--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Fotopoulos-dir/cast-pv.c	Fri Dec 20 13:08:59 2024 +0100
@@ -0,0 +1,135 @@
+/* Watermarking program - Fast Cosine Transform based	*/
+/* Module	: Casting				*/
+/* Author	: Vassilis Fotopoulos			*/
+/* Date		: 21/7/1999				*/
+/* Revision	: 2.01a					*/
+/* Developed at	: ELLAB                  		*/
+/*                Electronics Laboratory           	*/
+/*                Department of Physics             	*/
+/*                University of Patras - GREECE      	*/
+/*		  Copyleft (c) 1999	    		*/
+/*  		  (without Visual Masking)              */
+/*------------------------------------------------------*/
+/*	pseudorandom noise generator's code is		*/
+/*	taken from "Numerical Recipes in C"		*/
+/*	FCT implementation from the University of Bath	*/
+/*------------------------------------------------------*/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <float.h>
+#include <getopt.h>
+#include "common.h"
+#include "netpbm/pgm.h"
+
+double cu[1024];
+double cv[1024];
+int height, width;
+
+//--------------------------------------------------------
+void add_watermark(double *in, int N, int coeff_start, int wm_length, int wm_key, double wm_alpha)
+{
+  int row, col, count;
+  long int elem, L, M, temp, seed;
+  double a;
+  count = 0;
+  elem = 0;
+  row = 2;
+  col = -1;
+  M = coeff_start;
+  L = wm_length;
+  seed = wm_key;
+  a = wm_alpha;
+  do {
+    do {
+      row--;
+      col++;
+      elem++;
+      if (col < N) {
+        if (elem > M) {
+          temp = row * N + col;
+          in[temp] += a * fabs(in[temp]) * gasdev(&seed);
+          count++;
+        }
+      }
+    } while (row > 0);
+    row = 2 + col;
+    col = -1;
+  } while (count < L);
+}
+//--------------------------------------------------------
+void initialize_constants(void)
+{
+  int i;
+  cu[0] = cv[0] = 0.7071068;
+  for (i = 1; i < 1024; i++)
+    cu[i] = cv[i] = 1.0;
+}
+
+//--------------------------------------------------------
+int main(int argc, char* argv[])
+{
+  FILE *in, *out;
+  int **image_i;
+  double *image_f = NULL;
+  int N;
+  int c;
+  int coeff_start = 5000, wm_length = 10000, wm_key = 123;
+  double wm_alpha = 0.2;
+
+  pgm_init(&argc, argv); wm_init();
+
+  while ((c = getopt(argc, argv, "a:s:l:k:")) != EOF) {
+    switch (c) {
+        case 'a':
+        wm_alpha = atof(optarg);
+        break;
+        case 's':
+        coeff_start = atoi(optarg);
+        break;
+        case 'l':
+        wm_length = atoi(optarg);
+        break;
+        case 'k':
+        wm_key = atoi(optarg);
+        break;
+    }
+  }
+  argc -= optind;
+  argv += optind;
+
+  in = stdin;
+  out = stdout;
+
+  open_image(in, &width, &height);
+  image_i = imatrix(height, width);
+  load_image(image_i, in, width, height);
+
+  if (height == width)
+    N = height;
+  else {
+    fprintf(stderr, "Cannot Proccess non-square images!\n");
+    exit( -11);
+  }
+
+  initialize_constants();
+  image_f = (double *)calloc(N * N, sizeof(double));
+  if (image_f == NULL) {
+    printf("Unable to allocate the float array\n");
+    exit(1);
+  }
+
+  put_image_from_int_2_double(image_i, image_f, N);
+  fct2d(image_f, N, N);
+  add_watermark(image_f, N, coeff_start, wm_length, wm_key, wm_alpha);
+  ifct2d(image_f, N, N);
+  put_image_from_double_2_int(image_f, image_i, N);
+  save_image(image_i, out, width, height);
+  freematrix(image_i, height);
+  free(image_f);
+  fclose(in);
+  fclose(out);
+
+  exit(EXIT_SUCCESS);
+}