comparison Meerwald/wm_bruyn_e.c @ 0:be303a3f5ea8

import
author Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date Sun, 12 Aug 2007 13:14:34 +0200
parents
children f83ef905a63d
comparison
equal deleted inserted replaced
-1:000000000000 0:be303a3f5ea8
1 #include "wm.h"
2 #include "signature.h"
3 #include "coord.h"
4 #include "gray.h"
5 #include "sort.h"
6 #include "bruyn_common.h"
7 #include "pgm.h"
8
9 char *progname;
10
11 // prints out program's parameters
12 void usage(void) {
13 fprintf(stderr, "usage: %s [-b n] [-h] [-k] [-n n] [-o file] [-pP n] [-q n] [-tT n] [-v n] -s file file\n", progname);
14 fprintf(stderr, "\t-b n\t\tblock size\n");
15 fprintf(stderr, "\t-h\t\tprint usage\n");
16 fprintf(stderr, "\t-k\t\tdisable block skipping\n");
17 fprintf(stderr, "\t-n n\t\tnumber of signature bits to embed\n");
18 fprintf(stderr, "\t-o file\t\toutput (watermarked) file\n");
19 fprintf(stderr, "\t-p n\t\tpattern type for zone 1\n");
20 fprintf(stderr, "\t-P n\t\tpattern type for zone 2\n");
21 fprintf(stderr, "\t-q n\t\tsignature strength\n");
22 fprintf(stderr, "\t-s file\t\tsignature to embed in input image\n");
23 fprintf(stderr, "\t-t n\t\tthreshold for noise\n");
24 fprintf(stderr, "\t-T n\t\tthreshold for slope\n");
25 fprintf(stderr, "\t-v n\t\tverbosity level\n");
26 exit(0);
27 }
28
29 int main(int argc, char *argv[]) {
30 FILE *in = stdin;
31 FILE *out = stdout;
32 FILE *sig = NULL;
33
34 gray** image;
35 gray **block;
36 gray **zone;
37 gray **category1, **category2;
38 gray maxval;
39 double *slope;
40 int rows, cols, colors, format;
41 int c;
42 int i, j;
43 int r;
44 int n;
45 int col, row;
46 int bwidth, bheight;
47 int n_block;
48 int skipping = 0;
49
50 char signature_name[MAXPATHLEN];
51 char input_name[MAXPATHLEN] = "(stdin)";
52 char output_name[MAXPATHLEN] = "(stdout)";
53
54 double quality = 0.0;
55 double threshold_noise = 0.0;
56 double threshold_slope = 0.0;
57 int pattern1 = 0;
58 int pattern2 = 0;
59 int blocksize = 0;
60 int seed;
61
62 int verbose = 0;
63
64 struct coords *coords;
65
66 progname = argv[0];
67
68 pgm_init(&argc, argv); wm_init();
69
70 // parse command line and set options
71 while ((c = getopt(argc, argv, "b:h?n:o:p:P:q:s:t:T:v:k")) != EOF) {
72 switch (c) {
73 case 'k':
74 skipping = 1;
75 break;
76 case 'h':
77 case '?':
78 usage();
79 break;
80 case 'n':
81 nbit_signature = atoi(optarg);
82 if (nbit_signature <= 0 || nbit_signature > NBITSIGNATURE) {
83 fprintf(stderr, "%s: invalid signature length %d\n", progname, nbit_signature);
84 exit(1);
85 }
86 break;
87 case 'o':
88 if ((out = fopen(optarg, "wb")) == NULL) {
89 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg);
90 exit(1);
91 }
92 strcpy(output_name, optarg);
93 break;
94 case 'p':
95 pattern1 = atoi(optarg);
96 if (pattern1 <= 0 || pattern1 > NPATTERN) {
97 fprintf(stderr, "%s: pattern type out of range\n", progname);
98 exit(1);
99 }
100 break;
101 case 'P':
102 pattern2 = atoi(optarg);
103 if (pattern2 <= 0 || pattern2 > 3) {
104 fprintf(stderr, "%s: pattern type out of range\n", progname);
105 exit(1);
106 }
107 break;
108 case 'q':
109 quality = atof(optarg);
110 if (quality <= 0) {
111 fprintf(stderr, "%s: quality factor %f out of range\n", progname, quality);
112 }
113 break;
114 case 's':
115 if ((sig = fopen(optarg, "r")) == NULL) {
116 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg);
117 exit(1);
118 }
119 strcpy(signature_name, optarg);
120 break;
121 case 't':
122 threshold_noise = atof(optarg);
123 if (threshold_noise <= 0) {
124 fprintf(stderr, "%s: noise threshold %f out of range\n", progname, threshold_noise);
125 }
126 break;
127 case 'T':
128 threshold_slope = atof(optarg);
129 if (threshold_slope <= 0) {
130 fprintf(stderr, "%s: slope threshold %f out of range\n", progname, threshold_slope);
131 }
132 break;
133 case 'v':
134 verbose = atoi(optarg);
135 if (verbose < 0) {
136 fprintf(stderr, "%s: verbosity level %d out of range\n",progname, verbose);
137 exit(1);
138 }
139 break;
140 }
141 }
142
143 argc -= optind;
144 argv += optind;
145
146 if (argc > 1) {
147 usage();
148 exit(1);
149 }
150
151 // open input image file or read from stdin
152 if (argc == 1 && *argv[0] != '-')
153 if ((in = fopen(argv[0], "rb")) == NULL) {
154 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]);
155 exit(1);
156 }
157 else
158 strcpy(input_name, argv[0]);
159
160 // read signature file and set options
161 // command line options override signature file options
162 if (sig) {
163 char line[128];
164 fgets(line, sizeof(line), sig);
165 if (strspn(line, "BRSG") >= 4) {
166 if (nbit_signature == 0)
167 fscanf(sig, "%d\n", &nbit_signature);
168 else
169 fscanf(sig, "%*d\n");
170 if (skipping == 0)
171 fscanf(sig, "%d\n", &skipping);
172 else
173 fscanf(sig, "%*d\n");
174 if (pattern1 == 0)
175 fscanf(sig, "%d\n", &pattern1);
176 else
177 fscanf(sig, "%*d\n");
178 if (pattern2 == 0)
179 fscanf(sig, "%d\n", &pattern2);
180 else
181 fscanf(sig, "%*d\n");
182 if (quality == 0.0)
183 fscanf(sig, "%lf\n", &quality);
184 else
185 fscanf(sig, "%*lf\n");
186 if (threshold_noise == 0.0)
187 fscanf(sig, "%lf\n", &threshold_noise);
188 else
189 fscanf(sig, "%*lf\n");
190 if (threshold_slope == 0.0)
191 fscanf(sig, "%lf\n", &threshold_slope);
192 else
193 fscanf(sig, "%*lf\n");
194 if (blocksize == 0)
195 fscanf(sig, "%d\n", &blocksize);
196 else
197 fscanf(sig, "%*d\n");
198 fscanf(sig, "%d\n", &seed);
199 srandom(seed);
200 n_signature = NBITSTOBYTES(nbit_signature);
201 fread(signature, sizeof(char), n_signature, sig);
202 fscanf(sig, "\n");
203 }
204 else {
205 fprintf(stderr, "%s: invalid signature file %s\n", progname, signature_name);
206 exit(1);
207 }
208 fclose(sig);
209 }
210 else {
211 fprintf(stderr, "%s: signature file not specified, use -s file option\n", progname);
212 exit(1);
213 }
214
215 if (pattern1 <= 0 || pattern2 <= 0 || pattern1 > NPATTERN || pattern2 > NPATTERN) {
216 fprintf(stderr, "%s: invalid pattern type specified\n");
217 exit(1);
218 }
219
220 // read dimensions of input image file
221 pgm_readpgminit(in, &cols, &rows, &maxval, &format);
222
223 // see if we can embed all signature bits
224 // we want at least half of the blocks untouched
225 if (((rows / blocksize) * (cols / blocksize)) < nbit_signature / 2) {
226 fprintf(stderr, "%s: image not large enough to embed %d bits of signature\n", progname, nbit_signature);
227 exit(1);
228 }
229 n_block = blocksize * blocksize;
230
231 // allocate structure to remember which blocks we already touched,
232 // allow plenty of room to skip over blocks
233 if ((coords = alloc_coords(nbit_signature * 2)) == NULL) {
234 fprintf(stderr, "%s: unable to allocate memory\n", progname);
235 exit(1);
236 }
237
238 // read in input image file
239 image = pgm_allocarray(cols, rows);
240 for (row = 0; row < rows; row++)
241 pgm_readpgmrow(in, image[row], cols, maxval, format);
242
243 fclose(in);
244
245 row = 0;
246 col = 0;
247
248 // allocate memory for one block
249 block = alloc_grays(blocksize, blocksize);
250
251 // allocate memory for zone classification
252 zone = alloc_grays(blocksize, blocksize);
253
254 // allocate memory for category classification
255 category1 = alloc_grays(blocksize, blocksize);
256 category2 = alloc_grays(blocksize, blocksize);
257
258 // set up category classification array according to
259 // pattern type parameter
260 for (i = 0; i < blocksize; i++)
261 for (j = 0; j < blocksize; j++) {
262 category1[j][i] = lookup_pattern(pattern1, i, j);
263 category2[j][i] = lookup_pattern(pattern2, i, j);
264 }
265
266 // allocate memory for slope calculation
267 slope = malloc(sizeof(double) * n_block);
268
269 // embed all the signature bits, one by one
270 n = 0;
271 while (n < nbit_signature) {
272 int xb;
273 int yb;
274 int blocktype;
275 double smax;
276 int alpha, beta_minus, beta_plus;
277 double mean_1A, mean_1B, mean_2A, mean_2B, mean_1, mean_2;
278 double mean__1A, mean__1B, mean__2A, mean__2B;
279 int n_1A, n_1B, n_2A, n_2B, n_1, n_2;
280 int var_1A, var_1B, var_2A, var_2B;
281 int zone1_ok, zone2_ok;
282
283 // find an unused block randomly, depending on seed
284 do {
285 xb = random() % (cols / blocksize);
286 yb = random() % (rows / blocksize);
287 } while (add_coord(coords, xb, yb) < 0);
288
289 // copy image block
290 copy_grays_to_block(block, image, xb * blocksize, yb * blocksize, blocksize, blocksize);
291
292 if (verbose > 0)
293 fprintf(stderr, "embedding bit #%d (= %d) in block at (%d/%d)\n", n, get_signature_bit(n), xb * blocksize, yb * blocksize);
294 if (verbose > 8) {
295 print_grays(image, xb * blocksize, yb * blocksize, blocksize, blocksize);
296 fprintf(stderr, "\n");
297 }
298
299 // sort luminance values in block to represent increasing function F
300 sort_grays(block[0], n_block);
301
302 if (verbose > 8) {
303 print_grays(block, 0, 0, blocksize, blocksize);
304 fprintf(stderr, "\n");
305 }
306
307 // calculate slopes of F and determine smax, the max. slope of F
308 // the index where smax occures is called alpha
309 alpha = 0;
310 smax = 0.0;
311 for (i = 0; i < n_block - 1; i++) {
312 slope[i] = block[0][i + 1] - block[0][i];
313 if (slope[i] > smax) {
314 smax = slope[i];
315 alpha = i;
316 }
317 }
318 slope[n_block - 1] = 0;
319
320 // block type classification
321 blocktype = BLOCKTYPE_UNKNOWN;
322
323 if (smax < threshold_noise) {
324 // block has noise contrast
325
326 blocktype = BLOCKTYPE_NOISE;
327 beta_minus = beta_plus = alpha;
328 }
329 else {
330 // block has progressive or hard contrast, let's find out...
331
332 beta_minus = alpha - 1;
333 while (beta_minus >= 0 && smax - slope[beta_minus] <= threshold_slope)
334 beta_minus--;
335
336 beta_plus = alpha + 1;
337 while (beta_plus < n_block && smax - slope[beta_plus] <= threshold_slope)
338 beta_plus++;
339
340 if (beta_minus + 1 == alpha && beta_plus - 1 == alpha)
341 blocktype = BLOCKTYPE_HARD;
342 else
343 blocktype = BLOCKTYPE_PROGRESSIVE;
344 }
345
346 if (verbose > 1) {
347 fprintf(stderr, "blocktype: %d\n", blocktype);
348 fprintf(stderr, "Smax = %lf, alpha = %d, beta- = %d, beta+ = %d\n", smax, alpha, beta_minus, beta_plus);
349 }
350
351 // block pixel classification
352 for (i = 0; i < blocksize; i++)
353 for (j = 0; j < blocksize; j++) {
354 gray pixel = image[yb * blocksize + j][xb * blocksize + i];
355 zone[j][i] = ZONE_VOID;
356 switch (blocktype) {
357 case BLOCKTYPE_PROGRESSIVE:
358 case BLOCKTYPE_HARD:
359 if (pixel < block[0][beta_minus])
360 zone[j][i] = ZONE_1;
361 else if (pixel > block[0][beta_plus])
362 zone[j][i] = ZONE_2;
363 break;
364 case BLOCKTYPE_NOISE:
365 if (pixel < block[0][n_block / 2])
366 zone[j][i] = ZONE_1;
367 else if (pixel > block[0][n_block / 2])
368 zone[j][i] = ZONE_2;
369 break;
370 default:
371 fprintf(stderr, "%s: invalid block type\n", progname);
372 break;
373 }
374 }
375
376 if (verbose > 8) {
377 print_grays(zone, 0, 0, blocksize, blocksize);
378 fprintf(stderr, "\n");
379 }
380
381 // calculate mean values for zone/categories
382 mean_1A = mean_1B = mean_2A = mean_2B = mean_1 = mean_2 = 0.0;
383 n_1A = n_1B = n_2A = n_2B = n_1 = n_2 = 0;
384 for (i = 0; i < blocksize; i++)
385 for (j = 0; j < blocksize; j++) {
386 gray pixel = image[yb * blocksize + j][xb * blocksize + i];
387 int pixel_zone = zone[j][i];
388 int pixel_category = CATEGORY_VOID;
389 if (pixel_zone == ZONE_1)
390 pixel_category = category1[j][i];
391 else if (pixel_zone == ZONE_2)
392 pixel_category = category2[j][i];
393
394 switch (pixel_zone | pixel_category) {
395 case CLASSIFICATION_1A:
396 n_1++;
397 n_1A++;
398 mean_1A += pixel;
399 mean_1 += pixel;
400 break;
401 case CLASSIFICATION_1B:
402 n_1++;
403 n_1B++;
404 mean_1B += pixel;
405 mean_1 += pixel;
406 break;
407 case CLASSIFICATION_2A:
408 n_2++;
409 n_2A++;
410 mean_2A += pixel;
411 mean_2 += pixel;
412 break;
413 case CLASSIFICATION_2B:
414 n_2++;
415 n_2B++;
416 mean_2B += pixel;
417 mean_2 += pixel;
418 break;
419 }
420 }
421
422 if (n_1 && n_1A && n_1B) {
423 mean_1 /= (double) n_1;
424 mean_1A /= (double) n_1A;
425 mean_1B /= (double) n_1B;
426 zone1_ok = 1;
427 }
428 else {
429 mean_1 = mean_1A = mean_1B = 0.0;
430 zone1_ok = 0;
431 if (verbose > 0)
432 fprintf(stderr, "zone 1 unusable\n");
433 }
434
435 if (n_2 && n_2A && n_2B) {
436 mean_2 /= (double) n_2;
437 mean_2A /= (double) n_2A;
438 mean_2B /= (double) n_2B;
439 zone2_ok = 1;
440 }
441 else {
442 mean_2 = mean_2A = mean_2B = 0.0;
443 zone2_ok = 0;
444 if (verbose > 0)
445 fprintf(stderr, "zone 2 unusable\n");
446 }
447
448 if (!skipping && !zone1_ok && !zone2_ok) {
449 // pathological case - can it ever happen?
450 if (verbose > 0)
451 fprintf(stderr, "block skipped\n");
452 continue;
453 }
454
455 if (verbose > 2) {
456 fprintf(stderr, "m_1 = %lf, m_1A = %lf, m_1B = %lf\n", mean_1, mean_1A, mean_1B);
457 fprintf(stderr, "m_2 = %lf, m_2A = %lf, m_2B = %lf\n", mean_2, mean_2A, mean_2B);
458 }
459
460 // calculate new mean values required by embedding rule
461 if (get_signature_bit(n)) {
462 if (zone1_ok) {
463 mean__1A = (mean_1 * (double) (n_1A + n_1B) + (double) n_1B * quality) / (double) (n_1A + n_1B);
464 mean__1B = mean__1A - quality;
465 }
466 if (zone2_ok) {
467 mean__2A = (mean_2 * (double) (n_2A + n_2B) + (double) n_2B * quality) / (double) (n_2A + n_2B);
468 mean__2B = mean__2A - quality;
469 }
470 }
471 else {
472 if (zone1_ok) {
473 mean__1A = (mean_1 * (double) (n_1A + n_1B) - (double) n_1B * quality) / (double) (n_1A + n_1B);
474 mean__1B = mean__1A + quality;
475 }
476 if (zone2_ok) {
477 mean__2A = (mean_2 * (double) (n_2A + n_2B) - (double) n_2B * quality) / (double) (n_2A + n_2B);
478 mean__2B = mean__2A + quality;
479 }
480 }
481
482 // calculate luminance variations
483 if (zone1_ok) {
484 var_1A = rint(mean__1A - mean_1A);
485 var_1B = rint(mean__1B - mean_1B);
486 }
487 else var_1A = var_1B = 0;
488
489 if (zone2_ok) {
490 var_2A = rint(mean__2A - mean_2A);
491 var_2B = rint(mean__2B - mean_2B);
492 }
493 else var_2A = var_2B = 0;
494
495 if (verbose > 2) {
496 if (zone1_ok)
497 fprintf(stderr, "m*_1A = %lf, m*_1B = %lf\n", mean__1A, mean__1B);
498 if (zone2_ok)
499 fprintf(stderr, "m*_2A = %lf, m*_2B = %lf\n", mean__2A, mean__2B);
500 fprintf(stderr, "var %d %d %d %d\n", var_1A, var_1B, var_2A, var_2B);
501 }
502
503 // apply luminance variations to image pixels
504 for (i = 0; i < blocksize; i++)
505 for (j = 0; j < blocksize; j++) {
506 int pixel = image[yb * blocksize + j][xb * blocksize + i];
507 int pixel_zone = zone[j][i];
508 int pixel_category = CATEGORY_VOID;
509 if (pixel_zone == ZONE_1)
510 pixel_category = category1[j][i];
511 else if (pixel_zone == ZONE_2)
512 pixel_category = category2[j][i];
513
514 switch (pixel_zone | pixel_category) {
515 case CLASSIFICATION_1A:
516 pixel = GRAYRANGE(pixel + var_1A);
517 break;
518 case CLASSIFICATION_1B:
519 pixel = GRAYRANGE(pixel + var_1B);
520 break;
521 case CLASSIFICATION_2A:
522 pixel = GRAYRANGE(pixel + var_2A);
523 break;
524 case CLASSIFICATION_2B:
525 pixel = GRAYRANGE(pixel + var_2B);
526 break;
527 }
528 image[yb * blocksize + j][xb * blocksize + i] = pixel;
529 }
530
531 n++;
532 }
533
534 free_grays(category2);
535 free_grays(category1);
536 free_grays(zone);
537 free_grays(block);
538
539 // write output image dimensions to output file
540 pgm_writepgminit(out, cols, rows, maxval, 0);
541
542 // write output image
543 for (row = 0; row < rows; row++)
544 pgm_writepgmrow(out, image[row], cols, maxval, 0);
545
546 fclose(out);
547
548 pgm_freearray(image, rows);
549
550 exit(0);
551 }

Repositories maintained by Peter Meerwald, pmeerw@pmeerw.net.