summaryrefslogtreecommitdiff
path: root/Build/source/libs/libpng/libpng-src/contrib/pngminus/pnm2png.c
blob: 052fd3272c862b5dd424db6b5012da8119725d22 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
/*
 *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
 *  copyright (C) 1999-2019 by Willem van Schaik <willem at schaik dot com>
 *
 *  This software is released under the MIT license. For conditions of
 *  distribution and use, see the LICENSE file part of this package.
 */

#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>

#ifndef BOOL
#define BOOL unsigned char
#endif
#ifndef TRUE
#define TRUE ((BOOL) 1)
#endif
#ifndef FALSE
#define FALSE ((BOOL) 0)
#endif

#include "png.h"

/* function prototypes */

int main (int argc, char *argv[]);
void usage ();
BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
              BOOL interlace, BOOL alpha);
BOOL do_pnm2png (png_struct *png_ptr, png_info *info_ptr,
                 FILE *pnm_file, FILE *alpha_file,
                 BOOL interlace, BOOL alpha);
int fscan_pnm_magic (FILE *pnm_file, char *magic_buf, size_t magic_buf_size);
int fscan_pnm_token (FILE *pnm_file, char *token_buf, size_t token_buf_size);
int fscan_pnm_uint_32 (FILE *pnm_file, png_uint_32 *num_ptr);
png_uint_32 get_pnm_data (FILE *pnm_file, int depth);
png_uint_32 get_pnm_value (FILE *pnm_file, int depth);

/*
 *  main
 */

int main (int argc, char *argv[])
{
  FILE *fp_rd = stdin;
  FILE *fp_al = NULL;
  FILE *fp_wr = stdout;
  const char *fname_wr = NULL;
  BOOL interlace = FALSE;
  BOOL alpha = FALSE;
  int argi;
  int ret;

  for (argi = 1; argi < argc; argi++)
  {
    if (argv[argi][0] == '-')
    {
      switch (argv[argi][1])
      {
        case 'i':
          interlace = TRUE;
          break;
        case 'a':
          alpha = TRUE;
          argi++;
          if ((fp_al = fopen (argv[argi], "rb")) == NULL)
          {
            fprintf (stderr, "PNM2PNG\n");
            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n",
                     argv[argi]);
            exit (1);
          }
          break;
        case 'h':
        case '?':
          usage ();
          exit (0);
          break;
        default:
          fprintf (stderr, "PNM2PNG\n");
          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
          usage ();
          exit (1);
          break;
      } /* end switch */
    }
    else if (fp_rd == stdin)
    {
      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
      {
        fprintf (stderr, "PNM2PNG\n");
        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
        exit (1);
      }
    }
    else if (fp_wr == stdout)
    {
      fname_wr = argv[argi];
      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
      {
        fprintf (stderr, "PNM2PNG\n");
        fprintf (stderr, "Error:  cannot create PNG-file %s\n", argv[argi]);
        exit (1);
      }
    }
    else
    {
      fprintf (stderr, "PNM2PNG\n");
      fprintf (stderr, "Error:  too many parameters\n");
      usage ();
      exit (1);
    }
  } /* end for */

#if defined(O_BINARY) && (O_BINARY != 0)
  /* set stdin/stdout to binary,
   * we're reading the PNM always! in binary format
   */
  if (fp_rd == stdin)
    setmode (fileno (stdin), O_BINARY);
  if (fp_wr == stdout)
    setmode (fileno (stdout), O_BINARY);
#endif

  /* call the conversion program itself */
  ret = pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha);

  /* close input file */
  fclose (fp_rd);
  /* close output file */
  fclose (fp_wr);
  /* close alpha file */
  if (alpha)
    fclose (fp_al);

  if (!ret)
  {
    fprintf (stderr, "PNM2PNG\n");
    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
    if (fname_wr)
      remove (fname_wr); /* no broken output file shall remain behind */
    exit (1);
  }

  return 0;
}

/*
 *  usage
 */

void usage ()
{
  fprintf (stderr, "PNM2PNG\n");
  fprintf (stderr, "   by Willem van Schaik, 1999\n");
  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");
  fprintf (stderr, "   or:  ... | pnm2png [options]\n");
  fprintf (stderr, "Options:\n");
  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");
  fprintf (stderr,
      "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
  fprintf (stderr, "   -h | -?  print this help-information\n");
}

/*
 *  pnm2png
 */

BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
              BOOL interlace, BOOL alpha)
{
  png_struct    *png_ptr;
  png_info      *info_ptr;
  BOOL          ret;

  /* initialize the libpng context for writing to png_file */

  png_ptr = png_create_write_struct (png_get_libpng_ver(NULL),
                                     NULL, NULL, NULL);
  if (!png_ptr)
    return FALSE; /* out of memory */

  info_ptr = png_create_info_struct (png_ptr);
  if (!info_ptr)
  {
    png_destroy_write_struct (&png_ptr, NULL);
    return FALSE; /* out of memory */
  }

  if (setjmp (png_jmpbuf (png_ptr)))
  {
    png_destroy_write_struct (&png_ptr, &info_ptr);
    return FALSE; /* generic libpng error */
  }

  png_init_io (png_ptr, png_file);

  /* do the actual conversion */
  ret = do_pnm2png (png_ptr, info_ptr, pnm_file, alpha_file, interlace, alpha);

  /* clean up the libpng structures and their internally-managed data */
  png_destroy_write_struct (&png_ptr, &info_ptr);

  return ret;
}

/*
 *  do_pnm2png - does the conversion in a fully-initialized libpng context
 */

BOOL do_pnm2png (png_struct *png_ptr, png_info *info_ptr,
                 FILE *pnm_file, FILE *alpha_file,
                 BOOL interlace, BOOL alpha)
{
  png_byte      **row_pointers;
  png_byte      *pix_ptr;
  int           bit_depth;
  int           color_type;
  int           channels;
  char          magic_token[4];
  BOOL          raw;
  png_uint_32   width, height, maxval;
  png_uint_32   row_bytes;
  png_uint_32   row, col;
  png_uint_32   val16, i;
  png_uint_32   alpha_width = 0, alpha_height = 0;
  int           alpha_depth = 0, alpha_present = 0;
  BOOL          alpha_raw = FALSE;
  BOOL          packed_bitmap = FALSE;

  /* read header of PNM file */

  if (fscan_pnm_magic (pnm_file, magic_token, sizeof (magic_token)) != 1)
    return FALSE; /* not a PNM file */

  if ((magic_token[1] == '1') || (magic_token[1] == '4'))
  {
    if ((fscan_pnm_uint_32 (pnm_file, &width) != 1) ||
        (fscan_pnm_uint_32 (pnm_file, &height) != 1))
      return FALSE; /* bad PBM file header */
  } else if ((magic_token[1] == '2') || (magic_token[1] == '5') ||
             (magic_token[1] == '3') || (magic_token[1] == '6'))
  {
    if ((fscan_pnm_uint_32 (pnm_file, &width) != 1) ||
        (fscan_pnm_uint_32 (pnm_file, &height) != 1) ||
        (fscan_pnm_uint_32 (pnm_file, &maxval) != 1))
      return FALSE; /* bad PGM/PPM file header */
  }

  if ((magic_token[1] == '1') || (magic_token[1] == '4'))
  {
    raw = (magic_token[1] == '4');
    bit_depth = 1;
    color_type = PNG_COLOR_TYPE_GRAY;
    packed_bitmap = TRUE;
  }
  else if ((magic_token[1] == '2') || (magic_token[1] == '5'))
  {
    raw = (magic_token[1] == '5');
    color_type = PNG_COLOR_TYPE_GRAY;
    if (maxval == 0)
      return FALSE;
    else if (maxval == 1)
      bit_depth = 1;
    else if (maxval <= 3)
      bit_depth = 2;
    else if (maxval <= 15)
      bit_depth = 4;
    else if (maxval <= 255)
      bit_depth = 8;
    else if (maxval <= 65535U)
      bit_depth = 16;
    else /* maxval > 65535U */
      return FALSE;
  }
  else if ((magic_token[1] == '3') || (magic_token[1] == '6'))
  {
    raw = (magic_token[1] == '6');
    color_type = PNG_COLOR_TYPE_RGB;
    if (maxval == 0)
      return FALSE;
    else if (maxval == 1)
      bit_depth = 1;
    else if (maxval <= 3)
      bit_depth = 2;
    else if (maxval <= 15)
      bit_depth = 4;
    else if (maxval <= 255)
      bit_depth = 8;
    else if (maxval <= 65535U)
      bit_depth = 16;
    else /* maxval > 65535U */
      return FALSE;
  }
  else if (magic_token[1] == '7')
  {
    fprintf (stderr, "PNM2PNG can't read PAM (P7) files\n");
    return FALSE;
  }
  else
  {
    return FALSE;
  }

  /* read header of PGM file with alpha channel */

  if (alpha)
  {
    if ((fscan_pnm_magic (alpha_file, magic_token, sizeof (magic_token)) != 1)
        || ((magic_token[1] != '2') && (magic_token[1] != '5')))
      return FALSE; /* not a PGM file */

    if ((fscan_pnm_uint_32 (alpha_file, &alpha_width) != 1) ||
        (fscan_pnm_uint_32 (alpha_file, &alpha_height) != 1) ||
        (fscan_pnm_uint_32 (alpha_file, &maxval) != 1))
      return FALSE; /* bad PGM file header */

    if ((alpha_width != width) || (alpha_height != height))
      return FALSE; /* mismatched PGM dimensions */

    alpha_raw = (magic_token[1] == '5');
    color_type |= PNG_COLOR_MASK_ALPHA;
    if (maxval == 0)
      return FALSE;
    else if (maxval == 1)
      alpha_depth = 1;
    else if (maxval <= 3)
      alpha_depth = 2;
    else if (maxval <= 15)
      alpha_depth = 4;
    else if (maxval <= 255)
      alpha_depth = 8;
    else if (maxval <= 65535U)
      alpha_depth = 16;
    else /* maxval > 65535U */
      return FALSE;
    if (alpha_depth != bit_depth)
      return FALSE;
  } /* end if alpha */

  /* calculate the number of channels and store alpha-presence */
  if (color_type == PNG_COLOR_TYPE_GRAY)
    channels = 1;
  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
    channels = 2;
  else if (color_type == PNG_COLOR_TYPE_RGB)
    channels = 3;
  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
    channels = 4;
  else
    return FALSE; /* NOTREACHED */

  alpha_present = (channels - 1) % 2;

  if (packed_bitmap)
  {
    /* row data is as many bytes as can fit width x channels x bit_depth */
    row_bytes = (width * channels * bit_depth + 7) / 8;
  }
  else
  {
    /* row_bytes is the width x number of channels x (bit-depth / 8) */
    row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
  }

  if ((row_bytes == 0) ||
      ((size_t) height > (size_t) (-1) / (size_t) row_bytes))
  {
    /* too big */
    return FALSE;
  }

  /* allocate the rows using the same memory layout as libpng, and transfer
   * their ownership to libpng, with the responsibility to clean everything up;
   * please note the use of png_calloc instead of png_malloc */
  row_pointers = (png_byte **)
                 png_calloc (png_ptr, height * sizeof (png_byte *));
  png_set_rows (png_ptr, info_ptr, row_pointers);
  png_data_freer (png_ptr, info_ptr, PNG_DESTROY_WILL_FREE_DATA, PNG_FREE_ALL);
  for (row = 0; row < height; row++)
  {
    /* the individual rows should only be allocated after all the previous
     * steps completed successfully, because libpng must handle correctly
     * any image allocation left incomplete after an out-of-memory error */
    row_pointers[row] = (png_byte *) png_malloc (png_ptr, row_bytes);
  }

  /* read the data from PNM file */

  for (row = 0; row < height; row++)
  {
    pix_ptr = row_pointers[row];
    if (packed_bitmap)
    {
      for (i = 0; i < row_bytes; i++)
      {
        /* png supports this format natively so no conversion is needed */
        *pix_ptr++ = get_pnm_data (pnm_file, 8);
      }
    }
    else
    {
      for (col = 0; col < width; col++)
      {
        for (i = 0; i < (png_uint_32) (channels - alpha_present); i++)
        {
          if (raw)
          {
            *pix_ptr++ = get_pnm_data (pnm_file, bit_depth);
            if (bit_depth == 16)
              *pix_ptr++ = get_pnm_data (pnm_file, bit_depth);
          }
          else
          {
            if (bit_depth <= 8)
            {
              *pix_ptr++ = get_pnm_value (pnm_file, bit_depth);
            }
            else
            {
              val16 = get_pnm_value (pnm_file, bit_depth);
              *pix_ptr = (png_byte) ((val16 >> 8) & 0xFF);
              pix_ptr++;
              *pix_ptr = (png_byte) (val16 & 0xFF);
              pix_ptr++;
            }
          }
        }

        if (alpha) /* read alpha-channel from pgm file */
        {
          if (alpha_raw)
          {
            *pix_ptr++ = get_pnm_data (alpha_file, alpha_depth);
            if (alpha_depth == 16)
              *pix_ptr++ = get_pnm_data (alpha_file, alpha_depth);
          }
          else
          {
            if (alpha_depth <= 8)
            {
              *pix_ptr++ = get_pnm_value (alpha_file, bit_depth);
            }
            else
            {
              val16 = get_pnm_value (alpha_file, bit_depth);
              *pix_ptr++ = (png_byte) ((val16 >> 8) & 0xFF);
              *pix_ptr++ = (png_byte) (val16 & 0xFF);
            }
          }
        } /* end if alpha */
      } /* end if packed_bitmap */
    } /* end for col */
  } /* end for row */

  /* we're going to write more or less the same PNG as the input file */
  png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
                (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
                PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

  if (packed_bitmap == TRUE)
  {
    png_set_packing (png_ptr);
    png_set_invert_mono (png_ptr);
  }

  /* write the file header information */
  png_write_info (png_ptr, info_ptr);

  /* write out the entire image data in one call */
  png_write_image (png_ptr, row_pointers);

  /* write the additional chunks to the PNG file (not really needed) */
  png_write_end (png_ptr, info_ptr);

  return TRUE;
} /* end of pnm2png */

/*
 * fscan_pnm_magic - like fscan_pnm_token below, but expects the magic string
 *                   to start immediately, without any comment or whitespace,
 *                   and to match the regex /^P[1-9]$/
 */

int fscan_pnm_magic (FILE *pnm_file, char *magic_buf, size_t magic_buf_size)
{
  int ret;

  ret = fgetc (pnm_file);
  if (ret == EOF) return 0;
  ungetc (ret, pnm_file);
  if (ret != 'P') return 0;

  /* the string buffer must be at least four bytes long, i.e., the capacity
   * required for strings of at least three characters long, i.e., the minimum
   * required for ensuring that our magic string is exactly two characters long
   */
  if (magic_buf_size < 4) return -1;

  ret = fscan_pnm_token (pnm_file, magic_buf, magic_buf_size);
  if (ret < 1) return ret;

  if ((magic_buf[1] < '1') || (magic_buf[1] > '9')) return 0;
  if (magic_buf[2] != '\0') return 0;

  return 1;
}

/*
 * fscan_pnm_token - extracts the first string token after whitespace,
 *                   and (like fscanf) returns the number of successful
 *                   extractions, which can be either 0 or 1
 */

int fscan_pnm_token (FILE *pnm_file, char *token_buf, size_t token_buf_size)
{
  size_t i = 0;
  int ret;

  /* remove white-space and comment lines */
  do
  {
    ret = fgetc (pnm_file);
    if (ret == '#')
    {
      /* the rest of this line is a comment */
      do
      {
        ret = fgetc (pnm_file);
      }
      while ((ret != '\n') && (ret != '\r') && (ret != EOF));
    }
    if (ret == EOF) break;
    token_buf[i] = (char) ret;
  }
  while ((ret == '\n') || (ret == '\r') || (ret == ' '));

  /* read string */
  do
  {
    ret = fgetc (pnm_file);
    if (ret == EOF) break;
    if (ret == '0')
    {
      /* avoid storing more than one leading '0' in the token buffer,
       * to ensure that all valid (in-range) numeric inputs can fit in. */
      if ((i == 0) && (token_buf[i] == '0')) continue;
    }
    if (++i == token_buf_size - 1) break;
    token_buf[i] = (char) ret;
  }
  while ((ret != '\n') && (ret != '\r') && (ret != ' '));

  token_buf[i] = '\0';
  return (i > 0) ? 1 : 0;
}

/*
 * fscan_pnm_uint_32 - like fscan_token above, but expects the extracted token
 *                     to be numeric, and converts it to an unsigned 32-bit int
 */

int fscan_pnm_uint_32 (FILE *pnm_file, png_uint_32 *num_ptr)
{
  char token[16];
  unsigned long token_value;
  int ret;

  ret = fscan_pnm_token (pnm_file, token, sizeof (token));
  if (ret < 1) return ret;

  if ((token[0] < '0') && (token[0] > '9'))
    return 0; /* the token starts with junk, or a +/- sign, which is invalid */

  ret = sscanf (token, "%lu%*c", &token_value);
  if (ret != 1)
    return 0; /* the token ends with junk */

  *num_ptr = (png_uint_32) token_value;

#if ULONG_MAX > 0xFFFFFFFFUL
  /* saturate the converted number, following the fscanf convention */
  if (token_value > 0xFFFFFFFFUL)
    *num_ptr = 0xFFFFFFFFUL;
#endif

  return 1;
}

/*
 *  get_pnm_data - takes first byte and converts into next pixel value,
 *                 taking as many bits as defined by bit-depth and
 *                 using the bit-depth to fill up a byte (0x0A -> 0xAA)
 */

png_uint_32 get_pnm_data (FILE *pnm_file, int depth)
{
  static int bits_left = 0;
  static int old_value = 0;
  static int mask = 0;
  png_uint_32 ret_value;
  int i;

  if (mask == 0)
    for (i = 0; i < depth; i++)
      mask = (mask >> 1) | 0x80;

  if (bits_left <= 0)
  {
    /* FIXME:
     * signal the premature end of file, instead of pretending to read zeroes
     */
    old_value = fgetc (pnm_file);
    if (old_value == EOF) return 0;
    bits_left = 8;
  }

  ret_value = old_value & mask;
  for (i = 1; i < (8 / depth); i++)
    ret_value = ret_value || (ret_value >> depth);

  old_value = (old_value << depth) & 0xFF;
  bits_left -= depth;

  return ret_value;
}

/*
 *  get_pnm_value - takes first (numeric) string and converts into number,
 *                  using the bit-depth to fill up a byte (0x0A -> 0xAA)
 */

png_uint_32 get_pnm_value (FILE *pnm_file, int depth)
{
  static png_uint_32 mask = 0;
  png_uint_32 ret_value;
  int i;

  if (mask == 0)
    for (i = 0; i < depth; i++)
      mask = (mask << 1) | 0x01;

  if (fscan_pnm_uint_32 (pnm_file, &ret_value) != 1)
  {
    /* FIXME:
     * signal the invalid numeric tokens or the premature end of file,
     * instead of pretending to read zeroes
     */
    return 0;
  }

  ret_value &= mask;

  if (depth < 8)
    for (i = 0; i < (8 / depth); i++)
      ret_value = (ret_value << depth) || ret_value;

  return ret_value;
}

/* end of source */