color transform\n");
 177   fprintf(stderr, "  -bgycc         Create big gamut YCC JPEG file\n");
 178 #endif
 179 #ifdef DCT_ISLOW_SUPPORTED
 180   fprintf(stderr, "  -dct int       Use integer DCT method%s\n",
 181           (JDCT_DEFAULT == JDCT_ISLOW ? " (default)" : ""));
 182 #endif
 183 #ifdef DCT_IFAST_SUPPORTED
 184   fprintf(stderr, "  -dct fast      Use fast integer DCT (less accurate)%s\n",
 185           (JDCT_DEFAULT == JDCT_IFAST ? " (default)" : ""));
 186 #endif
 187 #ifdef DCT_FLOAT_SUPPORTED
 188   fprintf(stderr, "  -dct float     Use floating-point DCT method%s\n",
 189           (JDCT_DEFAULT == JDCT_FLOAT ? " (default)" : ""));
 190 #endif
 191   fprintf(stderr, "  -nosmooth      Don't use high-quality downsampling\n");
 192   fprintf(stderr, "  -restart N     Set restart interval in rows, or in blocks with B\n");
 193 #ifdef INPUT_SMOOTHING_SUPPORTED
 194   fprintf(stderr, "  -smooth N      Smooth dithered input (N=1..100 is strength)\n");
 195 #endif
 196   fprintf(stderr, "  -maxmemory N   Maximum memory to use (in kbytes)\n");
 197   fprintf(stderr, "  -outfile name  Specify name for output file\n");
 198   fprintf(stderr, "  -verbose  or  -debug   Emit debug output\n");
 199   fprintf(stderr, "Switches for wizards:\n");
 200   fprintf(stderr, "  -baseline      Force baseline quantization tables\n");
 201   fprintf(stderr, "  -qtables file  Use quantization tables given in file\n");
 202   fprintf(stderr, "  -qslots N[,...]    Set component quantization tables\n");
 203   fprintf(stderr, "  -sample HxV[,...]  Set component sampling factors\n");
 204 #ifdef C_MULTISCAN_FILES_SUPPORTED
 205   fprintf(stderr, "  -scans file    Create multi-scan JPEG per script file\n");
 206 #endif
 207   exit(EXIT_FAILURE);
 208 }
 209
 210
 211 LOCAL(int)
 212 parse_switches (j_compress_ptr cinfo, int argc, char **argv,
 213                 int last_file_arg_seen, boolean for_real)
 214 /* Parse optional switches.
 215  * Returns argv[] index of first file-name argument (== argc if none).
 216  * Any file names with indexes <= last_file_arg_seen are ignored;
 217  * they have presumably been processed in a previous iteration.
 218  * (Pass 0 for last_file_arg_seen on the first or only iteration.)
 219  * for_real is FALSE on the first (dummy) pass; we may skip any expensive
 220  * processing.
 221  */
 222 {
 223   int argn;
 224   char * arg;
 225   boolean force_baseline;
 226   boolean simple_progressive;
 227   char * qualityarg = NULL;     /* saves -quality parm if any */
 228   char * qtablefile = NULL;     /* saves -qtables filename if any */
 229   char * qslotsarg = NULL;      /* saves -qslots parm if any */
 230   char * samplearg = NULL;      /* saves -sample parm if any */
 231   char * scansarg = NULL;       /* saves -scans parm if any */
 232
 233   /* Set up default JPEG parameters. */
 234
 235   force_baseline = FALSE;       /* by default, allow 16-bit quantizers */
 236   simple_progressive = FALSE;
 237   is_targa = FALSE;
 238   outfilename = NULL;
 239   cinfo->err->trace_level = 0;
 240
 241   /* Scan command line options, adjust parameters */
 242
 243   for (argn = 1; argn < argc; argn++) {
 244     arg = argv[argn];
 245     if (*arg != '-') {
 246       /* Not a switch, must be a file name argument */
 247       if (argn <= last_file_arg_seen) {
 248         outfilename = NULL;     /* -outfile applies to just one input file */
 249         continue;               /* ignore this name if previously processed */
 250       }
 251       break;                    /* else done parsing switches */
 252     }
 253     arg++;                      /* advance past switch marker character */
 254
 255     if (keymatch(arg, "arithmetic", 1)) {
 256       /* Use arithmetic coding. */
 257 #ifdef C_ARITH_CODING_SUPPORTED
 258       cinfo->arith_code = TRUE;
 259 #else
 260       fprintf(stderr, "%s: sorry, arithmetic coding not supported\n",
 261               progname);
 262       exit(EXIT_FAILURE);
 263 #endif
 264
 265     } else if (keymatch(arg, "baseline", 2)) {
 266       /* Force baseline-compatible output (8-bit quantizer values). */
 267       force_baseline = TRUE;
 268
 269     } else if (keymatch(arg, "block", 2)) {
 270       /* Set DCT block size. */
 271 #if defined DCT_SCALING_SUPPORTED && JPEG_LIB_VERSION_MAJOR >= 8 && \
 272       (JPEG_LIB_VERSION_MAJOR > 8 || JPEG_LIB_VERSION_MINOR >= 3)
 273       int val;
 274
 275       if (++argn >= argc)       /* advance to next argument */
 276         usage();
 277       if (sscanf(argv[argn], "%d", &val) != 1)
 278         usage();
 279       if (val < 1 || val > 16)
 280         usage();
 281       cinfo->block_size = val;
 282 #else
 283       fprintf(stderr, "%s: sorry, block size setting not supported\n",
 284               progname);
 285       exit(EXIT_FAILURE);
 286 #endif
 287
 288     } else if (keymatch(arg, "dct", 2)) {
 289       /* Select DCT algorithm. */
 290       if (++argn >= argc)       /* advance to next argument */
 291         usage();
 292       if (keymatch(argv[argn], "int", 1)) {
 293         cinfo->dct_method = JDCT_ISLOW;
 294       } else if (keymatch(argv[argn], "fast", 2)) {
 295         cinfo->dct_method = JDCT_IFAST;
 296       } else if (keymatch(argv[argn], "float", 2)) {
 297         cinfo->dct_method = JDCT_FLOAT;
 298       } else
 299         usage();
 300
 301     } else if (keymatch(arg, "debug", 1) || keymatch(arg, "verbose", 1)) {
 302       /* Enable debug printouts. */
 303       /* On first -d, print version identification */
 304       static boolean printed_version = FALSE;
 305
 306       if (! printed_version) {
 307         fprintf(stderr, "Independent JPEG Group's CJPEG, version %s\n%s\n",
 308                 JVERSION, JCOPYRIGHT);
 309         printed_version = TRUE;
 310       }
 311       cinfo->err->trace_level++;
 312
 313     } else if (keymatch(arg, "grayscale", 2) || keymatch(arg, "greyscale",2)) {
 314       /* Force a monochrome JPEG file to be generated. */
 315       jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);
 316
 317     } else if (keymatch(arg, "rgb", 3) || keymatch(arg, "rgb1", 4)) {
 318       /* Force an RGB JPEG file to be generated. */
 319 #if JPEG_LIB_VERSION_MAJOR >= 9
 320       /* Note: Entropy table assignment in jpeg_set_colorspace depends
 321        * on color_transform.
 322        */
 323       cinfo->color_transform = arg[3] ? JCT_SUBTRACT_GREEN : JCT_NONE;
 324 #endif
 325       jpeg_set_colorspace(cinfo, JCS_RGB);
 326
 327     } else if (keymatch(arg, "bgycc", 5)) {
 328       /* Force a big gamut YCC JPEG file to be generated. */
 329 #if JPEG_LIB_VERSION_MAJOR >= 9 && \
 330       (JPEG_LIB_VERSION_MAJOR > 9 || JPEG_LIB_VERSION_MINOR >= 1)
 331       jpeg_set_colorspace(cinfo, JCS_BG_YCC);
 332 #else
 333       fprintf(stderr, "%s: sorry, BG_YCC colorspace not supported\n",
 334               progname);
 335       exit(EXIT_FAILURE);
 336 #endif
 337
 338     } else if (keymatch(arg, "maxmemory", 3)) {
 339       /* Maximum memory in Kb (or Mb with 'm'). */
 340       long lval;
 341       char ch = 'x';
 342
 343       if (++argn >= argc)       /* advance to next argument */
 344         usage();
 345       if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)
 346         usage();
 347       if (ch == 'm' || ch == 'M')
 348         lval *= 1000L;
 349       cinfo->mem->max_memory_to_use = lval * 1000L;
 350
 351     } else if (keymatch(arg, "nosmooth", 3)) {
 352       /* Suppress fancy downsampling. */
 353       cinfo->do_fancy_downsampling = FALSE;
 354
 355     } else if (keymatch(arg, "optimize", 1) || keymatch(arg, "optimise", 1)) {
 356       /* Enable entropy parm optimization. */
 357 #ifdef ENTROPY_OPT_SUPPORTED
 358       cinfo->optimize_coding = TRUE;
 359 #else
 360       fprintf(stderr, "%s: sorry, entropy optimization was not compiled\n",
 361               progname);
 362       exit(EXIT_FAILURE);
 363 #endif
 364
 365     } else if (keymatch(arg, "outfile", 4)) {
 366       /* Set output file name. */
 367       if (++argn >= argc)       /* advance to next argument */
 368         usage();
 369       outfilename = argv[argn]; /* save it away for later use */
 370
 371     } else if (keymatch(arg, "progressive", 1)) {
 372       /* Select simple progressive mode. */
 373 #ifdef C_PROGRESSIVE_SUPPORTED
 374       simple_progressive = TRUE;
 375       /* We must postpone execution until num_components is known. */
 376 #else
 377       fprintf(stderr, "%s: sorry, progressive output was not compiled\n",
 378               progname);
 379       exit(EXIT_FAILURE);
 380 #endif
 381
 382     } else if (keymatch(arg, "quality", 1)) {
 383       /* Quality ratings (quantization table scaling factors). */
 384       if (++argn >= argc)       /* advance to next argument */
 385         usage();
 386       qualityarg = argv[argn];
 387
 388     } else if (keymatch(arg, "qslots", 2)) {
 389       /* Quantization table slot numbers. */
 390       if (++argn >= argc)       /* advance to next argument */
 391         usage();
 392       qslotsarg = argv[argn];
 393       /* Must delay setting qslots until after we have processed any
 394        * colorspace-determining switches, since jpeg_set_colorspace sets
 395        * default quant table numbers.
 396        */
 397
 398     } else if (keymatch(arg, "qtables", 2)) {
 399       /* Quantization tables fetched from file. */
 400       if (++argn >= argc)       /* advance to next argument */
 401         usage();
 402       qtablefile = argv[argn];
 403       /* We postpone actually reading the file in case -quality comes later. */
 404
 405     } else if (keymatch(arg, "restart", 1)) {
 406       /* Restart interval in MCU rows (or in MCUs with 'b'). */
 407       long lval;
 408       char ch = 'x';
 409
 410       if (++argn >= argc)       /* advance to next argument */
 411         usage();
 412       if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)
 413         usage();
 414       if (lval < 0 || lval > 65535L)
 415         usage();
 416       if (ch == 'b' || ch == 'B') {
 417         cinfo->restart_interval = (unsigned int) lval;
 418         cinfo->restart_in_rows = 0; /* else prior '-restart n' overrides me */
 419       } else {
 420         cinfo->restart_in_rows = (int) lval;
 421         /* restart_interval will be computed during startup */
 422       }
 423
 424     } else if (keymatch(arg, "sample", 2)) {
 425       /* Set sampling factors. */
 426       if (++argn >= argc)       /* advance to next argument */
 427         usage();
 428       samplearg = argv[argn];
 429       /* Must delay setting sample factors until after we have processed any
 430        * colorspace-determining switches, since jpeg_set_colorspace sets
 431        * default sampling factors.
 432        */
 433
 434     } else if (keymatch(arg, "scale", 4)) {
 435       /* Scale the image by a fraction M/N. */
 436       if (++argn >= argc)       /* advance to next argument */
 437         usage();
 438       if (sscanf(argv[argn], "%u/%u",
 439                  &cinfo->scale_num, &cinfo->scale_denom) != 2)
 440         usage();
 441
 442     } else if (keymatch(arg, "scans", 4)) {
 443       /* Set scan script. */
 444 #ifdef C_MULTISCAN_FILES_SUPPORTED
 445       if (++argn >= argc)       /* advance to next argument */
 446         usage();
 447       scansarg = argv[argn];
 448       /* We must postpone reading the file in case -progressive appears. */
 449 #else
 450       fprintf(stderr, "%s: sorry, multi-scan output was not compiled\n",
 451               progname);
 452       exit(EXIT_FAILURE);
 453 #endif
 454
 455     } else if (keymatch(arg, "smooth", 2)) {
 456       /* Set input smoothing factor. */
 457       int val;
 458
 459       if (++argn >= argc)       /* advance to next argument */
 460         usage();
 461       if (sscanf(argv[argn], "%d", &val) != 1)
 462         usage();
 463       if (val < 0 || val > 100)
 464         usage();
 465       cinfo->smoothing_factor = val;
 466
 467     } else if (keymatch(arg, "targa", 1)) {
 468       /* Input file is Targa format. */
 469       is_targa = TRUE;
 470
 471     } else {
 472       usage();                  /* bogus switch */
 473     }
 474   }
 475
 476   /* Post-switch-scanning cleanup */
 477
 478   if (for_real) {
 479
 480     /* Set quantization tables for selected quality. */
 481     /* Some or all may be overridden if -qtables is present. */
 482     if (qualityarg != NULL)     /* process -quality if it was present */
 483       if (! set_quality_ratings(cinfo, qualityarg, force_baseline))
 484         usage();
 485
 486     if (qtablefile != NULL)     /* process -qtables if it was present */
 487       if (! read_quant_tables(cinfo, qtablefile, force_baseline))
 488         usage();
 489
 490     if (qslotsarg != NULL)      /* process -qslots if it was present */
 491       if (! set_quant_slots(cinfo, qslotsarg))
 492         usage();
 493
 494     if (samplearg != NULL)      /* process -sample if it was present */
 495       if (! set_sample_factors(cinfo, samplearg))
 496         usage();
 497
 498 #ifdef C_PROGRESSIVE_SUPPORTED
 499     if (simple_progressive)     /* process -progressive; -scans can override */
 500       jpeg_simple_progression(cinfo);
 501 #endif
 502
 503 #ifdef C_MULTISCAN_FILES_SUPPORTED
 504     if (scansarg != NULL)       /* process -scans if it was present */
 505       if (! read_scan_script(cinfo, scansarg))
 506         usage();
 507 #endif
 508   }
 509
 510   return argn;                  /* return index of next arg (file name) */
 511 }
 512
 513
 514 /*
 515  * The main program.
 516  */
 517
 518 int
 519 main (int argc, char **argv)
 520 {
 521   struct jpeg_compress_struct cinfo;
 522   struct jpeg_error_mgr jerr;
 523 #ifdef PROGRESS_REPORT
 524   struct cdjpeg_progress_mgr progress;
 525 #endif
 526   int file_index;
 527   cjpeg_source_ptr src_mgr;
 528   FILE * input_file;
 529   FILE * output_file;
 530   JDIMENSION num_scanlines;
 531
 532   /* On Mac, fetch a command line. */
 533 #ifdef USE_CCOMMAND
 534   argc = ccommand(&argv);
 535 #endif
 536
 537   progname = argv[0];
 538   if (progname == NULL || progname[0] == 0)
 539     progname = "cjpeg";         /* in case C library doesn't provide it */
 540
 541   /* Initialize the JPEG compression object with default error handling. */
 542   cinfo.err = jpeg_std_error(&jerr);
 543   jpeg_create_compress(&cinfo);
 544   /* Add some application-specific error messages (from cderror.h) */
 545   jerr.addon_message_table = cdjpeg_message_table;
 546   jerr.first_addon_message = JMSG_FIRSTADDONCODE;
 547   jerr.last_addon_message = JMSG_LASTADDONCODE;
 548
 549   /* Now safe to enable signal catcher. */
 550 #ifdef NEED_SIGNAL_CATCHER
 551   enable_signal_catcher((j_common_ptr) &cinfo);
 552 #endif
 553
 554   /* Initialize JPEG parameters.
 555    * Much of this may be overridden later.
 556    * In particular, we don't yet know the input file's color space,
 557    * but we need to provide some value for jpeg_set_defaults() to work.
 558    */
 559
 560   cinfo.in_color_space = JCS_RGB; /* arbitrary guess */
 561   jpeg_set_defaults(&cinfo);
 562
 563   /* Scan command line to find file names.
 564    * It is convenient to use just one switch-parsing routine, but the switch
 565    * values read here are ignored; we will rescan the switches after opening
 566    * the input file.
 567    */
 568
 569   file_index = parse_switches(&cinfo, argc, argv, 0, FALSE);
 570
 571 #ifdef TWO_FILE_COMMANDLINE
 572   /* Must have either -outfile switch or explicit output file name */
 573   if (outfilename == NULL) {
 574     if (file_index != argc-2) {
 575       fprintf(stderr, "%s: must name one input and one output file\n",
 576               progname);
 577       usage();
 578     }
 579     outfilename = argv[file_index+1];
 580   } else {
 581     if (file_index != argc-1) {
 582       fprintf(stderr, "%s: must name one input and one output file\n",
 583               progname);
 584       usage();
 585     }
 586   }
 587 #else
 588   /* Unix style: expect zero or one file name */
 589   if (file_index < argc-1) {
 590     fprintf(stderr, "%s: only one input file\n", progname);
 591     usage();
 592   }
 593 #endif /* TWO_FILE_COMMANDLINE */
 594
 595   /* Open the input file. */
 596   if (file_index < argc) {
 597     if ((input_file = fopen(argv[file_index], READ_BINARY)) == NULL) {
 598       fprintf(stderr, "%s: can't open %s\n", progname, argv[file_index]);
 599       exit(EXIT_FAILURE);
 600     }
 601   } else {
 602     /* default input file is stdin */
 603     input_file = read_stdin();
 604   }
 605
 606   /* Open the output file. */
 607   if (outfilename != NULL) {
 608     if ((output_file = fopen(outfilename, WRITE_BINARY)) == NULL) {
 609       fprintf(stderr, "%s: can't open %s\n", progname, outfilename);
 610       exit(EXIT_FAILURE);
 611     }
 612   } else {
 613     /* default output file is stdout */
 614     output_file = write_stdout();
 615   }
 616
 617 #ifdef PROGRESS_REPORT
 618   start_progress_monitor((j_common_ptr) &cinfo, &progress);
 619 #endif
 620
 621   /* Figure out the input file format, and set up to read it. */
 622   src_mgr = select_file_type(&cinfo, input_file);
 623   src_mgr->input_file = input_file;
 624
 625   /* Read the input file header to obtain file size & colorspace. */
 626   (*src_mgr->start_input) (&cinfo, src_mgr);
 627
 628   /* Now that we know input colorspace, fix colorspace-dependent defaults */
 629   jpeg_default_colorspace(&cinfo);
 630
 631   /* Adjust default compression parameters by re-parsing the options */
 632   file_index = parse_switches(&cinfo, argc, argv, 0, TRUE);
 633
 634   /* Specify data destination for compression */
 635   jpeg_stdio_dest(&cinfo, output_file);
 636
 637   /* Start compressor */
 638   jpeg_start_compress(&cinfo, TRUE);
 639
 640   /* Process data */
 641   while (cinfo.next_scanline < cinfo.image_height) {
 642     num_scanlines = (*src_mgr->get_pixel_rows) (&cinfo, src_mgr);
 643     (void) jpeg_write_scanlines(&cinfo, src_mgr->buffer, num_scanlines);
 644   }
 645
 646   /* Finish compression and release memory */
 647   (*src_mgr->finish_input) (&cinfo, src_mgr);
 648   jpeg_finish_compress(&cinfo);
 649   jpeg_destroy_compress(&cinfo);
 650
 651   /* Close files, if we opened them */
 652   if (input_file != stdin)
 653     fclose(input_file);
 654   if (output_file != stdout)
 655     fclose(output_file);
 656
 657 #ifdef PROGRESS_REPORT
 658   end_progress_monitor((j_common_ptr) &cinfo);
 659 #endif
 660
 661   /* All done. */
 662   exit(jerr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS);
 663   return 0;                     /* suppress no-return-value warnings */
 664 }