Visualization Library 2.0.0-b5

A lightweight C++ OpenGL middleware for 2D/3D graphics

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wrjpgcom.c
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1 /*
2  * wrjpgcom.c
3  *
4  * Copyright (C) 1994-1997, 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 very simple stand-alone application that inserts
9  * user-supplied text as a COM (comment) marker in a JFIF file.
10  * This may be useful as an example of the minimum logic needed to parse
11  * JPEG markers.
12  */
13 
14 #define JPEG_CJPEG_DJPEG /* to get the command-line config symbols */
15 #include "jinclude.h" /* get auto-config symbols, <stdio.h> */
16 
17 #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc() */
18 extern void * malloc ();
19 #endif
20 #include <ctype.h> /* to declare isupper(), tolower() */
21 #ifdef USE_SETMODE
22 #include <fcntl.h> /* to declare setmode()'s parameter macros */
23 /* If you have setmode() but not <io.h>, just delete this line: */
24 #include <io.h> /* to declare setmode() */
25 #endif
26 
27 #ifdef USE_CCOMMAND /* command-line reader for Macintosh */
28 #ifdef __MWERKS__
29 #include <SIOUX.h> /* Metrowerks needs this */
30 #include <console.h> /* ... and this */
31 #endif
32 #ifdef THINK_C
33 #include <console.h> /* Think declares it here */
34 #endif
35 #endif
36 
37 #ifdef DONT_USE_B_MODE /* define mode parameters for fopen() */
38 #define READ_BINARY "r"
39 #define WRITE_BINARY "w"
40 #else
41 #ifdef VMS /* VMS is very nonstandard */
42 #define READ_BINARY "rb", "ctx=stm"
43 #define WRITE_BINARY "wb", "ctx=stm"
44 #else /* standard ANSI-compliant case */
45 #define READ_BINARY "rb"
46 #define WRITE_BINARY "wb"
47 #endif
48 #endif
49 
50 #ifndef EXIT_FAILURE /* define exit() codes if not provided */
51 #define EXIT_FAILURE 1
52 #endif
53 #ifndef EXIT_SUCCESS
54 #ifdef VMS
55 #define EXIT_SUCCESS 1 /* VMS is very nonstandard */
56 #else
57 #define EXIT_SUCCESS 0
58 #endif
59 #endif
60 
61 /* Reduce this value if your malloc() can't allocate blocks up to 64K.
62  * On DOS, compiling in large model is usually a better solution.
63  */
64 
65 #ifndef MAX_COM_LENGTH
66 #define MAX_COM_LENGTH 65000L /* must be <= 65533 in any case */
67 #endif
68 
69 
70 /*
71  * These macros are used to read the input file and write the output file.
72  * To reuse this code in another application, you might need to change these.
73  */
74 
75 static FILE * infile; /* input JPEG file */
76 
77 /* Return next input byte, or EOF if no more */
78 #define NEXTBYTE() getc(infile)
79 
80 static FILE * outfile; /* output JPEG file */
81 
82 /* Emit an output byte */
83 #define PUTBYTE(x) putc((x), outfile)
84 
85 
86 /* Error exit handler */
87 #define ERREXIT(msg) (fprintf(stderr, "%s\n", msg), exit(EXIT_FAILURE))
88 
89 
90 /* Read one byte, testing for EOF */
91 static int
92 read_1_byte (void)
93 {
94  int c;
95 
96  c = NEXTBYTE();
97  if (c == EOF)
98  ERREXIT("Premature EOF in JPEG file");
99  return c;
100 }
101 
102 /* Read 2 bytes, convert to unsigned int */
103 /* All 2-byte quantities in JPEG markers are MSB first */
104 static unsigned int
105 read_2_bytes (void)
106 {
107  int c1, c2;
108 
109  c1 = NEXTBYTE();
110  if (c1 == EOF)
111  ERREXIT("Premature EOF in JPEG file");
112  c2 = NEXTBYTE();
113  if (c2 == EOF)
114  ERREXIT("Premature EOF in JPEG file");
115  return (((unsigned int) c1) << 8) + ((unsigned int) c2);
116 }
117 
118 
119 /* Routines to write data to output file */
120 
121 static void
122 write_1_byte (int c)
123 {
124  PUTBYTE(c);
125 }
126 
127 static void
128 write_2_bytes (unsigned int val)
129 {
130  PUTBYTE((val >> 8) & 0xFF);
131  PUTBYTE(val & 0xFF);
132 }
133 
134 static void
135 write_marker (int marker)
136 {
137  PUTBYTE(0xFF);
138  PUTBYTE(marker);
139 }
140 
141 static void
142 copy_rest_of_file (void)
143 {
144  int c;
145 
146  while ((c = NEXTBYTE()) != EOF)
147  PUTBYTE(c);
148 }
149 
150 
151 /*
152  * JPEG markers consist of one or more 0xFF bytes, followed by a marker
153  * code byte (which is not an FF). Here are the marker codes of interest
154  * in this program. (See jdmarker.c for a more complete list.)
155  */
156 
157 #define M_SOF0 0xC0 /* Start Of Frame N */
158 #define M_SOF1 0xC1 /* N indicates which compression process */
159 #define M_SOF2 0xC2 /* Only SOF0-SOF2 are now in common use */
160 #define M_SOF3 0xC3
161 #define M_SOF5 0xC5 /* NB: codes C4 and CC are NOT SOF markers */
162 #define M_SOF6 0xC6
163 #define M_SOF7 0xC7
164 #define M_SOF9 0xC9
165 #define M_SOF10 0xCA
166 #define M_SOF11 0xCB
167 #define M_SOF13 0xCD
168 #define M_SOF14 0xCE
169 #define M_SOF15 0xCF
170 #define M_SOI 0xD8 /* Start Of Image (beginning of datastream) */
171 #define M_EOI 0xD9 /* End Of Image (end of datastream) */
172 #define M_SOS 0xDA /* Start Of Scan (begins compressed data) */
173 #define M_COM 0xFE /* COMment */
174 
175 
176 /*
177  * Find the next JPEG marker and return its marker code.
178  * We expect at least one FF byte, possibly more if the compressor used FFs
179  * to pad the file. (Padding FFs will NOT be replicated in the output file.)
180  * There could also be non-FF garbage between markers. The treatment of such
181  * garbage is unspecified; we choose to skip over it but emit a warning msg.
182  * NB: this routine must not be used after seeing SOS marker, since it will
183  * not deal correctly with FF/00 sequences in the compressed image data...
184  */
185 
186 static int
187 next_marker (void)
188 {
189  int c;
190  int discarded_bytes = 0;
191 
192  /* Find 0xFF byte; count and skip any non-FFs. */
193  c = read_1_byte();
194  while (c != 0xFF) {
195  discarded_bytes++;
196  c = read_1_byte();
197  }
198  /* Get marker code byte, swallowing any duplicate FF bytes. Extra FFs
199  * are legal as pad bytes, so don't count them in discarded_bytes.
200  */
201  do {
202  c = read_1_byte();
203  } while (c == 0xFF);
204 
205  if (discarded_bytes != 0) {
206  fprintf(stderr, "Warning: garbage data found in JPEG file\n");
207  }
208 
209  return c;
210 }
211 
212 
213 /*
214  * Read the initial marker, which should be SOI.
215  * For a JFIF file, the first two bytes of the file should be literally
216  * 0xFF M_SOI. To be more general, we could use next_marker, but if the
217  * input file weren't actually JPEG at all, next_marker might read the whole
218  * file and then return a misleading error message...
219  */
220 
221 static int
222 first_marker (void)
223 {
224  int c1, c2;
225 
226  c1 = NEXTBYTE();
227  c2 = NEXTBYTE();
228  if (c1 != 0xFF || c2 != M_SOI)
229  ERREXIT("Not a JPEG file");
230  return c2;
231 }
232 
233 
234 /*
235  * Most types of marker are followed by a variable-length parameter segment.
236  * This routine skips over the parameters for any marker we don't otherwise
237  * want to process.
238  * Note that we MUST skip the parameter segment explicitly in order not to
239  * be fooled by 0xFF bytes that might appear within the parameter segment;
240  * such bytes do NOT introduce new markers.
241  */
242 
243 static void
244 copy_variable (void)
245 /* Copy an unknown or uninteresting variable-length marker */
246 {
247  unsigned int length;
248 
249  /* Get the marker parameter length count */
250  length = read_2_bytes();
251  write_2_bytes(length);
252  /* Length includes itself, so must be at least 2 */
253  if (length < 2)
254  ERREXIT("Erroneous JPEG marker length");
255  length -= 2;
256  /* Skip over the remaining bytes */
257  while (length > 0) {
258  write_1_byte(read_1_byte());
259  length--;
260  }
261 }
262 
263 static void
264 skip_variable (void)
265 /* Skip over an unknown or uninteresting variable-length marker */
266 {
267  unsigned int length;
268 
269  /* Get the marker parameter length count */
270  length = read_2_bytes();
271  /* Length includes itself, so must be at least 2 */
272  if (length < 2)
273  ERREXIT("Erroneous JPEG marker length");
274  length -= 2;
275  /* Skip over the remaining bytes */
276  while (length > 0) {
277  (void) read_1_byte();
278  length--;
279  }
280 }
281 
282 
283 /*
284  * Parse the marker stream until SOFn or EOI is seen;
285  * copy data to output, but discard COM markers unless keep_COM is true.
286  */
287 
288 static int
289 scan_JPEG_header (int keep_COM)
290 {
291  int marker;
292 
293  /* Expect SOI at start of file */
294  if (first_marker() != M_SOI)
295  ERREXIT("Expected SOI marker first");
296  write_marker(M_SOI);
297 
298  /* Scan miscellaneous markers until we reach SOFn. */
299  for (;;) {
300  marker = next_marker();
301  switch (marker) {
302  /* Note that marker codes 0xC4, 0xC8, 0xCC are not, and must not be,
303  * treated as SOFn. C4 in particular is actually DHT.
304  */
305  case M_SOF0: /* Baseline */
306  case M_SOF1: /* Extended sequential, Huffman */
307  case M_SOF2: /* Progressive, Huffman */
308  case M_SOF3: /* Lossless, Huffman */
309  case M_SOF5: /* Differential sequential, Huffman */
310  case M_SOF6: /* Differential progressive, Huffman */
311  case M_SOF7: /* Differential lossless, Huffman */
312  case M_SOF9: /* Extended sequential, arithmetic */
313  case M_SOF10: /* Progressive, arithmetic */
314  case M_SOF11: /* Lossless, arithmetic */
315  case M_SOF13: /* Differential sequential, arithmetic */
316  case M_SOF14: /* Differential progressive, arithmetic */
317  case M_SOF15: /* Differential lossless, arithmetic */
318  return marker;
319 
320  case M_SOS: /* should not see compressed data before SOF */
321  ERREXIT("SOS without prior SOFn");
322  break;
323 
324  case M_EOI: /* in case it's a tables-only JPEG stream */
325  return marker;
326 
327  case M_COM: /* Existing COM: conditionally discard */
328  if (keep_COM) {
329  write_marker(marker);
330  copy_variable();
331  } else {
332  skip_variable();
333  }
334  break;
335 
336  default: /* Anything else just gets copied */
337  write_marker(marker);
338  copy_variable(); /* we assume it has a parameter count... */
339  break;
340  }
341  } /* end loop */
342 }
343 
344 
345 /* Command line parsing code */
346 
347 static const char * progname; /* program name for error messages */
348 
349 
350 static void
351 usage (void)
352 /* complain about bad command line */
353 {
354  fprintf(stderr, "wrjpgcom inserts a textual comment in a JPEG file.\n");
355  fprintf(stderr, "You can add to or replace any existing comment(s).\n");
356 
357  fprintf(stderr, "Usage: %s [switches] ", progname);
358 #ifdef TWO_FILE_COMMANDLINE
359  fprintf(stderr, "inputfile outputfile\n");
360 #else
361  fprintf(stderr, "[inputfile]\n");
362 #endif
363 
364  fprintf(stderr, "Switches (names may be abbreviated):\n");
365  fprintf(stderr, " -replace Delete any existing comments\n");
366  fprintf(stderr, " -comment \"text\" Insert comment with given text\n");
367  fprintf(stderr, " -cfile name Read comment from named file\n");
368  fprintf(stderr, "Notice that you must put quotes around the comment text\n");
369  fprintf(stderr, "when you use -comment.\n");
370  fprintf(stderr, "If you do not give either -comment or -cfile on the command line,\n");
371  fprintf(stderr, "then the comment text is read from standard input.\n");
372  fprintf(stderr, "It can be multiple lines, up to %u characters total.\n",
373  (unsigned int) MAX_COM_LENGTH);
374 #ifndef TWO_FILE_COMMANDLINE
375  fprintf(stderr, "You must specify an input JPEG file name when supplying\n");
376  fprintf(stderr, "comment text from standard input.\n");
377 #endif
378 
379  exit(EXIT_FAILURE);
380 }
381 
382 
383 static int
384 keymatch (char * arg, const char * keyword, int minchars)
385 /* Case-insensitive matching of (possibly abbreviated) keyword switches. */
386 /* keyword is the constant keyword (must be lower case already), */
387 /* minchars is length of minimum legal abbreviation. */
388 {
389  register int ca, ck;
390  register int nmatched = 0;
391 
392  while ((ca = *arg++) != '\0') {
393  if ((ck = *keyword++) == '\0')
394  return 0; /* arg longer than keyword, no good */
395  if (isupper(ca)) /* force arg to lcase (assume ck is already) */
396  ca = tolower(ca);
397  if (ca != ck)
398  return 0; /* no good */
399  nmatched++; /* count matched characters */
400  }
401  /* reached end of argument; fail if it's too short for unique abbrev */
402  if (nmatched < minchars)
403  return 0;
404  return 1; /* A-OK */
405 }
406 
407 
408 /*
409  * The main program.
410  */
411 
412 int
413 main (int argc, char **argv)
414 {
415  int argn;
416  char * arg;
417  int keep_COM = 1;
418  char * comment_arg = NULL;
419  FILE * comment_file = NULL;
420  unsigned int comment_length = 0;
421  int marker;
422 
423  /* On Mac, fetch a command line. */
424 #ifdef USE_CCOMMAND
425  argc = ccommand(&argv);
426 #endif
427 
428  progname = argv[0];
429  if (progname == NULL || progname[0] == 0)
430  progname = "wrjpgcom"; /* in case C library doesn't provide it */
431 
432  /* Parse switches, if any */
433  for (argn = 1; argn < argc; argn++) {
434  arg = argv[argn];
435  if (arg[0] != '-')
436  break; /* not switch, must be file name */
437  arg++; /* advance over '-' */
438  if (keymatch(arg, "replace", 1)) {
439  keep_COM = 0;
440  } else if (keymatch(arg, "cfile", 2)) {
441  if (++argn >= argc) usage();
442  if ((comment_file = fopen(argv[argn], "r")) == NULL) {
443  fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]);
444  exit(EXIT_FAILURE);
445  }
446  } else if (keymatch(arg, "comment", 1)) {
447  if (++argn >= argc) usage();
448  comment_arg = argv[argn];
449  /* If the comment text starts with '"', then we are probably running
450  * under MS-DOG and must parse out the quoted string ourselves. Sigh.
451  */
452  if (comment_arg[0] == '"') {
453  comment_arg = (char *) malloc((size_t) MAX_COM_LENGTH);
454  if (comment_arg == NULL)
455  ERREXIT("Insufficient memory");
456  strcpy(comment_arg, argv[argn]+1);
457  for (;;) {
458  comment_length = (unsigned int) strlen(comment_arg);
459  if (comment_length > 0 && comment_arg[comment_length-1] == '"') {
460  comment_arg[comment_length-1] = '\0'; /* zap terminating quote */
461  break;
462  }
463  if (++argn >= argc)
464  ERREXIT("Missing ending quote mark");
465  strcat(comment_arg, " ");
466  strcat(comment_arg, argv[argn]);
467  }
468  }
469  comment_length = (unsigned int) strlen(comment_arg);
470  } else
471  usage();
472  }
473 
474  /* Cannot use both -comment and -cfile. */
475  if (comment_arg != NULL && comment_file != NULL)
476  usage();
477  /* If there is neither -comment nor -cfile, we will read the comment text
478  * from stdin; in this case there MUST be an input JPEG file name.
479  */
480  if (comment_arg == NULL && comment_file == NULL && argn >= argc)
481  usage();
482 
483  /* Open the input file. */
484  if (argn < argc) {
485  if ((infile = fopen(argv[argn], READ_BINARY)) == NULL) {
486  fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]);
487  exit(EXIT_FAILURE);
488  }
489  } else {
490  /* default input file is stdin */
491 #ifdef USE_SETMODE /* need to hack file mode? */
492  setmode(fileno(stdin), O_BINARY);
493 #endif
494 #ifdef USE_FDOPEN /* need to re-open in binary mode? */
495  if ((infile = fdopen(fileno(stdin), READ_BINARY)) == NULL) {
496  fprintf(stderr, "%s: can't open stdin\n", progname);
497  exit(EXIT_FAILURE);
498  }
499 #else
500  infile = stdin;
501 #endif
502  }
503 
504  /* Open the output file. */
505 #ifdef TWO_FILE_COMMANDLINE
506  /* Must have explicit output file name */
507  if (argn != argc-2) {
508  fprintf(stderr, "%s: must name one input and one output file\n",
509  progname);
510  usage();
511  }
512  if ((outfile = fopen(argv[argn+1], WRITE_BINARY)) == NULL) {
513  fprintf(stderr, "%s: can't open %s\n", progname, argv[argn+1]);
514  exit(EXIT_FAILURE);
515  }
516 #else
517  /* Unix style: expect zero or one file name */
518  if (argn < argc-1) {
519  fprintf(stderr, "%s: only one input file\n", progname);
520  usage();
521  }
522  /* default output file is stdout */
523 #ifdef USE_SETMODE /* need to hack file mode? */
524  setmode(fileno(stdout), O_BINARY);
525 #endif
526 #ifdef USE_FDOPEN /* need to re-open in binary mode? */
527  if ((outfile = fdopen(fileno(stdout), WRITE_BINARY)) == NULL) {
528  fprintf(stderr, "%s: can't open stdout\n", progname);
529  exit(EXIT_FAILURE);
530  }
531 #else
532  outfile = stdout;
533 #endif
534 #endif /* TWO_FILE_COMMANDLINE */
535 
536  /* Collect comment text from comment_file or stdin, if necessary */
537  if (comment_arg == NULL) {
538  FILE * src_file;
539  int c;
540 
541  comment_arg = (char *) malloc((size_t) MAX_COM_LENGTH);
542  if (comment_arg == NULL)
543  ERREXIT("Insufficient memory");
544  comment_length = 0;
545  src_file = (comment_file != NULL ? comment_file : stdin);
546  while ((c = getc(src_file)) != EOF) {
547  if (comment_length >= (unsigned int) MAX_COM_LENGTH) {
548  fprintf(stderr, "Comment text may not exceed %u bytes\n",
549  (unsigned int) MAX_COM_LENGTH);
550  exit(EXIT_FAILURE);
551  }
552  comment_arg[comment_length++] = (char) c;
553  }
554  if (comment_file != NULL)
555  fclose(comment_file);
556  }
557 
558  /* Copy JPEG headers until SOFn marker;
559  * we will insert the new comment marker just before SOFn.
560  * This (a) causes the new comment to appear after, rather than before,
561  * existing comments; and (b) ensures that comments come after any JFIF
562  * or JFXX markers, as required by the JFIF specification.
563  */
564  marker = scan_JPEG_header(keep_COM);
565  /* Insert the new COM marker, but only if nonempty text has been supplied */
566  if (comment_length > 0) {
567  write_marker(M_COM);
568  write_2_bytes(comment_length + 2);
569  while (comment_length > 0) {
570  write_1_byte(*comment_arg++);
571  comment_length--;
572  }
573  }
574  /* Duplicate the remainder of the source file.
575  * Note that any COM markers occuring after SOF will not be touched.
576  */
577  write_marker(marker);
578  copy_rest_of_file();
579 
580  /* All done. */
581  exit(EXIT_SUCCESS);
582  return 0; /* suppress no-return-value warnings */
583 }
GLenum GLuint GLenum GLsizei length
const char * keyword
Definition: cdjpeg.h:149
#define M_SOF5
Definition: wrjpgcom.c:161
#define NULL
Definition: ftobjs.h:61
#define M_SOF6
Definition: wrjpgcom.c:162
#define M_SOF9
Definition: wrjpgcom.c:164
first_marker(j_decompress_ptr cinfo)
Definition: jdmarker.c:921
#define M_EOI
Definition: wrjpgcom.c:171
#define ERREXIT(msg)
Definition: wrjpgcom.c:87
char * malloc()
#define EXIT_SUCCESS
Definition: wrjpgcom.c:57
typedef void(APIENTRY *GLDEBUGPROCARB)(GLenum source
#define EXIT_FAILURE
Definition: wrjpgcom.c:51
#define NEXTBYTE()
Definition: wrjpgcom.c:78
skip_variable(j_decompress_ptr cinfo)
Definition: jdmarker.c:845
#define MAX_COM_LENGTH
Definition: wrjpgcom.c:66
#define M_SOF3
Definition: wrjpgcom.c:160
#define READ_BINARY
Definition: wrjpgcom.c:45
GLsizeiptr const GLvoid GLenum usage
int marker
Definition: jpeglib.h:950
FILE * outfile
Definition: jpeglib.h:910
keymatch(char *arg, const char *keyword, int minchars)
Definition: cdjpeg.c:122
const char int minchars
Definition: cdjpeg.h:149
#define M_SOF7
Definition: wrjpgcom.c:163
int main(int argc, char **argv)
Definition: wrjpgcom.c:413
GLuint GLfloat * val
#define M_SOF13
Definition: wrjpgcom.c:167
#define M_SOF10
Definition: wrjpgcom.c:165
const GLubyte * c
#define EOF
Definition: afmparse.c:58
#define WRITE_BINARY
Definition: wrjpgcom.c:46
typedef int
Definition: png.h:978
FILE * infile
Definition: cdjpeg.h:141
#define M_SOF14
Definition: wrjpgcom.c:168
#define M_SOF15
Definition: wrjpgcom.c:169
#define M_SOF11
Definition: wrjpgcom.c:166
char * arg
Definition: cdjpeg.h:136
#define M_SOF2
Definition: wrjpgcom.c:159
#define PUTBYTE(x)
Definition: wrjpgcom.c:83
#define M_SOF1
Definition: wrjpgcom.c:158
#define M_SOS
Definition: wrjpgcom.c:172
#define M_SOF0
Definition: wrjpgcom.c:157
next_marker(j_decompress_ptr cinfo)
Definition: jdmarker.c:874
#define M_COM
Definition: wrjpgcom.c:173
#define M_SOI
Definition: wrjpgcom.c:170