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comparison Meerwald-dir/wm_bruyn_e.c @ 24:9f20bce6184e v0.7

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move directories, support netpbm 11
author Peter Meerwald-Stadler <pmeerw@pmeerw.net>
date Fri, 20 Dec 2024 13:08:59 +0100
parents Meerwald/wm_bruyn_e.c@bd669312f068
children
comparison
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23:71dd4b96221b 24:9f20bce6184e
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 "netpbm/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, format;
41 int c;
42 int i, j;
43 int n;
44 int row;
45 int n_block;
46 int skipping = 0;
47
48 char signature_name[MAXPATHLEN];
49 char input_name[MAXPATHLEN] = "(stdin)";
50 char output_name[MAXPATHLEN] = "(stdout)";
51
52 double quality = 0.0;
53 double threshold_noise = 0.0;
54 double threshold_slope = 0.0;
55 int pattern1 = 0;
56 int pattern2 = 0;
57 int blocksize = 0;
58 int seed;
59
60 int verbose = 0;
61
62 struct coords *coords;
63
64 progname = argv[0];
65
66 pgm_init(&argc, argv); wm_init();
67
68 // parse command line and set options
69 while ((c = getopt(argc, argv, "b:h?n:o:p:P:q:s:t:T:v:k")) != EOF) {
70 switch (c) {
71 case 'k':
72 skipping = 1;
73 break;
74 case 'h':
75 case '?':
76 usage();
77 break;
78 case 'n':
79 nbit_signature = atoi(optarg);
80 if (nbit_signature <= 0 || nbit_signature > NBITSIGNATURE) {
81 fprintf(stderr, "%s: invalid signature length %d\n", progname, nbit_signature);
82 exit(1);
83 }
84 break;
85 case 'o':
86 if ((out = fopen(optarg, "wb")) == NULL) {
87 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg);
88 exit(1);
89 }
90 strcpy(output_name, optarg);
91 break;
92 case 'p':
93 pattern1 = atoi(optarg);
94 if (pattern1 <= 0 || pattern1 > NPATTERN) {
95 fprintf(stderr, "%s: pattern type out of range\n", progname);
96 exit(1);
97 }
98 break;
99 case 'P':
100 pattern2 = atoi(optarg);
101 if (pattern2 <= 0 || pattern2 > 3) {
102 fprintf(stderr, "%s: pattern type out of range\n", progname);
103 exit(1);
104 }
105 break;
106 case 'q':
107 quality = atof(optarg);
108 if (quality <= 0) {
109 fprintf(stderr, "%s: quality factor %f out of range\n", progname, quality);
110 }
111 break;
112 case 's':
113 if ((sig = fopen(optarg, "r")) == NULL) {
114 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg);
115 exit(1);
116 }
117 strcpy(signature_name, optarg);
118 break;
119 case 't':
120 threshold_noise = atof(optarg);
121 if (threshold_noise <= 0) {
122 fprintf(stderr, "%s: noise threshold %f out of range\n", progname, threshold_noise);
123 }
124 break;
125 case 'T':
126 threshold_slope = atof(optarg);
127 if (threshold_slope <= 0) {
128 fprintf(stderr, "%s: slope threshold %f out of range\n", progname, threshold_slope);
129 }
130 break;
131 case 'v':
132 verbose = atoi(optarg);
133 if (verbose < 0) {
134 fprintf(stderr, "%s: verbosity level %d out of range\n",progname, verbose);
135 exit(1);
136 }
137 break;
138 }
139 }
140
141 argc -= optind;
142 argv += optind;
143
144 if (argc > 1) {
145 usage();
146 exit(1);
147 }
148
149 // open input image file or read from stdin
150 if (argc == 1 && *argv[0] != '-') {
151 if ((in = fopen(argv[0], "rb")) == NULL) {
152 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]);
153 exit(1);
154 }
155 else
156 strcpy(input_name, argv[0]);
157 }
158
159 // read signature file and set options
160 // command line options override signature file options
161 if (sig) {
162 char line[128];
163 fgets(line, sizeof(line), sig);
164 if (strspn(line, "BRSG") >= 4) {
165 if (nbit_signature == 0)
166 fscanf(sig, "%d\n", &nbit_signature);
167 else
168 fscanf(sig, "%*d\n");
169 if (skipping == 0)
170 fscanf(sig, "%d\n", &skipping);
171 else
172 fscanf(sig, "%*d\n");
173 if (pattern1 == 0)
174 fscanf(sig, "%d\n", &pattern1);
175 else
176 fscanf(sig, "%*d\n");
177 if (pattern2 == 0)
178 fscanf(sig, "%d\n", &pattern2);
179 else
180 fscanf(sig, "%*d\n");
181 if (quality == 0.0)
182 fscanf(sig, "%lf\n", &quality);
183 else
184 fscanf(sig, "%*f\n");
185 if (threshold_noise == 0.0)
186 fscanf(sig, "%lf\n", &threshold_noise);
187 else
188 fscanf(sig, "%*f\n");
189 if (threshold_slope == 0.0)
190 fscanf(sig, "%lf\n", &threshold_slope);
191 else
192 fscanf(sig, "%*f\n");
193 if (blocksize == 0)
194 fscanf(sig, "%d\n", &blocksize);
195 else
196 fscanf(sig, "%*d\n");
197 fscanf(sig, "%d\n", &seed);
198 srandom(seed);
199 fread(signature, sizeof(char), NBITSTOBYTES(nbit_signature), sig);
200 fscanf(sig, "\n");
201 }
202 else {
203 fprintf(stderr, "%s: invalid signature file %s\n", progname, signature_name);
204 exit(1);
205 }
206 fclose(sig);
207 }
208 else {
209 fprintf(stderr, "%s: signature file not specified, use -s file option\n", progname);
210 exit(1);
211 }
212
213 if (pattern1 <= 0 || pattern2 <= 0 || pattern1 > NPATTERN || pattern2 > NPATTERN) {
214 fprintf(stderr, "%s: invalid pattern type specified\n", progname);
215 exit(1);
216 }
217
218 // read dimensions of input image file
219 pgm_readpgminit(in, &cols, &rows, &maxval, &format);
220
221 // see if we can embed all signature bits
222 // we want at least half of the blocks untouched
223 if (((rows / blocksize) * (cols / blocksize)) < nbit_signature / 2) {
224 fprintf(stderr, "%s: image not large enough to embed %d bits of signature\n", progname, nbit_signature);
225 exit(1);
226 }
227 n_block = blocksize * blocksize;
228
229 // allocate structure to remember which blocks we already touched,
230 // allow plenty of room to skip over blocks
231 if ((coords = alloc_coords(nbit_signature * 16)) == NULL) {
232 fprintf(stderr, "%s: unable to allocate memory\n", progname);
233 exit(1);
234 }
235
236 // read in input image file
237 image = pgm_allocarray(cols, rows);
238 for (row = 0; row < rows; row++)
239 pgm_readpgmrow(in, image[row], cols, maxval, format);
240
241 fclose(in);
242
243 row = 0;
244
245 // allocate memory for one block
246 block = alloc_grays(blocksize, blocksize);
247
248 // allocate memory for zone classification
249 zone = alloc_grays(blocksize, blocksize);
250
251 // allocate memory for category classification
252 category1 = alloc_grays(blocksize, blocksize);
253 category2 = alloc_grays(blocksize, blocksize);
254
255 // set up category classification array according to
256 // pattern type parameter
257 for (i = 0; i < blocksize; i++)
258 for (j = 0; j < blocksize; j++) {
259 category1[j][i] = lookup_pattern(pattern1, i, j);
260 category2[j][i] = lookup_pattern(pattern2, i, j);
261 }
262
263 // allocate memory for slope calculation
264 slope = malloc(sizeof(double) * n_block);
265
266 // embed all the signature bits, one by one
267 n = 0;
268 while (n < nbit_signature) {
269 int xb;
270 int yb;
271 int blocktype;
272 double smax;
273 int alpha, beta_minus, beta_plus;
274 double mean_1A, mean_1B, mean_2A, mean_2B, mean_1, mean_2;
275 double mean__1A, mean__1B, mean__2A, mean__2B;
276 int n_1A, n_1B, n_2A, n_2B, n_1, n_2;
277 int var_1A, var_1B, var_2A, var_2B;
278 int zone1_ok, zone2_ok;
279
280 // find an unused block randomly, depending on seed
281 do {
282 xb = random() % (cols / blocksize);
283 yb = random() % (rows / blocksize);
284 } while (add_coord(coords, xb, yb) < 0);
285
286 // copy image block
287 copy_grays_to_block(block, image, xb * blocksize, yb * blocksize, blocksize, blocksize);
288
289 if (verbose > 0)
290 fprintf(stderr, "embedding bit #%d (= %d) in block at (%d/%d)\n", n, get_signature_bit(n), xb * blocksize, yb * blocksize);
291 if (verbose > 8) {
292 print_grays(image, xb * blocksize, yb * blocksize, blocksize, blocksize);
293 fprintf(stderr, "\n");
294 }
295
296 // sort luminance values in block to represent increasing function F
297 sort_grays(block[0], n_block);
298
299 if (verbose > 8) {
300 print_grays(block, 0, 0, blocksize, blocksize);
301 fprintf(stderr, "\n");
302 }
303
304 // calculate slopes of F and determine smax, the max. slope of F
305 // the index where smax occures is called alpha
306 alpha = 0;
307 smax = 0.0;
308 for (i = 0; i < n_block - 1; i++) {
309 slope[i] = block[0][i + 1] - block[0][i];
310 if (slope[i] > smax) {
311 smax = slope[i];
312 alpha = i;
313 }
314 }
315 slope[n_block - 1] = 0;
316
317 // block type classification
318 blocktype = BLOCKTYPE_UNKNOWN;
319
320 if (smax < threshold_noise) {
321 // block has noise contrast
322
323 blocktype = BLOCKTYPE_NOISE;
324 beta_minus = beta_plus = alpha;
325 }
326 else {
327 // block has progressive or hard contrast, let's find out...
328
329 beta_minus = alpha - 1;
330 while (beta_minus >= 0 && smax - slope[beta_minus] <= threshold_slope)
331 beta_minus--;
332
333 beta_plus = alpha + 1;
334 while (beta_plus < n_block && smax - slope[beta_plus] <= threshold_slope)
335 beta_plus++;
336
337 if (beta_minus + 1 == alpha && beta_plus - 1 == alpha)
338 blocktype = BLOCKTYPE_HARD;
339 else
340 blocktype = BLOCKTYPE_PROGRESSIVE;
341 }
342
343 if (verbose > 1) {
344 fprintf(stderr, "blocktype: %d\n", blocktype);
345 fprintf(stderr, "Smax = %lf, alpha = %d, beta- = %d, beta+ = %d\n", smax, alpha, beta_minus, beta_plus);
346 }
347
348 // block pixel classification
349 for (i = 0; i < blocksize; i++)
350 for (j = 0; j < blocksize; j++) {
351 gray pixel = image[yb * blocksize + j][xb * blocksize + i];
352 zone[j][i] = ZONE_VOID;
353 switch (blocktype) {
354 case BLOCKTYPE_PROGRESSIVE:
355 case BLOCKTYPE_HARD:
356 if (pixel < block[0][beta_minus])
357 zone[j][i] = ZONE_1;
358 else if (pixel > block[0][beta_plus])
359 zone[j][i] = ZONE_2;
360 break;
361 case BLOCKTYPE_NOISE:
362 if (pixel < block[0][n_block / 2])
363 zone[j][i] = ZONE_1;
364 else if (pixel > block[0][n_block / 2])
365 zone[j][i] = ZONE_2;
366 break;
367 default:
368 fprintf(stderr, "%s: invalid block type\n", progname);
369 break;
370 }
371 }
372
373 if (verbose > 8) {
374 print_grays(zone, 0, 0, blocksize, blocksize);
375 fprintf(stderr, "\n");
376 }
377
378 // calculate mean values for zone/categories
379 mean_1A = mean_1B = mean_2A = mean_2B = mean_1 = mean_2 = 0.0;
380 mean__1A = mean__1B = mean__2A = mean__2B = 0.0;
381 n_1A = n_1B = n_2A = n_2B = n_1 = n_2 = 0;
382 for (i = 0; i < blocksize; i++)
383 for (j = 0; j < blocksize; j++) {
384 gray pixel = image[yb * blocksize + j][xb * blocksize + i];
385 int pixel_zone = zone[j][i];
386 int pixel_category = CATEGORY_VOID;
387 if (pixel_zone == ZONE_1)
388 pixel_category = category1[j][i];
389 else if (pixel_zone == ZONE_2)
390 pixel_category = category2[j][i];
391
392 switch (pixel_zone | pixel_category) {
393 case CLASSIFICATION_1A:
394 n_1++;
395 n_1A++;
396 mean_1A += pixel;
397 mean_1 += pixel;
398 break;
399 case CLASSIFICATION_1B:
400 n_1++;
401 n_1B++;
402 mean_1B += pixel;
403 mean_1 += pixel;
404 break;
405 case CLASSIFICATION_2A:
406 n_2++;
407 n_2A++;
408 mean_2A += pixel;
409 mean_2 += pixel;
410 break;
411 case CLASSIFICATION_2B:
412 n_2++;
413 n_2B++;
414 mean_2B += pixel;
415 mean_2 += pixel;
416 break;
417 }
418 }
419
420 if (n_1 && n_1A && n_1B) {
421 mean_1 /= (double) n_1;
422 mean_1A /= (double) n_1A;
423 mean_1B /= (double) n_1B;
424 zone1_ok = 1;
425 }
426 else {
427 mean_1 = mean_1A = mean_1B = 0.0;
428 zone1_ok = 0;
429 if (verbose > 0)
430 fprintf(stderr, "zone 1 unusable\n");
431 }
432
433 if (n_2 && n_2A && n_2B) {
434 mean_2 /= (double) n_2;
435 mean_2A /= (double) n_2A;
436 mean_2B /= (double) n_2B;
437 zone2_ok = 1;
438 }
439 else {
440 mean_2 = mean_2A = mean_2B = 0.0;
441 zone2_ok = 0;
442 if (verbose > 0)
443 fprintf(stderr, "zone 2 unusable\n");
444 }
445
446 if (!skipping && !zone1_ok && !zone2_ok) {
447 // pathological case - can it ever happen?
448 if (verbose > 0)
449 fprintf(stderr, "block skipped\n");
450 continue;
451 }
452
453 if (verbose > 2) {
454 fprintf(stderr, "m_1 = %lf, m_1A = %lf, m_1B = %lf\n", mean_1, mean_1A, mean_1B);
455 fprintf(stderr, "m_2 = %lf, m_2A = %lf, m_2B = %lf\n", mean_2, mean_2A, mean_2B);
456 }
457
458 // calculate new mean values required by embedding rule
459 if (get_signature_bit(n)) {
460 if (zone1_ok) {
461 mean__1A = (mean_1 * (double) (n_1A + n_1B) + (double) n_1B * quality) / (double) (n_1A + n_1B);
462 mean__1B = mean__1A - quality;
463 }
464 if (zone2_ok) {
465 mean__2A = (mean_2 * (double) (n_2A + n_2B) + (double) n_2B * quality) / (double) (n_2A + n_2B);
466 mean__2B = mean__2A - quality;
467 }
468 }
469 else {
470 if (zone1_ok) {
471 mean__1A = (mean_1 * (double) (n_1A + n_1B) - (double) n_1B * quality) / (double) (n_1A + n_1B);
472 mean__1B = mean__1A + quality;
473 }
474 if (zone2_ok) {
475 mean__2A = (mean_2 * (double) (n_2A + n_2B) - (double) n_2B * quality) / (double) (n_2A + n_2B);
476 mean__2B = mean__2A + quality;
477 }
478 }
479
480 // calculate luminance variations
481 if (zone1_ok) {
482 var_1A = rint(mean__1A - mean_1A);
483 var_1B = rint(mean__1B - mean_1B);
484 }
485 else var_1A = var_1B = 0;
486
487 if (zone2_ok) {
488 var_2A = rint(mean__2A - mean_2A);
489 var_2B = rint(mean__2B - mean_2B);
490 }
491 else var_2A = var_2B = 0;
492
493 if (verbose > 2) {
494 if (zone1_ok)
495 fprintf(stderr, "m*_1A = %lf, m*_1B = %lf\n", mean__1A, mean__1B);
496 if (zone2_ok)
497 fprintf(stderr, "m*_2A = %lf, m*_2B = %lf\n", mean__2A, mean__2B);
498 fprintf(stderr, "var %d %d %d %d\n", var_1A, var_1B, var_2A, var_2B);
499 }
500
501 // apply luminance variations to image pixels
502 for (i = 0; i < blocksize; i++)
503 for (j = 0; j < blocksize; j++) {
504 int pixel = image[yb * blocksize + j][xb * blocksize + i];
505 int pixel_zone = zone[j][i];
506 int pixel_category = CATEGORY_VOID;
507 if (pixel_zone == ZONE_1)
508 pixel_category = category1[j][i];
509 else if (pixel_zone == ZONE_2)
510 pixel_category = category2[j][i];
511
512 switch (pixel_zone | pixel_category) {
513 case CLASSIFICATION_1A:
514 pixel = GRAYRANGE(pixel + var_1A);
515 break;
516 case CLASSIFICATION_1B:
517 pixel = GRAYRANGE(pixel + var_1B);
518 break;
519 case CLASSIFICATION_2A:
520 pixel = GRAYRANGE(pixel + var_2A);
521 break;
522 case CLASSIFICATION_2B:
523 pixel = GRAYRANGE(pixel + var_2B);
524 break;
525 }
526 image[yb * blocksize + j][xb * blocksize + i] = pixel;
527 }
528
529 n++;
530 }
531
532 free_grays(category2);
533 free_grays(category1);
534 free_grays(zone);
535 free_grays(block);
536
537 // write output image dimensions to output file
538 pgm_writepgminit(out, cols, rows, maxval, 0);
539
540 // write output image
541 for (row = 0; row < rows; row++)
542 pgm_writepgmrow(out, image[row], cols, maxval, 0);
543
544 fclose(out);
545
546 pgm_freearray(image, rows);
547
548 exit(0);
549 }

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