1 /*
2  * djpeg.c
3  *
4  * This file was part of the Independent JPEG Group's software:
5  * Copyright (C) 1991-1997, Thomas G. Lane.
6  * libjpeg-turbo Modifications:
7  * Copyright (C) 2010-2011, 2013-2016, D. R. Commander.
8  * Copyright (C) 2015, Google, Inc.
9  * For conditions of distribution and use, see the accompanying README file.
10  *
11  * This file contains a command-line user interface for the JPEG decompressor.
12  * It should work on any system with Unix- or MS-DOS-style command lines.
13  *
14  * Two different command line styles are permitted, depending on the
15  * compile-time switch TWO_FILE_COMMANDLINE:
16  *      djpeg [options]  inputfile outputfile
17  *      djpeg [options]  [inputfile]
18  * In the second style, output is always to standard output, which you'd
19  * normally redirect to a file or pipe to some other program.  Input is
20  * either from a named file or from standard input (typically redirected).
21  * The second style is convenient on Unix but is unhelpful on systems that
22  * don't support pipes.  Also, you MUST use the first style if your system
23  * doesn't do binary I/O to stdin/stdout.
24  * To simplify script writing, the "-outfile" switch is provided.  The syntax
25  *      djpeg [options]  -outfile outputfile  inputfile
26  * works regardless of which command line style is used.
27  */
28 
29 #include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */
30 #include "jversion.h"           /* for version message */
31 #include "jconfigint.h"
32 #include "wrppm.h"
33 
34 #include <ctype.h>              /* to declare isprint() */
35 
36 #ifdef USE_CCOMMAND             /* command-line reader for Macintosh */
37 #ifdef __MWERKS__
38 #include <SIOUX.h>              /* Metrowerks needs this */
39 #include <console.h>            /* ... and this */
40 #endif
41 #ifdef THINK_C
42 #include <console.h>            /* Think declares it here */
43 #endif
44 #endif
45 
46 
47 /* Create the add-on message string table. */
48 
49 #define JMESSAGE(code,string)   string ,
50 
51 static const char * const cdjpeg_message_table[] = {
52 #include "cderror.h"
53   NULL
54 };
55 
56 
57 /*
58  * This list defines the known output image formats
59  * (not all of which need be supported by a given version).
60  * You can change the default output format by defining DEFAULT_FMT;
61  * indeed, you had better do so if you undefine PPM_SUPPORTED.
62  */
63 
64 typedef enum {
65         FMT_BMP,                /* BMP format (Windows flavor) */
66         FMT_GIF,                /* GIF format */
67         FMT_OS2,                /* BMP format (OS/2 flavor) */
68         FMT_PPM,                /* PPM/PGM (PBMPLUS formats) */
69         FMT_RLE,                /* RLE format */
70         FMT_TARGA,              /* Targa format */
71         FMT_TIFF                /* TIFF format */
72 } IMAGE_FORMATS;
73 
74 #ifndef DEFAULT_FMT             /* so can override from CFLAGS in Makefile */
75 #define DEFAULT_FMT     FMT_PPM
76 #endif
77 
78 static IMAGE_FORMATS requested_fmt;
79 
80 
81 /*
82  * Argument-parsing code.
83  * The switch parser is designed to be useful with DOS-style command line
84  * syntax, ie, intermixed switches and file names, where only the switches
85  * to the left of a given file name affect processing of that file.
86  * The main program in this file doesn't actually use this capability...
87  */
88 
89 
90 static const char *progname;    /* program name for error messages */
91 static char *outfilename;       /* for -outfile switch */
92 boolean memsrc;                 /* for -memsrc switch */
93 boolean skip, crop;
94 JDIMENSION skip_start, skip_end;
95 JDIMENSION crop_x, crop_y, crop_width, crop_height;
96 #define INPUT_BUF_SIZE  4096
97 
98 
99 LOCAL(void)
usage(void)100 usage (void)
101 /* complain about bad command line */
102 {
103   fprintf(stderr, "usage: %s [switches] ", progname);
104 #ifdef TWO_FILE_COMMANDLINE
105   fprintf(stderr, "inputfile outputfile\n");
106 #else
107   fprintf(stderr, "[inputfile]\n");
108 #endif
109 
110   fprintf(stderr, "Switches (names may be abbreviated):\n");
111   fprintf(stderr, "  -colors N      Reduce image to no more than N colors\n");
112   fprintf(stderr, "  -fast          Fast, low-quality processing\n");
113   fprintf(stderr, "  -grayscale     Force grayscale output\n");
114   fprintf(stderr, "  -rgb           Force RGB output\n");
115   fprintf(stderr, "  -rgb565        Force RGB565 output\n");
116 #ifdef IDCT_SCALING_SUPPORTED
117   fprintf(stderr, "  -scale M/N     Scale output image by fraction M/N, eg, 1/8\n");
118 #endif
119 #ifdef BMP_SUPPORTED
120   fprintf(stderr, "  -bmp           Select BMP output format (Windows style)%s\n",
121           (DEFAULT_FMT == FMT_BMP ? " (default)" : ""));
122 #endif
123 #ifdef GIF_SUPPORTED
124   fprintf(stderr, "  -gif           Select GIF output format%s\n",
125           (DEFAULT_FMT == FMT_GIF ? " (default)" : ""));
126 #endif
127 #ifdef BMP_SUPPORTED
128   fprintf(stderr, "  -os2           Select BMP output format (OS/2 style)%s\n",
129           (DEFAULT_FMT == FMT_OS2 ? " (default)" : ""));
130 #endif
131 #ifdef PPM_SUPPORTED
132   fprintf(stderr, "  -pnm           Select PBMPLUS (PPM/PGM) output format%s\n",
133           (DEFAULT_FMT == FMT_PPM ? " (default)" : ""));
134 #endif
135 #ifdef RLE_SUPPORTED
136   fprintf(stderr, "  -rle           Select Utah RLE output format%s\n",
137           (DEFAULT_FMT == FMT_RLE ? " (default)" : ""));
138 #endif
139 #ifdef TARGA_SUPPORTED
140   fprintf(stderr, "  -targa         Select Targa output format%s\n",
141           (DEFAULT_FMT == FMT_TARGA ? " (default)" : ""));
142 #endif
143   fprintf(stderr, "Switches for advanced users:\n");
144 #ifdef DCT_ISLOW_SUPPORTED
145   fprintf(stderr, "  -dct int       Use integer DCT method%s\n",
146           (JDCT_DEFAULT == JDCT_ISLOW ? " (default)" : ""));
147 #endif
148 #ifdef DCT_IFAST_SUPPORTED
149   fprintf(stderr, "  -dct fast      Use fast integer DCT (less accurate)%s\n",
150           (JDCT_DEFAULT == JDCT_IFAST ? " (default)" : ""));
151 #endif
152 #ifdef DCT_FLOAT_SUPPORTED
153   fprintf(stderr, "  -dct float     Use floating-point DCT method%s\n",
154           (JDCT_DEFAULT == JDCT_FLOAT ? " (default)" : ""));
155 #endif
156   fprintf(stderr, "  -dither fs     Use F-S dithering (default)\n");
157   fprintf(stderr, "  -dither none   Don't use dithering in quantization\n");
158   fprintf(stderr, "  -dither ordered  Use ordered dither (medium speed, quality)\n");
159 #ifdef QUANT_2PASS_SUPPORTED
160   fprintf(stderr, "  -map FILE      Map to colors used in named image file\n");
161 #endif
162   fprintf(stderr, "  -nosmooth      Don't use high-quality upsampling\n");
163 #ifdef QUANT_1PASS_SUPPORTED
164   fprintf(stderr, "  -onepass       Use 1-pass quantization (fast, low quality)\n");
165 #endif
166   fprintf(stderr, "  -maxmemory N   Maximum memory to use (in kbytes)\n");
167   fprintf(stderr, "  -outfile name  Specify name for output file\n");
168 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
169   fprintf(stderr, "  -memsrc        Load input file into memory before decompressing\n");
170 #endif
171 
172   fprintf(stderr, "  -skip Y0,Y1    Decompress all rows except those between Y0 and Y1 (inclusive)\n");
173   fprintf(stderr, "  -crop WxH+X+Y  Decompress only a rectangular subregion of the image\n");
174   fprintf(stderr, "  -verbose  or  -debug   Emit debug output\n");
175   fprintf(stderr, "  -version       Print version information and exit\n");
176   exit(EXIT_FAILURE);
177 }
178 
179 
180 LOCAL(int)
parse_switches(j_decompress_ptr cinfo,int argc,char ** argv,int last_file_arg_seen,boolean for_real)181 parse_switches (j_decompress_ptr cinfo, int argc, char **argv,
182                 int last_file_arg_seen, boolean for_real)
183 /* Parse optional switches.
184  * Returns argv[] index of first file-name argument (== argc if none).
185  * Any file names with indexes <= last_file_arg_seen are ignored;
186  * they have presumably been processed in a previous iteration.
187  * (Pass 0 for last_file_arg_seen on the first or only iteration.)
188  * for_real is FALSE on the first (dummy) pass; we may skip any expensive
189  * processing.
190  */
191 {
192   int argn;
193   char * arg;
194 
195   /* Set up default JPEG parameters. */
196   requested_fmt = DEFAULT_FMT;  /* set default output file format */
197   outfilename = NULL;
198   memsrc = FALSE;
199   skip = FALSE;
200   crop = FALSE;
201   cinfo->err->trace_level = 0;
202 
203   /* Scan command line options, adjust parameters */
204 
205   for (argn = 1; argn < argc; argn++) {
206     arg = argv[argn];
207     if (*arg != '-') {
208       /* Not a switch, must be a file name argument */
209       if (argn <= last_file_arg_seen) {
210         outfilename = NULL;     /* -outfile applies to just one input file */
211         continue;               /* ignore this name if previously processed */
212       }
213       break;                    /* else done parsing switches */
214     }
215     arg++;                      /* advance past switch marker character */
216 
217     if (keymatch(arg, "bmp", 1)) {
218       /* BMP output format. */
219       requested_fmt = FMT_BMP;
220 
221     } else if (keymatch(arg, "colors", 1) || keymatch(arg, "colours", 1) ||
222                keymatch(arg, "quantize", 1) || keymatch(arg, "quantise", 1)) {
223       /* Do color quantization. */
224       int val;
225 
226       if (++argn >= argc)       /* advance to next argument */
227         usage();
228       if (sscanf(argv[argn], "%d", &val) != 1)
229         usage();
230       cinfo->desired_number_of_colors = val;
231       cinfo->quantize_colors = TRUE;
232 
233     } else if (keymatch(arg, "dct", 2)) {
234       /* Select IDCT algorithm. */
235       if (++argn >= argc)       /* advance to next argument */
236         usage();
237       if (keymatch(argv[argn], "int", 1)) {
238         cinfo->dct_method = JDCT_ISLOW;
239       } else if (keymatch(argv[argn], "fast", 2)) {
240         cinfo->dct_method = JDCT_IFAST;
241       } else if (keymatch(argv[argn], "float", 2)) {
242         cinfo->dct_method = JDCT_FLOAT;
243       } else
244         usage();
245 
246     } else if (keymatch(arg, "dither", 2)) {
247       /* Select dithering algorithm. */
248       if (++argn >= argc)       /* advance to next argument */
249         usage();
250       if (keymatch(argv[argn], "fs", 2)) {
251         cinfo->dither_mode = JDITHER_FS;
252       } else if (keymatch(argv[argn], "none", 2)) {
253         cinfo->dither_mode = JDITHER_NONE;
254       } else if (keymatch(argv[argn], "ordered", 2)) {
255         cinfo->dither_mode = JDITHER_ORDERED;
256       } else
257         usage();
258 
259     } else if (keymatch(arg, "debug", 1) || keymatch(arg, "verbose", 1)) {
260       /* Enable debug printouts. */
261       /* On first -d, print version identification */
262       static boolean printed_version = FALSE;
263 
264       if (! printed_version) {
265         fprintf(stderr, "%s version %s (build %s)\n",
266                 PACKAGE_NAME, VERSION, BUILD);
267         fprintf(stderr, "%s\n\n", JCOPYRIGHT);
268         fprintf(stderr, "Emulating The Independent JPEG Group's software, version %s\n\n",
269                 JVERSION);
270         printed_version = TRUE;
271       }
272       cinfo->err->trace_level++;
273 
274     } else if (keymatch(arg, "version", 4)) {
275       fprintf(stderr, "%s version %s (build %s)\n",
276               PACKAGE_NAME, VERSION, BUILD);
277       exit(EXIT_SUCCESS);
278 
279     } else if (keymatch(arg, "fast", 1)) {
280       /* Select recommended processing options for quick-and-dirty output. */
281       cinfo->two_pass_quantize = FALSE;
282       cinfo->dither_mode = JDITHER_ORDERED;
283       if (! cinfo->quantize_colors) /* don't override an earlier -colors */
284         cinfo->desired_number_of_colors = 216;
285       cinfo->dct_method = JDCT_FASTEST;
286       cinfo->do_fancy_upsampling = FALSE;
287 
288     } else if (keymatch(arg, "gif", 1)) {
289       /* GIF output format. */
290       requested_fmt = FMT_GIF;
291 
292     } else if (keymatch(arg, "grayscale", 2) || keymatch(arg, "greyscale",2)) {
293       /* Force monochrome output. */
294       cinfo->out_color_space = JCS_GRAYSCALE;
295 
296     } else if (keymatch(arg, "rgb", 2)) {
297       /* Force RGB output. */
298       cinfo->out_color_space = JCS_RGB;
299 
300     } else if (keymatch(arg, "rgb565", 2)) {
301       /* Force RGB565 output. */
302       cinfo->out_color_space = JCS_RGB565;
303 
304     } else if (keymatch(arg, "map", 3)) {
305       /* Quantize to a color map taken from an input file. */
306       if (++argn >= argc)       /* advance to next argument */
307         usage();
308       if (for_real) {           /* too expensive to do twice! */
309 #ifdef QUANT_2PASS_SUPPORTED    /* otherwise can't quantize to supplied map */
310         FILE * mapfile;
311 
312         if ((mapfile = fopen(argv[argn], READ_BINARY)) == NULL) {
313           fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]);
314           exit(EXIT_FAILURE);
315         }
316         read_color_map(cinfo, mapfile);
317         fclose(mapfile);
318         cinfo->quantize_colors = TRUE;
319 #else
320         ERREXIT(cinfo, JERR_NOT_COMPILED);
321 #endif
322       }
323 
324     } else if (keymatch(arg, "maxmemory", 3)) {
325       /* Maximum memory in Kb (or Mb with 'm'). */
326       long lval;
327       char ch = 'x';
328 
329       if (++argn >= argc)       /* advance to next argument */
330         usage();
331       if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)
332         usage();
333       if (ch == 'm' || ch == 'M')
334         lval *= 1000L;
335       cinfo->mem->max_memory_to_use = lval * 1000L;
336 
337     } else if (keymatch(arg, "nosmooth", 3)) {
338       /* Suppress fancy upsampling */
339       cinfo->do_fancy_upsampling = FALSE;
340 
341     } else if (keymatch(arg, "onepass", 3)) {
342       /* Use fast one-pass quantization. */
343       cinfo->two_pass_quantize = FALSE;
344 
345     } else if (keymatch(arg, "os2", 3)) {
346       /* BMP output format (OS/2 flavor). */
347       requested_fmt = FMT_OS2;
348 
349     } else if (keymatch(arg, "outfile", 4)) {
350       /* Set output file name. */
351       if (++argn >= argc)       /* advance to next argument */
352         usage();
353       outfilename = argv[argn]; /* save it away for later use */
354 
355     } else if (keymatch(arg, "memsrc", 2)) {
356       /* Use in-memory source manager */
357 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
358       memsrc = TRUE;
359 #else
360       fprintf(stderr, "%s: sorry, in-memory source manager was not compiled in\n",
361               progname);
362       exit(EXIT_FAILURE);
363 #endif
364 
365     } else if (keymatch(arg, "pnm", 1) || keymatch(arg, "ppm", 1)) {
366       /* PPM/PGM output format. */
367       requested_fmt = FMT_PPM;
368 
369     } else if (keymatch(arg, "rle", 1)) {
370       /* RLE output format. */
371       requested_fmt = FMT_RLE;
372 
373     } else if (keymatch(arg, "scale", 2)) {
374       /* Scale the output image by a fraction M/N. */
375       if (++argn >= argc)       /* advance to next argument */
376         usage();
377       if (sscanf(argv[argn], "%d/%d",
378                  &cinfo->scale_num, &cinfo->scale_denom) != 2)
379         usage();
380 
381     } else if (keymatch(arg, "skip", 2)) {
382       if (++argn >= argc)
383         usage();
384       if (sscanf(argv[argn], "%u,%u", &skip_start, &skip_end) != 2 ||
385           skip_start > skip_end)
386         usage();
387       skip = TRUE;
388 
389     } else if (keymatch(arg, "crop", 2)) {
390       char c;
391       if (++argn >= argc)
392         usage();
393       if (sscanf(argv[argn], "%u%c%u+%u+%u", &crop_width, &c, &crop_height,
394                  &crop_x, &crop_y) != 5 ||
395           (c != 'X' && c != 'x') || crop_width < 1 || crop_height < 1)
396         usage();
397       crop = TRUE;
398 
399     } else if (keymatch(arg, "targa", 1)) {
400       /* Targa output format. */
401       requested_fmt = FMT_TARGA;
402 
403     } else {
404       usage();                  /* bogus switch */
405     }
406   }
407 
408   return argn;                  /* return index of next arg (file name) */
409 }
410 
411 
412 /*
413  * Marker processor for COM and interesting APPn markers.
414  * This replaces the library's built-in processor, which just skips the marker.
415  * We want to print out the marker as text, to the extent possible.
416  * Note this code relies on a non-suspending data source.
417  */
418 
419 LOCAL(unsigned int)
jpeg_getc(j_decompress_ptr cinfo)420 jpeg_getc (j_decompress_ptr cinfo)
421 /* Read next byte */
422 {
423   struct jpeg_source_mgr * datasrc = cinfo->src;
424 
425   if (datasrc->bytes_in_buffer == 0) {
426     if (! (*datasrc->fill_input_buffer) (cinfo))
427       ERREXIT(cinfo, JERR_CANT_SUSPEND);
428   }
429   datasrc->bytes_in_buffer--;
430   return GETJOCTET(*datasrc->next_input_byte++);
431 }
432 
433 
434 METHODDEF(boolean)
print_text_marker(j_decompress_ptr cinfo)435 print_text_marker (j_decompress_ptr cinfo)
436 {
437   boolean traceit = (cinfo->err->trace_level >= 1);
438   INT32 length;
439   unsigned int ch;
440   unsigned int lastch = 0;
441 
442   length = jpeg_getc(cinfo) << 8;
443   length += jpeg_getc(cinfo);
444   length -= 2;                  /* discount the length word itself */
445 
446   if (traceit) {
447     if (cinfo->unread_marker == JPEG_COM)
448       fprintf(stderr, "Comment, length %ld:\n", (long) length);
449     else                        /* assume it is an APPn otherwise */
450       fprintf(stderr, "APP%d, length %ld:\n",
451               cinfo->unread_marker - JPEG_APP0, (long) length);
452   }
453 
454   while (--length >= 0) {
455     ch = jpeg_getc(cinfo);
456     if (traceit) {
457       /* Emit the character in a readable form.
458        * Nonprintables are converted to \nnn form,
459        * while \ is converted to \\.
460        * Newlines in CR, CR/LF, or LF form will be printed as one newline.
461        */
462       if (ch == '\r') {
463         fprintf(stderr, "\n");
464       } else if (ch == '\n') {
465         if (lastch != '\r')
466           fprintf(stderr, "\n");
467       } else if (ch == '\\') {
468         fprintf(stderr, "\\\\");
469       } else if (isprint(ch)) {
470         putc(ch, stderr);
471       } else {
472         fprintf(stderr, "\\%03o", ch);
473       }
474       lastch = ch;
475     }
476   }
477 
478   if (traceit)
479     fprintf(stderr, "\n");
480 
481   return TRUE;
482 }
483 
484 
485 /*
486  * The main program.
487  */
488 
489 int
main(int argc,char ** argv)490 main (int argc, char **argv)
491 {
492   struct jpeg_decompress_struct cinfo;
493   struct jpeg_error_mgr jerr;
494 #ifdef PROGRESS_REPORT
495   struct cdjpeg_progress_mgr progress;
496 #endif
497   int file_index;
498   djpeg_dest_ptr dest_mgr = NULL;
499   FILE * input_file;
500   FILE * output_file;
501   unsigned char *inbuffer = NULL;
502   unsigned long insize = 0;
503   JDIMENSION num_scanlines;
504 
505   /* On Mac, fetch a command line. */
506 #ifdef USE_CCOMMAND
507   argc = ccommand(&argv);
508 #endif
509 
510   progname = argv[0];
511   if (progname == NULL || progname[0] == 0)
512     progname = "djpeg";         /* in case C library doesn't provide it */
513 
514   /* Initialize the JPEG decompression object with default error handling. */
515   cinfo.err = jpeg_std_error(&jerr);
516   jpeg_create_decompress(&cinfo);
517   /* Add some application-specific error messages (from cderror.h) */
518   jerr.addon_message_table = cdjpeg_message_table;
519   jerr.first_addon_message = JMSG_FIRSTADDONCODE;
520   jerr.last_addon_message = JMSG_LASTADDONCODE;
521 
522   /* Insert custom marker processor for COM and APP12.
523    * APP12 is used by some digital camera makers for textual info,
524    * so we provide the ability to display it as text.
525    * If you like, additional APPn marker types can be selected for display,
526    * but don't try to override APP0 or APP14 this way (see libjpeg.txt).
527    */
528   jpeg_set_marker_processor(&cinfo, JPEG_COM, print_text_marker);
529   jpeg_set_marker_processor(&cinfo, JPEG_APP0+12, print_text_marker);
530 
531   /* Scan command line to find file names. */
532   /* It is convenient to use just one switch-parsing routine, but the switch
533    * values read here are ignored; we will rescan the switches after opening
534    * the input file.
535    * (Exception: tracing level set here controls verbosity for COM markers
536    * found during jpeg_read_header...)
537    */
538 
539   file_index = parse_switches(&cinfo, argc, argv, 0, FALSE);
540 
541 #ifdef TWO_FILE_COMMANDLINE
542   /* Must have either -outfile switch or explicit output file name */
543   if (outfilename == NULL) {
544     if (file_index != argc-2) {
545       fprintf(stderr, "%s: must name one input and one output file\n",
546               progname);
547       usage();
548     }
549     outfilename = argv[file_index+1];
550   } else {
551     if (file_index != argc-1) {
552       fprintf(stderr, "%s: must name one input and one output file\n",
553               progname);
554       usage();
555     }
556   }
557 #else
558   /* Unix style: expect zero or one file name */
559   if (file_index < argc-1) {
560     fprintf(stderr, "%s: only one input file\n", progname);
561     usage();
562   }
563 #endif /* TWO_FILE_COMMANDLINE */
564 
565   /* Open the input file. */
566   if (file_index < argc) {
567     if ((input_file = fopen(argv[file_index], READ_BINARY)) == NULL) {
568       fprintf(stderr, "%s: can't open %s\n", progname, argv[file_index]);
569       exit(EXIT_FAILURE);
570     }
571   } else {
572     /* default input file is stdin */
573     input_file = read_stdin();
574   }
575 
576   /* Open the output file. */
577   if (outfilename != NULL) {
578     if ((output_file = fopen(outfilename, WRITE_BINARY)) == NULL) {
579       fprintf(stderr, "%s: can't open %s\n", progname, outfilename);
580       exit(EXIT_FAILURE);
581     }
582   } else {
583     /* default output file is stdout */
584     output_file = write_stdout();
585   }
586 
587 #ifdef PROGRESS_REPORT
588   start_progress_monitor((j_common_ptr) &cinfo, &progress);
589 #endif
590 
591   /* Specify data source for decompression */
592 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
593   if (memsrc) {
594     size_t nbytes;
595     do {
596       inbuffer = (unsigned char *)realloc(inbuffer, insize + INPUT_BUF_SIZE);
597       if (inbuffer == NULL) {
598         fprintf(stderr, "%s: memory allocation failure\n", progname);
599         exit(EXIT_FAILURE);
600       }
601       nbytes = JFREAD(input_file, &inbuffer[insize], INPUT_BUF_SIZE);
602       if (nbytes < INPUT_BUF_SIZE && ferror(input_file)) {
603         if (file_index < argc)
604           fprintf(stderr, "%s: can't read from %s\n", progname,
605                   argv[file_index]);
606         else
607           fprintf(stderr, "%s: can't read from stdin\n", progname);
608       }
609       insize += (unsigned long)nbytes;
610     } while (nbytes == INPUT_BUF_SIZE);
611     fprintf(stderr, "Compressed size:  %lu bytes\n", insize);
612     jpeg_mem_src(&cinfo, inbuffer, insize);
613   } else
614 #endif
615     jpeg_stdio_src(&cinfo, input_file);
616 
617   /* Read file header, set default decompression parameters */
618   (void) jpeg_read_header(&cinfo, TRUE);
619 
620   /* Adjust default decompression parameters by re-parsing the options */
621   file_index = parse_switches(&cinfo, argc, argv, 0, TRUE);
622 
623   /* Initialize the output module now to let it override any crucial
624    * option settings (for instance, GIF wants to force color quantization).
625    */
626   switch (requested_fmt) {
627 #ifdef BMP_SUPPORTED
628   case FMT_BMP:
629     dest_mgr = jinit_write_bmp(&cinfo, FALSE);
630     break;
631   case FMT_OS2:
632     dest_mgr = jinit_write_bmp(&cinfo, TRUE);
633     break;
634 #endif
635 #ifdef GIF_SUPPORTED
636   case FMT_GIF:
637     dest_mgr = jinit_write_gif(&cinfo);
638     break;
639 #endif
640 #ifdef PPM_SUPPORTED
641   case FMT_PPM:
642     dest_mgr = jinit_write_ppm(&cinfo);
643     break;
644 #endif
645 #ifdef RLE_SUPPORTED
646   case FMT_RLE:
647     dest_mgr = jinit_write_rle(&cinfo);
648     break;
649 #endif
650 #ifdef TARGA_SUPPORTED
651   case FMT_TARGA:
652     dest_mgr = jinit_write_targa(&cinfo);
653     break;
654 #endif
655   default:
656     ERREXIT(&cinfo, JERR_UNSUPPORTED_FORMAT);
657     break;
658   }
659   dest_mgr->output_file = output_file;
660 
661   /* Start decompressor */
662   (void) jpeg_start_decompress(&cinfo);
663 
664   /* Skip rows */
665   if (skip) {
666     JDIMENSION tmp;
667 
668     /* Check for valid skip_end.  We cannot check this value until after
669      * jpeg_start_decompress() is called.  Note that we have already verified
670      * that skip_start <= skip_end.
671      */
672     if (skip_end > cinfo.output_height - 1) {
673       fprintf(stderr, "%s: skip region exceeds image height %d\n", progname,
674               cinfo.output_height);
675       exit(EXIT_FAILURE);
676     }
677 
678     /* Write output file header.  This is a hack to ensure that the destination
679      * manager creates an output image of the proper size.
680      */
681     tmp = cinfo.output_height;
682     cinfo.output_height -= (skip_end - skip_start + 1);
683     (*dest_mgr->start_output) (&cinfo, dest_mgr);
684     cinfo.output_height = tmp;
685 
686     /* Process data */
687     while (cinfo.output_scanline < skip_start) {
688       num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
689                                           dest_mgr->buffer_height);
690       (*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
691     }
692     jpeg_skip_scanlines(&cinfo, skip_end - skip_start + 1);
693     while (cinfo.output_scanline < cinfo.output_height) {
694       num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
695                                           dest_mgr->buffer_height);
696       (*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
697     }
698 
699   /* Decompress a subregion */
700   } else if (crop) {
701     JDIMENSION tmp;
702 
703     /* Check for valid crop dimensions.  We cannot check these values until
704      * after jpeg_start_decompress() is called.
705      */
706     if (crop_x + crop_width > cinfo.output_width ||
707         crop_y + crop_height > cinfo.output_height) {
708       fprintf(stderr, "%s: crop dimensions exceed image dimensions %d x %d\n",
709               progname, cinfo.output_width, cinfo.output_height);
710       exit(EXIT_FAILURE);
711     }
712 
713     jpeg_crop_scanline(&cinfo, &crop_x, &crop_width);
714     ((ppm_dest_ptr) dest_mgr)->buffer_width = cinfo.output_width *
715                                               cinfo.out_color_components *
716                                               sizeof(JSAMPLE);
717 
718     /* Write output file header.  This is a hack to ensure that the destination
719      * manager creates an output image of the proper size.
720      */
721     tmp = cinfo.output_height;
722     cinfo.output_height = crop_height;
723     (*dest_mgr->start_output) (&cinfo, dest_mgr);
724     cinfo.output_height = tmp;
725 
726     /* Process data */
727     jpeg_skip_scanlines(&cinfo, crop_y);
728     while (cinfo.output_scanline < crop_y + crop_height) {
729       num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
730                                           dest_mgr->buffer_height);
731       (*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
732     }
733     jpeg_skip_scanlines(&cinfo, cinfo.output_height - crop_y - crop_height);
734 
735   /* Normal full-image decompress */
736   } else {
737     /* Write output file header */
738     (*dest_mgr->start_output) (&cinfo, dest_mgr);
739 
740     /* Process data */
741     while (cinfo.output_scanline < cinfo.output_height) {
742       num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,
743                                           dest_mgr->buffer_height);
744       (*dest_mgr->put_pixel_rows) (&cinfo, dest_mgr, num_scanlines);
745     }
746   }
747 
748 #ifdef PROGRESS_REPORT
749   /* Hack: count final pass as done in case finish_output does an extra pass.
750    * The library won't have updated completed_passes.
751    */
752   progress.pub.completed_passes = progress.pub.total_passes;
753 #endif
754 
755   /* Finish decompression and release memory.
756    * I must do it in this order because output module has allocated memory
757    * of lifespan JPOOL_IMAGE; it needs to finish before releasing memory.
758    */
759   (*dest_mgr->finish_output) (&cinfo, dest_mgr);
760   (void) jpeg_finish_decompress(&cinfo);
761   jpeg_destroy_decompress(&cinfo);
762 
763   /* Close files, if we opened them */
764   if (input_file != stdin)
765     fclose(input_file);
766   if (output_file != stdout)
767     fclose(output_file);
768 
769 #ifdef PROGRESS_REPORT
770   end_progress_monitor((j_common_ptr) &cinfo);
771 #endif
772 
773   if (memsrc && inbuffer != NULL)
774     free(inbuffer);
775 
776   /* All done. */
777   exit(jerr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS);
778   return 0;                     /* suppress no-return-value warnings */
779 }
780