Mercurial > hg > wm
comparison Meerwald-dir/cmp_kim_sig.c @ 24:9f20bce6184e v0.7
move directories, support netpbm 11
| author | Peter Meerwald-Stadler <pmeerw@pmeerw.net> |
|---|---|
| date | Fri, 20 Dec 2024 13:08:59 +0100 |
| parents | Meerwald/cmp_kim_sig.c@f83ef905a63d |
| children |
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| 23:71dd4b96221b | 24:9f20bce6184e |
|---|---|
| 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, i; | |
| 26 int in_level; | |
| 27 double *input_watermark, *orig_watermark; | |
| 28 int sig_n, in_n; | |
| 29 double sig_a; | |
| 30 double sig_A; | |
| 31 int sig_l; | |
| 32 int sig_e, sig_f; | |
| 33 double s1, s2, s3; | |
| 34 double correlation; | |
| 35 char line[32]; | |
| 36 | |
| 37 int verbose = 0; | |
| 38 int correlation_only = 0; | |
| 39 | |
| 40 progname = argv[0]; | |
| 41 | |
| 42 while ((c = getopt(argc, argv, "h?Co:s:v:")) != EOF) { | |
| 43 switch (c) { | |
| 44 case 'h': | |
| 45 case '?': | |
| 46 usage(); | |
| 47 break; | |
| 48 case 'C': | |
| 49 correlation_only = 1; | |
| 50 break; | |
| 51 case 'o': | |
| 52 if ((out = fopen(optarg, "w")) == NULL) { | |
| 53 fprintf(stderr, "%s: unable to open output file %s\n", progname, optarg); | |
| 54 exit(1); | |
| 55 } | |
| 56 strcpy(output_name, optarg); | |
| 57 break; | |
| 58 case 's': | |
| 59 if ((sig = fopen(optarg, "r")) == NULL) { | |
| 60 fprintf(stderr, "%s: unable to open signature file %s\n", progname, optarg); | |
| 61 exit(1); | |
| 62 } | |
| 63 strcpy(signature_name, optarg); | |
| 64 break; | |
| 65 case 'v': | |
| 66 verbose = atoi(optarg); | |
| 67 if (verbose < 0) { | |
| 68 fprintf(stderr, "%s: verbosity level %d out of range\n", progname, verbose); | |
| 69 exit(1); | |
| 70 } | |
| 71 break; | |
| 72 } | |
| 73 } | |
| 74 | |
| 75 argc -= optind; | |
| 76 argv += optind; | |
| 77 | |
| 78 if (argc > 1) { | |
| 79 usage(); | |
| 80 exit(1); | |
| 81 } | |
| 82 | |
| 83 if (argc == 1 && *argv[0] != '-') { | |
| 84 if ((in = fopen(argv[0], "r")) == NULL) { | |
| 85 fprintf(stderr, "%s: unable to open input file %s\n", progname, argv[0]); | |
| 86 exit(1); | |
| 87 } | |
| 88 else | |
| 89 strcpy(input_name, argv[0]); | |
| 90 } | |
| 91 | |
| 92 if (!sig) { | |
| 93 fprintf(stderr, "%s: original signature file not specified, use -s file option\n", progname); | |
| 94 exit(1); | |
| 95 } | |
| 96 | |
| 97 fgets(line, sizeof(line), sig); | |
| 98 if (strspn(line, "KISG") < 4) { | |
| 99 fprintf(stderr, "%s: original signature file %s invalid\n", progname, signature_name); | |
| 100 exit(1); | |
| 101 } | |
| 102 | |
| 103 fgets(line, sizeof(line), in); | |
| 104 if (strspn(line, "KIWM") < 4) { | |
| 105 fprintf(stderr, "%s: watermark file %s invalid\n", progname, input_name); | |
| 106 exit(1); | |
| 107 } | |
| 108 | |
| 109 fscanf(sig, "%d\n", &sig_n); | |
| 110 fscanf(in, "%d\n", &in_n); | |
| 111 | |
| 112 if (sig_n <= 0 || sig_n > 32000) { | |
| 113 fprintf(stderr, "%s: invalid original watermark length %d\n", progname, sig_n); | |
| 114 exit(1); | |
| 115 } | |
| 116 | |
| 117 fscanf(sig, "%lf\n", &sig_a); | |
| 118 fscanf(sig, "%lf\n", &sig_A); | |
| 119 fscanf(sig, "%d\n", &sig_l); | |
| 120 fscanf(sig, "%d\n", &sig_e); | |
| 121 fscanf(sig, "%d\n", &sig_f); | |
| 122 fscanf(sig, "%*[^\n\r]\n"); | |
| 123 | |
| 124 orig_watermark = malloc(sig_n * sizeof(double)); | |
| 125 for (i = 0; i < sig_n; i++) | |
| 126 fscanf(sig, "%lf\n", &orig_watermark[i]); | |
| 127 fclose(sig); | |
| 128 | |
| 129 fscanf(in, "%d\n", &in_level); | |
| 130 input_watermark = malloc(in_n * sizeof(double)); | |
| 131 for (i = 0; i < in_n; i++) | |
| 132 fscanf(in, "%lf\n", &input_watermark[i]); | |
| 133 fclose(in); | |
| 134 | |
| 135 /* | |
| 136 * normalized correlation | |
| 137 * Craver, S., "Can Invisible Watermarks Resolve Rightful Ownership?", IBM Research Report, 1996, p. 5 | |
| 138 */ | |
| 139 | |
| 140 s1 = s2 = s3 = 0.0; | |
| 141 for (i = 0; i < in_n; i++) { | |
| 142 double in_x, sig_x; | |
| 143 | |
| 144 in_x = input_watermark[i]; | |
| 145 sig_x = orig_watermark[i % sig_n]; | |
| 146 | |
| 147 s1 += sig_x * in_x; | |
| 148 s2 += in_x * in_x; | |
| 149 s3 += sig_x * sig_x; | |
| 150 } | |
| 151 | |
| 152 correlation = s1 / sqrt(s2 * s3); | |
| 153 | |
| 154 if (!correlation_only) | |
| 155 fprintf(out, "%s: correlation: %f\n", progname, correlation); | |
| 156 else | |
| 157 fprintf(out, "%f\n", correlation); | |
| 158 | |
| 159 fclose(out); | |
| 160 | |
| 161 free(orig_watermark); | |
| 162 free(input_watermark); | |
| 163 | |
| 164 exit(0); | |
| 165 } |