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comparison Meerwald-dir/wm_koch_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_koch_d.c@4987db85cfae
children
comparison
equal deleted inserted replaced
23:71dd4b96221b 24:9f20bce6184e
1 #include "wm.h"
2 #include "dct.h"
3 #include "signature.h"
4 #include "coord.h"
5 #include "netpbm/pgm.h"
6
7 char *progname;
8
9 void usage(void) {
10 fprintf(stderr, "usage: %s [-h] [-l n] [-o file] [-q n] [-v n] -s file file\n\n", progname);
11 fprintf(stderr, "\t-h\t\tprint usage\n");
12 fprintf(stderr, "\t-l n\t\tsignature robustness factor\n");
13 fprintf(stderr, "\t-o file\t\textracted signature file\n");
14 fprintf(stderr, "\t-q n\t\tquantization (JPEG quality) factor\n");
15 fprintf(stderr, "\t-s file\t\toriginal signature file\n");
16 fprintf(stderr, "\t-v n\t\tverbosity level\n");
17 exit(0);
18 }
19
20 int main(int argc, char *argv[]) {
21
22 FILE *in = stdin;
23 FILE *out = stdout;
24 FILE *sig = NULL;
25
26 gray **image;
27 struct coords *coords;
28
29 char signature_name[MAXPATHLEN];
30 char input_name[MAXPATHLEN] = "(stdin)";
31 char output_name[MAXPATHLEN] = "(stdout)";
32
33 int c;
34 int n;
35
36 int rows, cols, format;
37 gray maxval;
38 int row;
39
40 int seed;
41 int verbose = 0;
42
43 double quality = 0.0;
44 int quantization = 0;
45
46 double **dcts;
47
48 progname = argv[0];
49
50 pgm_init(&argc, argv); wm_init();
51
52 while ((c = getopt(argc, argv, "h?i:l:o:q:s:v:")) != EOF) {
53 switch (c) {
54 case 'h':
55 case '?':
56 usage();
57 break;
58 case 'l':
59 quality = atof(optarg);
60 if (quality <= 0.0) {
61 fprintf(stderr, "%s: signature strength factor %f out of range\n", progname, quality);
62 exit(1);
63 }
64 break;
65 case 'o':
66 if ((out = fopen(optarg, "wb")) == NULL) {
67 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg);
68 exit(1);
69 }
70 strcpy(output_name, optarg);
71 break;
72 case 'q':
73 quantization = atoi(optarg);
74 if (quantization <= 0 || quantization > 100) {
75 fprintf(stderr, "%s: quantization factor %d out of range\n", progname, quantization);
76 exit(1);
77 }
78 break;
79 case 's':
80 if ((sig = fopen(optarg, "r")) == NULL) {
81 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg);
82 exit(1);
83 }
84 strcpy(signature_name, optarg);
85 break;
86 case 'v':
87 verbose = atoi(optarg);
88 if (verbose < 0) {
89 fprintf(stderr, "%s: verbosity level %d out of range\n", progname, verbose);
90 exit(1);
91 }
92 break;
93 }
94 }
95
96 argc -= optind;
97 argv += optind;
98
99 if (argc > 1) {
100 usage();
101 exit(1);
102 }
103
104 if (argc == 1 && *argv[0] != '-') {
105 if ((in = fopen(argv[0], "rb")) == NULL) {
106 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]);
107 exit(1);
108 }
109 else
110 strcpy(input_name, argv[0]);
111 }
112
113 if (sig) {
114 char line[128];
115 fgets(line, sizeof(line), sig);
116 if (strspn(line, "KCSG") >= 4) {
117 fscanf(sig, "%d\n", &nbit_signature);
118 n_signature = NBITSTOBYTES(nbit_signature);
119 if (quality == 0.0)
120 fscanf(sig, "%lf\n", &quality);
121 else
122 fscanf(sig, "%*f\n");
123 if (quantization == 0)
124 fscanf(sig, "%d\n", &quantization);
125 else
126 fscanf(sig, "%*d\n");
127 fscanf(sig, "%d\n", &seed);
128 srandom(seed);
129 fread(signature, sizeof(char), n_signature, sig);
130 init_signature_bits();
131 fscanf(sig, "\n");
132 }
133 else {
134 fprintf(stderr, "%s: invalid signature file %s\n", progname, signature_name);
135 exit(1);
136 }
137 fclose(sig);
138 }
139 else {
140 fprintf(stderr, "%s: signature file not specified, use -s file option\n", progname);
141 exit(1);
142 }
143
144 pgm_readpgminit(in, &cols, &rows, &maxval, &format);
145
146 if (cols % NJPEG) {
147 fprintf(stderr, "%s: image width %d not a multiple of %d\n", progname, cols, NJPEG);
148 exit(1);
149 }
150
151 if (rows % NJPEG) {
152 fprintf(stderr, "%s: image height %d not a multiple of %d\n", progname, rows, NJPEG);
153 exit(1);
154 }
155
156 if ((rows * cols) / (NJPEG * NJPEG) < nbit_signature) {
157 fprintf(stderr, "%s: image too small to extract %d bits of signature\n", progname, nbit_signature);
158 exit(1);
159 }
160
161 init_dct_8x8();
162 init_quantum_JPEG_lumin(quantization);
163
164 dcts = alloc_coeffs_8x8();
165
166 if ((coords = alloc_coords(nbit_signature)) == NULL) {
167 fprintf(stderr, "%s: unable to allocate memory\n", progname);
168 exit(1);
169 }
170
171 image = pgm_allocarray(cols, rows);
172
173 for (row = 0; row < rows; row++)
174 pgm_readpgmrow(in, image[row], cols, maxval, format);
175
176 fclose(in);
177
178 n = 0;
179 while (n < nbit_signature) {
180 int xb;
181 int yb;
182 int c1, c2;
183 double v1, v2;
184
185 do {
186 xb = random() % (cols / NJPEG);
187 yb = random() % (rows / NJPEG);
188 } while (add_coord(coords, xb, yb) < 0);
189
190 fdct_block_8x8(image, xb * NJPEG, yb * NJPEG, dcts);
191
192 do {
193 c1 = (random() % (NJPEG * NJPEG - 2)) + 1;
194 c2 = (random() % (NJPEG * NJPEG - 2)) + 1;
195 } while (c1 == c2 || !is_middle_frequency_coeff_8x8(c1) || !is_middle_frequency_coeff_8x8(c2));
196
197 quantize_8x8(dcts);
198
199 if (verbose >= 1)
200 fprintf(stderr, "%d: quantized DCT block (x %d/y %d), extracting (x %d/y %d), (x %d/y %d) ", n, xb * NJPEG, yb * NJPEG, c1 % NJPEG, c1 / NJPEG, c2 % NJPEG, c2 / NJPEG);
201
202 v1 = dcts[c1 / NJPEG][c1 % NJPEG];
203 v2 = dcts[c2 / NJPEG][c2 % NJPEG];
204
205 if (fabs(v1) > fabs(v2)) {
206 set_signature_bit(n, 1);
207 if (verbose >= 1)
208 fprintf(stderr, "HIGH\n");
209 }
210 else {
211 set_signature_bit(n, 0);
212 if (verbose >= 1)
213 fprintf(stderr, "LOW\n");
214 }
215
216 if (verbose >= 2)
217 print_coeffs_8x8(dcts);
218
219 n++;
220 }
221
222 fprintf(out, "KCWM\n");
223 fprintf(out, "%d\n", nbit_signature);
224 fwrite(signature, sizeof(char), n_signature, out);
225 fprintf(out, "\n");
226
227 fclose(out);
228
229 free_coeffs(dcts);
230
231 pbm_freearray(image, rows);
232
233 exit(0);
234 }

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