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 } 665