Mercurial > hg > wm

comparison Meerwald/wm_xie2_e.c @ 3:acb6967ee76d

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
update to 0.5
author Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date Tue, 14 Aug 2007 21:11:21 +0200
parents
children f83ef905a63d
comparison
equal deleted inserted replaced
2:b92f06d9a967 3:acb6967ee76d
1 #include "wm.h"
2 #include "signature.h"
3 #include "dwt.h"
4 #include "pgm.h"
5
6 char *progname;
7
8 // watermarking transformation, set median pixel to quantization boundary
9 double wm_transform(int quant, double f1, double f2, double f3, int x) {
10 double s = (fabs(f3) - fabs(f1)) / (double) quant;
11 double l = x ? (f1 + s) : f1;
12 double f2new;
13
14 while ((l + 2 * s) < f2) l += 2 * s;
15 f2new = ((f2 - l) < (l + 2 * s - f2)) ? l : (l + 2 * s);
16
17 return f2new;
18 }
19
20 void usage(void) {
21 fprintf(stderr, "usage: %s [-a n] [-e n] [-f n] [-F n] [-h] [-l n] [-o file] [-v n] -s file file\n\n", progname);
22 fprintf(stderr, "\t-a n\t\tembedding strength (default 0.05)\n");
23 fprintf(stderr, "\t-e n\t\twavelet filtering method\n");
24 fprintf(stderr, "\t-f n\t\tfilter number\n");
25 fprintf(stderr, "\t-F file\t\tfilter definition file\n");
26 fprintf(stderr, "\t-l n\t\tembedding level\n");
27 fprintf(stderr, "\t-h\t\tprint usage\n");
28 fprintf(stderr, "\t-o file\t\toutput (watermarked) file\n");
29 fprintf(stderr, "\t-q n\t\tquantization level\n");
30 fprintf(stderr, "\t-s file\t\tsignature to embed in input image\n");
31 fprintf(stderr, "\t-v n\t\tverbosity level\n");
32 exit(0);
33 }
34
35 int main(int argc, char *argv[]) {
36
37 FILE *in = stdin;
38 FILE *out = stdout;
39 FILE *sig = NULL;
40
41 char output_name[MAXPATHLEN] = "(stdout)";
42 char input_name[MAXPATHLEN] = "(stdin)";
43 char signature_name[MAXPATHLEN];
44
45 int c, n;
46 int row, col;
47
48 double alpha = 0.0;
49 int filter = 0;
50 int method = -1;
51 int level = 0;
52 int quant = 0;
53 char filter_name[MAXPATHLEN] = "";
54
55 int seed;
56 int verbose = 0;
57
58 gray **image;
59 Image_tree dwts, p;
60
61 gray maxval;
62 int rows, cols, colors, format;
63
64 progname = argv[0];
65
66 pgm_init(&argc, argv); wm_init();
67
68 while ((c = getopt(argc, argv, "a:e:f:F:h?l:o:s:v:")) != EOF) {
69 switch (c) {
70 case 'e':
71 method = atoi(optarg);
72 if (method < 0) {
73 fprintf(stderr, "%s: wavelet filtering method %d out of range\n", progname, method);
74 exit(1);
75 }
76 break;
77 case 'f':
78 filter = atoi(optarg);
79 if (filter <= 0) {
80 fprintf(stderr, "%s: filter number %d out of range\n", progname, filter);
81 exit(1);
82 }
83 break;
84 case 'F':
85 strcpy(filter_name, optarg);
86 break;
87 case 'h':
88 case '?':
89 usage();
90 break;
91 case 'l':
92 level = atoi(optarg);
93 if (level < 1) {
94 fprintf(stderr, "%s: embedding level out of range\n", progname);
95 exit(1);
96 }
97 break;
98 case 'o':
99 if ((out = fopen(optarg, "wb")) == NULL) {
100 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg);
101 exit(1);
102 }
103 strcpy(output_name, optarg);
104 break;
105 case 'q':
106 quant = atoi(optarg);
107 break;
108 case 'a':
109 alpha = atof(optarg);
110 if (alpha <= 0.0) {
111 fprintf(stderr, "%s: embedding strength factor %f out of range\n", progname, alpha);
112 exit(1);
113 }
114 break;
115 case 's':
116 if ((sig = fopen(optarg, "r")) == NULL) {
117 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg);
118 exit(1);
119 }
120 strcpy(signature_name, optarg);
121 break;
122 case 'v':
123 verbose = atoi(optarg);
124 if (verbose < 0) {
125 fprintf(stderr, "%s: verbosity level %d out of range\n", progname, verbose);
126 exit(1);
127 }
128 break;
129 }
130 }
131
132 argc -= optind;
133 argv += optind;
134
135 if (argc > 1) {
136 usage();
137 exit(1);
138 }
139
140 if (argc == 1 && *argv[0] != '-')
141 if ((in = fopen(argv[0], "rb")) == NULL) {
142 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]);
143 exit(1);
144 }
145 else
146 strcpy(input_name, argv[0]);
147
148 if (sig) {
149 char line[32];
150 fgets(line, sizeof(line), sig);
151 if (strspn(line, "XE2SG") >= 5) {
152 fscanf(sig, "%d\n", &nbit_signature);
153 if (alpha == 0.0)
154 fscanf(sig, "%lf\n", &alpha);
155 else
156 fscanf(sig, "%*lf\n");
157 if (method < 0)
158 fscanf(sig, "%d\n", &method);
159 else
160 fscanf(sig, "%*d\n");
161 if (filter == 0)
162 fscanf(sig, "%d\n", &filter);
163 else
164 fscanf(sig, "%*d\n");
165 if (!strcmp(filter_name, ""))
166 fscanf(sig, "%[^\n\r]\n", &filter_name);
167 else
168 fscanf(sig, "%*[^\n\r]\n");
169 if (quant == 0)
170 fscanf(sig, "%d\n", &quant);
171 else
172 fscanf(sig, "%*d\n");
173 if (level == 0)
174 fscanf(sig, "%d\n", &level);
175 else
176 fscanf(sig, "%*d\n");
177 fscanf(sig, "%d\n", &seed);
178 srandom(seed);
179 n_signature = NBITSTOBYTES(nbit_signature);
180 fread(signature, sizeof(char), n_signature, sig);
181 fscanf(sig, "\n");
182 }
183 else {
184 fprintf(stderr, "%s: invalid signature file %s\n", progname, signature_name);
185 exit(1);
186 }
187 fclose(sig);
188 }
189 else {
190 fprintf(stderr, "%s: signature file not specified, use -s file option\n", progname);
191 exit(1);
192 }
193
194 pgm_readpgminit(in, &cols, &rows, &maxval, &format);
195
196 if (verbose > 0)
197 fprintf(stderr, "%s: embedding %d bits with strength %d in\n"
198 " %d x %d host image, decomposition level %d\n",
199 progname, nbit_signature, quant, cols, rows, level);
200
201 image = pgm_allocarray(cols, rows);
202
203 for (row = 0; row < rows; row++)
204 pgm_readpgmrow(in, image[row], cols, maxval, format);
205
206 fclose(in);
207
208 // decomposition of image
209 init_dwt(cols, rows, filter_name, filter, level, method);
210 #ifdef POLLEN_STUFF
211 #include "pollen_stuff.c"
212 #endif
213 #ifdef PARAM_STUFF
214 #include "param_stuff.c"
215 #endif
216
217 dwts = fdwt(image);
218
219 p = dwts;
220
221 // consider each resolution level
222 while (p->level < level)
223 // descend one level
224 p = p->coarse;
225
226 // repeat binary watermark by sliding a 3-pixel window of approximation image
227 n = 0;
228 for (row = 0; row < p->image->height; row++) {
229 col = 0;
230 while (col < p->image->width - 3) {
231 double MIN_DIFF = (20.0 * alpha);
232 double b1, b2, b3;
233 double *f1 = &b1, *f2 = &b2, *f3 = &b3;
234 double f2new;
235
236 // get all three approximation pixels in window
237 b1 = get_pixel(p->image, col + 0, row);
238 b2 = get_pixel(p->image, col + 1, row);
239 b3 = get_pixel(p->image, col + 2, row);
240
241 // bring selected pixels in ascending order
242 #define SWAP(A, B) {double *t = A; A = B; B = t;}
243 if (*f1 > *f2) SWAP(f1, f2);
244 if (*f2 > *f3) SWAP(f2, f3);
245 if (*f1 > *f2) SWAP(f1, f2);
246
247 if ((*f3 - *f1) < MIN_DIFF) {
248 double adj = (MIN_DIFF - (*f3 - *f1)) / 2.0;
249 *f1 -= adj;
250 *f3 += adj;
251 }
252
253 // apply watermarking transformation (modify median pixel)
254 f2new = wm_transform(quant, *f1, *f2, *f3, get_signature_bit(n % nbit_signature));
255
256 if (verbose > 1)
257 fprintf(stderr, "%s: embedding #%d (= %d) at (%d/%d); %f < %f -> %f < %f\n",
258 progname, n, get_signature_bit(n % nbit_signature), col, row, *f1, *f2, f2new, *f3);
259
260 *f2 = f2new;
261
262 // write modified pixel
263 set_pixel(p->image, col + 0, row, b1);
264 set_pixel(p->image, col + 1, row, b2);
265 set_pixel(p->image, col + 2, row, b3);
266 n++;
267 col += 3;
268 col+= (2.0 / alpha);
269 }
270 }
271
272
273 // skip over some pixels
274
275 idwt(dwts, image);
276
277 pgm_writepgminit(out, cols, rows, maxval, 0);
278
279 for (row = 0; row < rows; row++)
280 pgm_writepgmrow(out, image[row], cols, maxval, 0);
281
282 fclose(out);
283
284 pgm_freearray(image, rows);
285
286 exit(0);
287 }

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