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comparison Meerwald-dir/wm_xie2_d.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_xie2_d.c@4987db85cfae
children
comparison
equal deleted inserted replaced
23:71dd4b96221b 24:9f20bce6184e
1 #include "wm.h"
2 #include "signature.h"
3 #include "dwt.h"
4 #include "netpbm/pgm.h"
5
6 char *progname;
7
8 // inverse watermarking transformation, extract embedded bit, check quantization boundaries
9 double wm_transform(int quant, double f1, double f2, double f3) {
10 double s = (fabs(f3) - fabs(f1)) / (double) quant;
11 double l = f1;
12 int x;
13
14 x = 0;
15 while (l < f2) {
16 l += s;
17 x++;
18 }
19
20 if (fabs(l - s - f2) < fabs(l-f2))
21 return (x+1) % 2;
22 else
23 return (x) % 2;
24 }
25
26 void usage(void) {
27 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);
28 fprintf(stderr, "\t-a n\t\tembedding strength (default 0.05)\n");
29 fprintf(stderr, "\t-e n\t\twavelet filtering method\n");
30 fprintf(stderr, "\t-f n\t\tfilter number\n");
31 fprintf(stderr, "\t-F file\t\tfilter definition file\n");
32 fprintf(stderr, "\t-l n\t\tembedding level\n");
33 fprintf(stderr, "\t-h\t\tprint usage\n");
34 fprintf(stderr, "\t-o file\t\textracted signature file\n");
35 fprintf(stderr, "\t-q n\t\tquantization level\n");
36 fprintf(stderr, "\t-s file\t\tsignature to embed in input image\n");
37 fprintf(stderr, "\t-v n\t\tverbosity level\n");
38 exit(0);
39 }
40
41 int main(int argc, char *argv[]) {
42
43 FILE *in = stdin;
44 FILE *out = stdout;
45 FILE *sig = NULL;
46
47 char output_name[MAXPATHLEN] = "(stdout)";
48 char input_name[MAXPATHLEN] = "(stdin)";
49 char signature_name[MAXPATHLEN];
50
51 int c, n;
52 int row, col;
53
54 double alpha = 0.0;
55 int quant = 0;
56 int filter = 0;
57 int method = -1;
58 int level = 0;
59 char filter_name[MAXPATHLEN] = "";
60
61 int seed;
62 int verbose = 0;
63
64 gray **image;
65 Image_tree dwts, p;
66
67 gray maxval;
68 int rows, cols, format;
69
70 progname = argv[0];
71
72 pgm_init(&argc, argv); wm_init2();
73
74 while ((c = getopt(argc, argv, "a:e:f:F:h?l:o:s:v:q:")) != EOF) {
75 switch (c) {
76 case 'e':
77 method = atoi(optarg);
78 if (method < 0) {
79 fprintf(stderr, "%s: wavelet filtering method %d out of range\n", progname, method);
80 exit(1);
81 }
82 break;
83 case 'f':
84 filter = atoi(optarg);
85 if (filter <= 0) {
86 fprintf(stderr, "%s: filter number %d out of range\n", progname, filter);
87 exit(1);
88 }
89 break;
90 case 'F':
91 strcpy(filter_name, optarg);
92 break;
93 case 'h':
94 case '?':
95 usage();
96 break;
97 case 'l':
98 level = atoi(optarg);
99 if (level < 1) {
100 fprintf(stderr, "%s: embedding level out of range\n", progname);
101 exit(1);
102 }
103 break;
104 case 'o':
105 if ((out = fopen(optarg, "wb")) == NULL) {
106 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg);
107 exit(1);
108 }
109 strcpy(output_name, optarg);
110 break;
111 case 'q':
112 quant = atoi(optarg);
113 break;
114 case 'a':
115 alpha = atof(optarg);
116 if (alpha <= 0.0) {
117 fprintf(stderr, "%s: embedding strength factor %f out of range\n", progname, alpha);
118 exit(1);
119 }
120 break;
121 case 's':
122 if ((sig = fopen(optarg, "r")) == NULL) {
123 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg);
124 exit(1);
125 }
126 strcpy(signature_name, optarg);
127 break;
128 case 'v':
129 verbose = atoi(optarg);
130 if (verbose < 0) {
131 fprintf(stderr, "%s: verbosity level %d out of range\n", progname, verbose);
132 exit(1);
133 }
134 break;
135 }
136 }
137
138 argc -= optind;
139 argv += optind;
140
141 if (argc > 1) {
142 usage();
143 exit(1);
144 }
145
146 if (argc == 1 && *argv[0] != '-') {
147 if ((in = fopen(argv[0], "rb")) == NULL) {
148 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]);
149 exit(1);
150 }
151 else
152 strcpy(input_name, argv[0]);
153 }
154
155 if (sig) {
156 char line[32];
157 fgets(line, sizeof(line), sig);
158 if (strspn(line, "XE2SG") >= 5) {
159 fscanf(sig, "%d\n", &nbit_signature);
160 if (alpha == 0.0)
161 fscanf(sig, "%lf\n", &alpha);
162 else
163 fscanf(sig, "%*f\n");
164 if (method < 0)
165 fscanf(sig, "%d\n", &method);
166 else
167 fscanf(sig, "%*d\n");
168 if (filter == 0)
169 fscanf(sig, "%d\n", &filter);
170 else
171 fscanf(sig, "%*d\n");
172 if (!strcmp(filter_name, ""))
173 fscanf(sig, "%[^\n\r]\n", filter_name);
174 else
175 fscanf(sig, "%*[^\n\r]\n");
176 if (quant == 0)
177 fscanf(sig, "%d\n", &quant);
178 else
179 fscanf(sig, "%*d\n");
180 if (level == 0)
181 fscanf(sig, "%d\n", &level);
182 else
183 fscanf(sig, "%*d\n");
184 fscanf(sig, "%d\n", &seed);
185 srandom(seed);
186 n_signature = NBITSTOBYTES(nbit_signature);
187 fread(signature, sizeof(char), n_signature, sig);
188 fscanf(sig, "\n");
189 }
190 else {
191 fprintf(stderr, "%s: invalid signature file %s\n", progname, signature_name);
192 exit(1);
193 }
194 fclose(sig);
195 }
196 else {
197 fprintf(stderr, "%s: signature file not specified, use -s file option\n", progname);
198 exit(1);
199 }
200
201 pgm_readpgminit(in, &cols, &rows, &maxval, &format);
202 if (verbose > 0)
203 fprintf(stderr, "%s: embedding %d bits with strength %d in\n"
204 " %d x %d host image, decomposition level %d\n",
205 progname, nbit_signature, quant, cols, rows, level);
206
207 image = pgm_allocarray(cols, rows);
208 for (row = 0; row < rows; row++)
209 pgm_readpgmrow(in, image[row], cols, maxval, format);
210 fclose(in);
211
212 // decomposition of image
213 init_dwt(cols, rows, filter_name, filter, level, method);
214 #ifdef POLLEN_STUFF
215 #include "pollen_stuff.c"
216 #endif
217 #ifdef PARAM_STUFF
218 #include "param_stuff.c"
219 #endif
220
221 dwts = fdwt(image);
222
223 p = dwts;
224
225 // consider each resolution level
226 while (p->level < level)
227 // descend one level
228 p = p->coarse;
229
230 // repeat binary watermark by sliding a 3-pixel window of approximation image
231 n = 0;
232 for (row = 0; row < p->image->height; row++) {
233 col = 0;
234 while (col < p->image->width - 3) {
235 double b1, b2, b3;
236 double *f1 = &b1, *f2 = &b2, *f3 = &b3;
237
238 // get all three approximation pixels in window
239 b1 = get_pixel(p->image, col + 0, row);
240 b2 = get_pixel(p->image, col + 1, row);
241 b3 = get_pixel(p->image, col + 2, row);
242
243 // bring selected pixels in ascending order
244 #define SWAP(A, B) {double *t = A; A = B; B = t;}
245 if (*f1 > *f2) SWAP(f1, f2);
246 if (*f2 > *f3) SWAP(f2, f3);
247 if (*f1 > *f2) SWAP(f1, f2);
248
249 set_signature_bit(n, wm_transform(quant, *f1, *f2, *f3));
250
251 if (verbose > 1)
252 fprintf(stderr, "%s: extracting #%d (= %d) at (%d/%d); %f < %f < %f\n",
253 progname, n, get_signature_bit(n % nbit_signature), col, row, *f1, *f2, *f3);
254
255 n++;
256 col += 3;
257 col += (2.0 / alpha);
258 }
259 }
260
261 fprintf(out, "XE2WM\n");
262 fprintf(out, "%d\n", n);
263 fwrite(signature, sizeof(char), NBITSTOBYTES(n), out);
264 fprintf(out, "\n");
265 fclose(out);
266
267 pgm_freearray(image, rows);
268
269 exit(0);
270 }

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