1 /*
2 * pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
3 * copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
4 *
5 * version 1.0 - 1999.10.15 - First version.
6 *
7 * Permission to use, copy, modify, and distribute this software and
8 * its documentation for any purpose and without fee is hereby granted,
9 * provided that the above copyright notice appear in all copies and
10 * that both that copyright notice and this permission notice appear in
11 * supporting documentation. This software is provided "as is" without
12 * express or implied warranty.
13 */
14
15 #include <stdio.h>
16 #include <stdlib.h>
17 #ifdef __TURBOC__
18 #include <mem.h>
19 #include <fcntl.h>
20 #endif
21 #include <zlib.h>
22
23 #ifndef BOOL
24 #define BOOL unsigned char
25 #endif
26 #ifndef TRUE
27 #define TRUE (BOOL) 1
28 #endif
29 #ifndef FALSE
30 #define FALSE (BOOL) 0
31 #endif
32
33 #define STDIN 0
34 #define STDOUT 1
35 #define STDERR 2
36
37 /* to make pnm2png verbose so we can find problems (needs to be before png.h) */
38 #ifndef PNG_DEBUG
39 #define PNG_DEBUG 0
40 #endif
41
42 #include "png.h"
43
44 /* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
45 #ifndef png_jmpbuf
46 # define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
47 #endif
48
49 /* function prototypes */
50
51 int main (int argc, char *argv[]);
52 void usage ();
53 BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);
54 void get_token(FILE *pnm_file, char *token);
55 png_uint_32 get_data (FILE *pnm_file, int depth);
56 png_uint_32 get_value (FILE *pnm_file, int depth);
57
58 /*
59 * main
60 */
61
main(int argc,char * argv[])62 int main(int argc, char *argv[])
63 {
64 FILE *fp_rd = stdin;
65 FILE *fp_al = NULL;
66 FILE *fp_wr = stdout;
67 BOOL interlace = FALSE;
68 BOOL alpha = FALSE;
69 int argi;
70
71 for (argi = 1; argi < argc; argi++)
72 {
73 if (argv[argi][0] == '-')
74 {
75 switch (argv[argi][1])
76 {
77 case 'i':
78 interlace = TRUE;
79 break;
80 case 'a':
81 alpha = TRUE;
82 argi++;
83 if ((fp_al = fopen (argv[argi], "rb")) == NULL)
84 {
85 fprintf (stderr, "PNM2PNG\n");
86 fprintf (stderr, "Error: alpha-channel file %s does not exist\n",
87 argv[argi]);
88 exit (1);
89 }
90 break;
91 case 'h':
92 case '?':
93 usage();
94 exit(0);
95 break;
96 default:
97 fprintf (stderr, "PNM2PNG\n");
98 fprintf (stderr, "Error: unknown option %s\n", argv[argi]);
99 usage();
100 exit(1);
101 break;
102 } /* end switch */
103 }
104 else if (fp_rd == stdin)
105 {
106 if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
107 {
108 fprintf (stderr, "PNM2PNG\n");
109 fprintf (stderr, "Error: file %s does not exist\n", argv[argi]);
110 exit (1);
111 }
112 }
113 else if (fp_wr == stdout)
114 {
115 if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
116 {
117 fprintf (stderr, "PNM2PNG\n");
118 fprintf (stderr, "Error: can not create PNG-file %s\n", argv[argi]);
119 exit (1);
120 }
121 }
122 else
123 {
124 fprintf (stderr, "PNM2PNG\n");
125 fprintf (stderr, "Error: too many parameters\n");
126 usage();
127 exit (1);
128 }
129 } /* end for */
130
131 #ifdef __TURBOC__
132 /* set stdin/stdout to binary, we're reading the PNM always! in binary format */
133 if (fp_rd == stdin)
134 {
135 setmode (STDIN, O_BINARY);
136 }
137 if (fp_wr == stdout)
138 {
139 setmode (STDOUT, O_BINARY);
140 }
141 #endif
142
143 /* call the conversion program itself */
144 if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
145 {
146 fprintf (stderr, "PNM2PNG\n");
147 fprintf (stderr, "Error: unsuccessful converting to PNG-image\n");
148 exit (1);
149 }
150
151 /* close input file */
152 fclose (fp_rd);
153 /* close output file */
154 fclose (fp_wr);
155 /* close alpha file */
156 if (alpha)
157 fclose (fp_al);
158
159 return 0;
160 }
161
162 /*
163 * usage
164 */
165
usage()166 void usage()
167 {
168 fprintf (stderr, "PNM2PNG\n");
169 fprintf (stderr, " by Willem van Schaik, 1999\n");
170 #ifdef __TURBOC__
171 fprintf (stderr, " for Turbo-C and Borland-C compilers\n");
172 #else
173 fprintf (stderr, " for Linux (and Unix) compilers\n");
174 #endif
175 fprintf (stderr, "Usage: pnm2png [options] <file>.<pnm> [<file>.png]\n");
176 fprintf (stderr, " or: ... | pnm2png [options]\n");
177 fprintf (stderr, "Options:\n");
178 fprintf (stderr, " -i[nterlace] write png-file with interlacing on\n");
179 fprintf (stderr, " -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
180 fprintf (stderr, " -h | -? print this help-information\n");
181 }
182
183 /*
184 * pnm2png
185 */
186
pnm2png(FILE * pnm_file,FILE * png_file,FILE * alpha_file,BOOL interlace,BOOL alpha)187 BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha)
188 {
189 png_struct *png_ptr = NULL;
190 png_info *info_ptr = NULL;
191 png_byte *png_pixels = NULL;
192 png_byte **row_pointers = NULL;
193 png_byte *pix_ptr = NULL;
194 png_uint_32 row_bytes;
195
196 char type_token[16];
197 char width_token[16];
198 char height_token[16];
199 char maxval_token[16];
200 int color_type;
201 unsigned long ul_width=0, ul_alpha_width=0;
202 unsigned long ul_height=0, ul_alpha_height=0;
203 unsigned long ul_maxval=0;
204 png_uint_32 width, alpha_width;
205 png_uint_32 height, alpha_height;
206 png_uint_32 maxval;
207 int bit_depth = 0;
208 int channels;
209 int alpha_depth = 0;
210 int alpha_present;
211 int row, col;
212 BOOL raw, alpha_raw = FALSE;
213 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
214 BOOL packed_bitmap = FALSE;
215 #endif
216 png_uint_32 tmp16;
217 int i;
218
219 /* read header of PNM file */
220
221 get_token(pnm_file, type_token);
222 if (type_token[0] != 'P')
223 {
224 return FALSE;
225 }
226 else if ((type_token[1] == '1') || (type_token[1] == '4'))
227 {
228 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
229 raw = (type_token[1] == '4');
230 color_type = PNG_COLOR_TYPE_GRAY;
231 get_token(pnm_file, width_token);
232 sscanf (width_token, "%lu", &ul_width);
233 width = (png_uint_32) ul_width;
234 get_token(pnm_file, height_token);
235 sscanf (height_token, "%lu", &ul_height);
236 height = (png_uint_32) ul_height;
237 bit_depth = 1;
238 packed_bitmap = TRUE;
239 #else
240 fprintf (stderr, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and \n");
241 fprintf (stderr, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
242 #endif
243 }
244 else if ((type_token[1] == '2') || (type_token[1] == '5'))
245 {
246 raw = (type_token[1] == '5');
247 color_type = PNG_COLOR_TYPE_GRAY;
248 get_token(pnm_file, width_token);
249 sscanf (width_token, "%lu", &ul_width);
250 width = (png_uint_32) ul_width;
251 get_token(pnm_file, height_token);
252 sscanf (height_token, "%lu", &ul_height);
253 height = (png_uint_32) ul_height;
254 get_token(pnm_file, maxval_token);
255 sscanf (maxval_token, "%lu", &ul_maxval);
256 maxval = (png_uint_32) ul_maxval;
257
258 if (maxval <= 1)
259 bit_depth = 1;
260 else if (maxval <= 3)
261 bit_depth = 2;
262 else if (maxval <= 15)
263 bit_depth = 4;
264 else if (maxval <= 255)
265 bit_depth = 8;
266 else /* if (maxval <= 65535) */
267 bit_depth = 16;
268 }
269 else if ((type_token[1] == '3') || (type_token[1] == '6'))
270 {
271 raw = (type_token[1] == '6');
272 color_type = PNG_COLOR_TYPE_RGB;
273 get_token(pnm_file, width_token);
274 sscanf (width_token, "%lu", &ul_width);
275 width = (png_uint_32) ul_width;
276 get_token(pnm_file, height_token);
277 sscanf (height_token, "%lu", &ul_height);
278 height = (png_uint_32) ul_height;
279 get_token(pnm_file, maxval_token);
280 sscanf (maxval_token, "%lu", &ul_maxval);
281 maxval = (png_uint_32) ul_maxval;
282 if (maxval <= 1)
283 bit_depth = 1;
284 else if (maxval <= 3)
285 bit_depth = 2;
286 else if (maxval <= 15)
287 bit_depth = 4;
288 else if (maxval <= 255)
289 bit_depth = 8;
290 else /* if (maxval <= 65535) */
291 bit_depth = 16;
292 }
293 else
294 {
295 return FALSE;
296 }
297
298 /* read header of PGM file with alpha channel */
299
300 if (alpha)
301 {
302 if (color_type == PNG_COLOR_TYPE_GRAY)
303 color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
304 if (color_type == PNG_COLOR_TYPE_RGB)
305 color_type = PNG_COLOR_TYPE_RGB_ALPHA;
306
307 get_token(alpha_file, type_token);
308 if (type_token[0] != 'P')
309 {
310 return FALSE;
311 }
312 else if ((type_token[1] == '2') || (type_token[1] == '5'))
313 {
314 alpha_raw = (type_token[1] == '5');
315 get_token(alpha_file, width_token);
316 sscanf (width_token, "%lu", &ul_alpha_width);
317 alpha_width=(png_uint_32) ul_alpha_width;
318 if (alpha_width != width)
319 return FALSE;
320 get_token(alpha_file, height_token);
321 sscanf (height_token, "%lu", &ul_alpha_height);
322 alpha_height = (png_uint_32) ul_alpha_height;
323 if (alpha_height != height)
324 return FALSE;
325 get_token(alpha_file, maxval_token);
326 sscanf (maxval_token, "%lu", &ul_maxval);
327 maxval = (png_uint_32) ul_maxval;
328 if (maxval <= 1)
329 alpha_depth = 1;
330 else if (maxval <= 3)
331 alpha_depth = 2;
332 else if (maxval <= 15)
333 alpha_depth = 4;
334 else if (maxval <= 255)
335 alpha_depth = 8;
336 else /* if (maxval <= 65535) */
337 alpha_depth = 16;
338 if (alpha_depth != bit_depth)
339 return FALSE;
340 }
341 else
342 {
343 return FALSE;
344 }
345 } /* end if alpha */
346
347 /* calculate the number of channels and store alpha-presence */
348 if (color_type == PNG_COLOR_TYPE_GRAY)
349 channels = 1;
350 else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
351 channels = 2;
352 else if (color_type == PNG_COLOR_TYPE_RGB)
353 channels = 3;
354 else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
355 channels = 4;
356 else
357 channels = 0; /* should not happen */
358
359 alpha_present = (channels - 1) % 2;
360
361 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
362 if (packed_bitmap)
363 /* row data is as many bytes as can fit width x channels x bit_depth */
364 row_bytes = (width * channels * bit_depth + 7) / 8;
365 else
366 #endif
367 /* row_bytes is the width x number of channels x (bit-depth / 8) */
368 row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
369
370 if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
371 return FALSE;
372
373 /* read data from PNM file */
374 pix_ptr = png_pixels;
375
376 for (row = 0; row < height; row++)
377 {
378 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
379 if (packed_bitmap) {
380 for (i = 0; i < row_bytes; i++)
381 /* png supports this format natively so no conversion is needed */
382 *pix_ptr++ = get_data (pnm_file, 8);
383 } else
384 #endif
385 {
386 for (col = 0; col < width; col++)
387 {
388 for (i = 0; i < (channels - alpha_present); i++)
389 {
390 if (raw)
391 *pix_ptr++ = get_data (pnm_file, bit_depth);
392 else
393 if (bit_depth <= 8)
394 *pix_ptr++ = get_value (pnm_file, bit_depth);
395 else
396 {
397 tmp16 = get_value (pnm_file, bit_depth);
398 *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
399 pix_ptr++;
400 *pix_ptr = (png_byte) (tmp16 & 0xFF);
401 pix_ptr++;
402 }
403 }
404
405 if (alpha) /* read alpha-channel from pgm file */
406 {
407 if (alpha_raw)
408 *pix_ptr++ = get_data (alpha_file, alpha_depth);
409 else
410 if (alpha_depth <= 8)
411 *pix_ptr++ = get_value (alpha_file, bit_depth);
412 else
413 {
414 tmp16 = get_value (alpha_file, bit_depth);
415 *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
416 *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
417 }
418 } /* if alpha */
419 } /* if packed_bitmap */
420 } /* end for col */
421 } /* end for row */
422
423 /* prepare the standard PNG structures */
424 png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
425 if (!png_ptr)
426 {
427 return FALSE;
428 }
429 info_ptr = png_create_info_struct (png_ptr);
430 if (!info_ptr)
431 {
432 png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
433 return FALSE;
434 }
435
436 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
437 if (packed_bitmap == TRUE)
438 {
439 png_set_packing (png_ptr);
440 png_set_invert_mono (png_ptr);
441 }
442 #endif
443
444 /* setjmp() must be called in every function that calls a PNG-reading libpng function */
445 if (setjmp (png_jmpbuf(png_ptr)))
446 {
447 png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
448 return FALSE;
449 }
450
451 /* initialize the png structure */
452 png_init_io (png_ptr, png_file);
453
454 /* we're going to write more or less the same PNG as the input file */
455 png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
456 (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
457 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
458
459 /* write the file header information */
460 png_write_info (png_ptr, info_ptr);
461
462 /* if needed we will allocate memory for an new array of row-pointers */
463 if (row_pointers == (unsigned char**) NULL)
464 {
465 if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)
466 {
467 png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
468 return FALSE;
469 }
470 }
471
472 /* set the individual row_pointers to point at the correct offsets */
473 for (i = 0; i < (height); i++)
474 row_pointers[i] = png_pixels + i * row_bytes;
475
476 /* write out the entire image data in one call */
477 png_write_image (png_ptr, row_pointers);
478
479 /* write the additional chuncks to the PNG file (not really needed) */
480 png_write_end (png_ptr, info_ptr);
481
482 /* clean up after the write, and free any memory allocated */
483 png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
484
485 if (row_pointers != (unsigned char**) NULL)
486 free (row_pointers);
487 if (png_pixels != (unsigned char*) NULL)
488 free (png_pixels);
489
490 return TRUE;
491 } /* end of pnm2png */
492
493 /*
494 * get_token() - gets the first string after whitespace
495 */
496
get_token(FILE * pnm_file,char * token)497 void get_token(FILE *pnm_file, char *token)
498 {
499 int i = 0;
500 int ret;
501
502 /* remove white-space and comment lines */
503 do
504 {
505 ret = fgetc(pnm_file);
506 if (ret == '#') {
507 /* the rest of this line is a comment */
508 do
509 {
510 ret = fgetc(pnm_file);
511 }
512 while ((ret != '\n') && (ret != '\r') && (ret != EOF));
513 }
514 if (ret == EOF) break;
515 token[i] = (unsigned char) ret;
516 }
517 while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
518
519 /* read string */
520 do
521 {
522 ret = fgetc(pnm_file);
523 if (ret == EOF) break;
524 i++;
525 token[i] = (unsigned char) ret;
526 }
527 while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
528
529 token[i] = '\0';
530
531 return;
532 }
533
534 /*
535 * get_data() - takes first byte and converts into next pixel value,
536 * taking as much bits as defined by bit-depth and
537 * using the bit-depth to fill up a byte (0Ah -> AAh)
538 */
539
get_data(FILE * pnm_file,int depth)540 png_uint_32 get_data (FILE *pnm_file, int depth)
541 {
542 static int bits_left = 0;
543 static int old_value = 0;
544 static int mask = 0;
545 int i;
546 png_uint_32 ret_value;
547
548 if (mask == 0)
549 for (i = 0; i < depth; i++)
550 mask = (mask >> 1) | 0x80;
551
552 if (bits_left <= 0)
553 {
554 old_value = fgetc (pnm_file);
555 bits_left = 8;
556 }
557
558 ret_value = old_value & mask;
559 for (i = 1; i < (8 / depth); i++)
560 ret_value = ret_value || (ret_value >> depth);
561
562 old_value = (old_value << depth) & 0xFF;
563 bits_left -= depth;
564
565 return ret_value;
566 }
567
568 /*
569 * get_value() - takes first (numeric) string and converts into number,
570 * using the bit-depth to fill up a byte (0Ah -> AAh)
571 */
572
get_value(FILE * pnm_file,int depth)573 png_uint_32 get_value (FILE *pnm_file, int depth)
574 {
575 static png_uint_32 mask = 0;
576 png_byte token[16];
577 unsigned long ul_ret_value;
578 png_uint_32 ret_value;
579 int i = 0;
580
581 if (mask == 0)
582 for (i = 0; i < depth; i++)
583 mask = (mask << 1) | 0x01;
584
585 get_token (pnm_file, (char *) token);
586 sscanf ((const char *) token, "%lu", &ul_ret_value);
587 ret_value = (png_uint_32) ul_ret_value;
588
589 ret_value &= mask;
590
591 if (depth < 8)
592 for (i = 0; i < (8 / depth); i++)
593 ret_value = (ret_value << depth) || ret_value;
594
595 return ret_value;
596 }
597
598 /* end of source */
599
600