Mercurial > hg > wm
comparison Meerwald/cmp_wang_sig.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
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| -1:000000000000 | 0:be303a3f5ea8 |
|---|---|
| 1 #include "wm.h" | |
| 2 | |
| 3 char *progname; | |
| 4 | |
| 5 void usage(void) { | |
| 6 fprintf(stderr, "usage: %s [-h] [-C] [-o file] [-v n] -s file file\n\n", progname); | |
| 7 fprintf(stderr, "\t-C\t\toutput correlation only\n"); | |
| 8 fprintf(stderr, "\t-h\t\tprint usage\n"); | |
| 9 fprintf(stderr, "\t-o file\t\toutput file\n"); | |
| 10 fprintf(stderr, "\t-v n\t\tverbosity level\n"); | |
| 11 fprintf(stderr, "\t-s file\t\toriginal signature file\n"); | |
| 12 exit(0); | |
| 13 } | |
| 14 | |
| 15 int main(int argc, char *argv[]) { | |
| 16 | |
| 17 FILE *in = stdin; | |
| 18 FILE *out = stdout; | |
| 19 FILE *sig = NULL; | |
| 20 | |
| 21 char signature_name[MAXPATHLEN]; | |
| 22 char output_name[MAXPATHLEN] = "(stdout)"; | |
| 23 char input_name[MAXPATHLEN] = "(stdin)"; | |
| 24 | |
| 25 int c; | |
| 26 int sig_n, in_n; | |
| 27 double sig_a, sig_b; | |
| 28 int sig_e, sig_f; | |
| 29 double s1, s2, s3; | |
| 30 char line[32]; | |
| 31 | |
| 32 int verbose = 0; | |
| 33 int correlation_only = 0; | |
| 34 | |
| 35 progname = argv[0]; | |
| 36 | |
| 37 while ((c = getopt(argc, argv, "h?Co:s:v:")) != EOF) { | |
| 38 switch (c) { | |
| 39 case 'h': | |
| 40 case '?': | |
| 41 usage(); | |
| 42 break; | |
| 43 case 'C': | |
| 44 correlation_only = 1; | |
| 45 break; | |
| 46 case 'o': | |
| 47 if ((out = fopen(optarg, "w")) == NULL) { | |
| 48 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg); | |
| 49 exit(1); | |
| 50 } | |
| 51 strcpy(output_name, optarg); | |
| 52 break; | |
| 53 case 's': | |
| 54 if ((sig = fopen(optarg, "r")) == NULL) { | |
| 55 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg); | |
| 56 exit(1); | |
| 57 } | |
| 58 strcpy(signature_name, optarg); | |
| 59 break; | |
| 60 case 'v': | |
| 61 verbose = atoi(optarg); | |
| 62 if (verbose < 0) { | |
| 63 fprintf(stderr, "%s: verbosity level %d out of range\n", progname, verbose); | |
| 64 exit(1); | |
| 65 } | |
| 66 break; | |
| 67 } | |
| 68 } | |
| 69 | |
| 70 argc -= optind; | |
| 71 argv += optind; | |
| 72 | |
| 73 if (argc > 1) { | |
| 74 usage(); | |
| 75 exit(1); | |
| 76 } | |
| 77 | |
| 78 if (argc == 1 && *argv[0] != '-') | |
| 79 if ((in = fopen(argv[0], "r")) == NULL) { | |
| 80 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]); | |
| 81 exit(1); | |
| 82 } | |
| 83 else | |
| 84 strcpy(input_name, argv[0]); | |
| 85 | |
| 86 if (!sig) { | |
| 87 fprintf(stderr, "%s: original signature file not specified, use -s file option\n", progname); | |
| 88 exit(1); | |
| 89 } | |
| 90 | |
| 91 fgets(line, sizeof(line), sig); | |
| 92 if (strspn(line, "WGSG") < 4) { | |
| 93 fprintf(stderr, "%s: original signature file %s invalid\n", progname, signature_name); | |
| 94 exit(1); | |
| 95 } | |
| 96 | |
| 97 fgets(line, sizeof(line), in); | |
| 98 if (strspn(line, "WGWM") < 4) { | |
| 99 fprintf(stderr, "%s: watermark file %s invalid\n", progname, input_name); | |
| 100 exit(1); | |
| 101 } | |
| 102 | |
| 103 fscanf(sig, "%d\n", &sig_n); | |
| 104 fscanf(in, "%d\n", &in_n); | |
| 105 if (sig_n != in_n) { | |
| 106 fprintf(stderr, "%s: watermark length mismatch (original %d, input %d)\n", progname, sig_n, in_n); | |
| 107 exit(1); | |
| 108 } | |
| 109 if (sig_n <= 0 || sig_n > 32000) { | |
| 110 fprintf(stderr, "%s: invalid original watermark length %d\n", progname, sig_n); | |
| 111 exit(1); | |
| 112 } | |
| 113 if (in_n != sig_n) { | |
| 114 fprintf(stderr, "%s: invalid watermark length %d, does not match signature length\n", progname, in_n); | |
| 115 exit(1); | |
| 116 } | |
| 117 | |
| 118 fscanf(sig, "%lf\n", &sig_a); | |
| 119 fscanf(sig, "%lf\n", &sig_b); | |
| 120 fscanf(sig, "%d\n", &sig_e); | |
| 121 fscanf(sig, "%d\n", &sig_f); | |
| 122 fscanf(sig, "%*[^\n\r]\n"); | |
| 123 | |
| 124 /* | |
| 125 * normalized correlation | |
| 126 * Craver, S., "Can Invisible Watermarks Resolve Rightful Ownership?", IBM Research Report, 1996, p. 5 | |
| 127 */ | |
| 128 | |
| 129 s1 = s2 = s3 = 0.0; | |
| 130 while (in_n > 0) { | |
| 131 double sig_x, in_x; | |
| 132 | |
| 133 fscanf(sig, "%lf\n", &sig_x); | |
| 134 fscanf(in, "%lf\n", &in_x); | |
| 135 | |
| 136 if (verbose >= 1) { | |
| 137 fprintf(stderr, "orig %f input %f\n", sig_x, in_x); | |
| 138 } | |
| 139 | |
| 140 s1 += sig_x * in_x; | |
| 141 s2 += in_x * in_x; | |
| 142 s3 += sig_x * sig_x; | |
| 143 | |
| 144 in_n--; | |
| 145 } | |
| 146 | |
| 147 fprintf(out, "%f\n", s1 / sqrt(s2 * s3)); | |
| 148 | |
| 149 fclose(sig); | |
| 150 fclose(out); | |
| 151 fclose(in); | |
| 152 | |
| 153 exit(0); | |
| 154 } |