--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Meerwald-dir/dwt.c	Fri Dec 20 13:08:59 2024 +0100
@@ -0,0 +1,361 @@
+#include "wm.h"
+#include "dwt.h"
+
+char filter_file[MAXPATHLEN] = "";
+AllFilters dwt_allfilters;
+FilterGH *dwt_filters = NULL;
+int dwt_method;
+int dwt_cols;
+int dwt_rows;
+int dwt_levels;
+int dwt_filter;
+
+void init_dwt(int cols, int rows, const char *filter_name, int filter, int level, int method) {
+  int i;
+
+  if (strcmp(filter_file, filter_name)) {
+    if (filter_name)
+      strcpy(filter_file, filter_name);
+    else
+      strcpy(filter_file, "filter.dat");
+
+    /* memory leak here - there is no function unload_filters() */
+    dwt_allfilters = load_filters(filter_file);
+
+    if (!dwt_allfilters) {
+      fprintf(stderr, "init_dwt(): unable to open filter definition file %s\n", filter_file);
+      return;
+    }
+  }
+
+#ifdef DEBUG
+  if (level <= 0 || level > rint(log(MIN(cols, rows))/log(2.0)) - 2) {
+    fprintf(stderr, "init_dwt(): level parameter does not match image width/height\n");
+    return;
+  }
+#endif
+
+  if (dwt_filters && level != dwt_levels) {
+    free(dwt_filters);
+    dwt_filters = NULL;
+  }
+
+  dwt_levels = level;
+
+  if (!dwt_filters)
+    dwt_filters = calloc(level + 1, sizeof(FilterGH));
+
+  for (i = 0; i < level + 1; i++)
+    dwt_filters[i] = (dwt_allfilters->filter)[filter];
+
+  dwt_filter = filter;
+  dwt_method = method;
+  dwt_cols = cols;
+  dwt_rows = rows;
+}
+
+Image_tree fdwt(gray **pixels) {
+  Image image;
+  Image_tree tree;
+  int i, j;
+
+  image = new_image(dwt_cols, dwt_rows);
+
+  for (i = 0; i < dwt_rows; i++)
+    for (j = 0; j < dwt_cols; j++)
+      set_pixel(image, j, i, pixels[i][j]);
+
+  tree = wavelettransform(image, dwt_levels, dwt_filters, dwt_method);
+  free_image(image);
+
+  return tree;
+}
+
+Image_tree fdwt_wp(gray **pixels) {
+  Image image;
+  Image_tree tree;
+  int i, j;
+
+  image = new_image(dwt_cols, dwt_rows);
+
+  for (i = 0; i < dwt_rows; i++)
+    for (j = 0; j < dwt_cols; j++)
+      set_pixel(image, j, i, pixels[i][j]);
+
+  tree = wavelettransform_wp(image, dwt_levels, dwt_filters, dwt_method);
+  free_image(image);
+
+  return tree;
+}
+
+void idwt(Image_tree dwts, gray **pixels) {
+  Image image;
+  int i, j;
+
+  image = inv_transform(dwts, dwt_filters, dwt_method + 1);
+
+  for (i = 0; i < dwt_rows; i++)
+    for (j = 0; j < dwt_cols; j++)
+      pixels[i][j] = PIXELRANGE((int) (get_pixel(image, j, i) + 0.5));
+
+  free_image(image);
+}
+
+void idwt_wp(Image_tree dwts, gray **pixels) {
+  Image image;
+  int i, j;
+
+  image = inv_transform(dwts, dwt_filters, dwt_method + 1);
+
+  for (i = 0; i < dwt_rows; i++)
+    for (j = 0; j < dwt_cols; j++)
+      pixels[i][j] = PIXELRANGE((int) (get_pixel(image, j, i) + 0.5));
+
+  free_image(image);
+}
+
+int gen_pollen_filter(double *filter, double alpha, double beta, int which) {
+  int i, j, k, filterlength;
+  double tf[6];
+
+  /* parameter alpha, beta have to be in range -Pi .. Pi */
+  if (alpha < -M_PI || alpha >= M_PI) {
+    fprintf(stderr, "alpha %f out of range\n", alpha);
+    return -1;
+  }
+
+  if (beta < -M_PI || beta >= M_PI) {
+    fprintf(stderr, "beta %f out of range\n", beta);
+    return -1;
+  }
+
+  /* generate Pollen filter coefficients, see http://www.dfw.net/~cody for details */
+  tf[0] = ((1.0 + cos(alpha) + sin(alpha)) * (1.0 - cos(beta) - sin(beta)) + 2.0 * sin(beta) * cos(alpha)) / 4.0;
+  tf[1] = ((1.0 - cos(alpha) + sin(alpha)) * (1.0 + cos(beta) - sin(beta)) - 2.0 * sin(beta) * cos(alpha)) / 4.0;
+  tf[2] = (1.0 + cos(alpha - beta) + sin(alpha - beta)) / 2.0;
+  tf[3] = (1.0 + cos(alpha - beta) - sin(alpha - beta)) / 2.0;
+  tf[4] = 1.0 - tf[0] - tf[2];
+  tf[5] = 1.0 - tf[1] - tf[3];
+
+  /* set close-to-zero filter coefficients to zero */
+  for (i = 0; i < 6; i++)
+    if (fabs(tf[i]) <  1.0e-15) tf[i] = 0.0;
+
+  /* find the first non-zero wavelet coefficient */
+  i = 0;
+  while (tf[i] == 0.0) i++;
+
+  /* find the last non-zero wavelet coefficient */
+  j = 5;
+  while (tf[j] == 0.0) j--;
+
+  filterlength = j - i + 1;
+  for (k = 0; k < filterlength; k++)
+    switch (which) {
+        case FILTERH:
+          filter[k] = tf[j--] / 2.0;
+          break;
+        case FILTERG:
+          filter[k] = (double) (((i & 0x01) * 2) - 1) * tf[i] / 2.0;
+          i++;
+          break;
+        case FILTERHi:
+          filter[k] = tf[j--];
+          break;
+        case FILTERGi:
+          filter[k] = (double) (((i & 0x01) * 2) - 1) * tf[i];
+          i++;
+          break;
+        default:
+          return -1;
+    }
+
+  while (k < 6)
+    filter[k++] = 0.0;
+
+  return filterlength;
+}
+
+void dwt_pollen_filter(double alpha, double beta) {
+  FilterGH filter;  
+  int i;
+
+  filter = malloc(sizeof(struct FilterGHStruct));
+#ifdef DEBUG
+  if (!filter) {
+    fprintf(stderr, "dwt_pollen_filter(): malloc failed()\n");
+    return;
+  }
+#endif
+
+  filter->type = FTOther;
+  filter->name = "pollen";
+
+  filter->g = new_filter(6);
+  filter->g->type = FTSymm;
+  filter->g->hipass = 1;
+  filter->g->len = gen_pollen_filter(filter->g->data, alpha, beta, FILTERG);
+  filter->g->start = -filter->g->len / 2;
+  filter->g->end = filter->g->len / 2 - 1;
+
+  filter->h = new_filter(6);
+  filter->h->type = FTSymm;
+  filter->h->hipass = 0;
+  filter->h->len = gen_pollen_filter(filter->h->data, alpha, beta, FILTERH);
+  filter->h->start = -filter->h->len / 2;
+  filter->h->end = filter->h->len / 2 - 1;
+
+  filter->gi = new_filter(6);
+  filter->gi->type = FTSymm;
+  filter->gi->hipass = 1;
+  filter->gi->len = gen_pollen_filter(filter->gi->data, alpha, beta, FILTERGi);
+  filter->gi->start = -filter->gi->len / 2;
+  filter->gi->end = filter->gi->len / 2 - 1;
+        
+  filter->hi = new_filter(6);
+  filter->hi->type = FTSymm;
+  filter->hi->hipass = 0;
+  filter->hi->len = gen_pollen_filter(filter->hi->data, alpha, beta, FILTERHi);
+  filter->hi->start = -filter->hi->len / 2;
+  filter->hi->end = filter->hi->len / 2 - 1;
+  
+#ifdef DEBUG
+  if (dwt_levels <= 0) {
+    fprintf(stderr, "dwt_pollen_filter(): level invalid - set to zero\n");
+    return;
+  }
+#endif
+
+#ifdef DEBUG
+  if (!dwt_filters) {
+    fprintf(stderr, "dwt_pollen_filter(): wm_dwt not initialized, call init_dwt() first\n");
+    return;
+  }
+#endif
+
+  for (i = 0; i < dwt_levels + 1; i++)
+    dwt_filters[i] = filter;
+}
+
+int gen_param_filter(double *filter, int n, double alpha[], int which) {
+  int i, j, k, filterlength;
+  double *tf, *t;
+
+  tf = malloc(2 * (n + 1) * sizeof(double));
+  t = malloc(2 * (n + 1) * sizeof(double));
+  if (!tf) {
+    fprintf(stderr, "gen_param_filter(): malloc() failed\n");
+    return -1;
+  }
+
+  tf[0] = 1.0 / sqrt(2.0);
+  tf[1] = 1.0 / sqrt(2.0);
+
+  for (k = 0; k < n; k++) {
+    for (i = 0; i < 2 * (k + 2); i++) {
+
+#define H(X) (((X) < 0 || (X) >= 2 * (k + 1)) ? 0.0 : tf[X])
+
+       t[i] = 0.5 * (H(i - 2) + H(i) +
+                     cos(alpha[k]) * (H(i - 2) - H(i)) +
+                     (i & 1 ? -1.0 : 1.0) * sin(alpha[k]) * (H(2 * (k + 2) - i - 1) - H(2 * (k + 2) - i - 3)));
+    }
+    for (i = 0; i < 2 * (k + 2); i++) tf[i] = t[i];
+  }
+
+  /* set close-to-zero filter coefficients to zero */
+  for (i = 0; i < 2 * (n + 1) ; i++)
+    if (fabs(tf[i]) <  1.0e-15) tf[i] = 0.0;
+
+  /* find the first non-zero wavelet coefficient */
+  i = 0;
+  while (tf[i] == 0.0) i++;
+        
+  /* find the last non-zero wavelet coefficient */
+  j = 2 * (n + 1) - 1;
+  while (tf[j] == 0.0) j--;
+
+  filterlength = j - i + 1;
+  for (k = 0; k < filterlength; k++)
+    switch (which) {
+        case FILTERG:
+        case FILTERGi:
+          filter[k] = (double) ((((i+1) & 0x01) * 2) - 1) * tf[i];
+          i++;
+          break;
+        case FILTERH:
+        case FILTERHi:
+          filter[k] = tf[j--];
+          break;
+        default: 
+          return -1;
+    }
+
+  while (k < 2 * (n + 1)) 
+    filter[k++] = 0.0;
+
+  return filterlength;
+}
+
+void dwt_param_filter(double alpha[], int param_len[]) {
+  FilterGH filter;  
+  int i;
+  int param_len_sum = 0;
+
+#ifdef DEBUG
+  if (dwt_levels <= 0) {
+    fprintf(stderr, "dwt_param_filter(): level invalid - set to zero\n");
+    return;
+  }
+#endif
+
+#ifdef DEBUG
+  if (!dwt_filters) {
+    fprintf(stderr, "dwt_param_filter(): wm_dwt not initialized, call init_dwt() first\n");
+    return;
+  }
+#endif
+
+
+  for (i = 0; i < dwt_levels + 1; i++) {
+
+    filter = malloc(sizeof(struct FilterGHStruct));
+#ifdef DEBUG
+    if (!filter) {
+      fprintf(stderr, "dwt_param_filter(): malloc failed()\n");
+      return;
+    }
+#endif
+
+    filter->type = FTOrtho;
+    filter->name = "param";
+
+    filter->g = new_filter(2 * (param_len[i] + 1));
+    filter->g->type = FTSymm;
+    filter->g->hipass = 1;
+    filter->g->len = gen_param_filter(filter->g->data,
+				      param_len[i], &alpha[param_len_sum],
+				      FILTERG);
+    filter->g->start = -filter->g->len / 2;
+    filter->g->end = filter->g->len / 2 - 1;
+
+    filter->h = new_filter(2 * (param_len[i] + 1));
+    filter->h->type = FTSymm;
+    filter->h->hipass = 0;
+    filter->h->len = gen_param_filter(filter->h->data,
+				      param_len[i], &alpha[param_len_sum],
+				      FILTERH);
+    filter->h->start = -filter->h->len / 2;
+    filter->h->end = filter->h->len / 2 - 1;
+
+    filter->gi = 0;
+    filter->hi = 0;
+
+    dwt_filters[i] = filter;
+
+    param_len_sum += param_len[i];
+  }
+}
+
+void done_dwt() {
+}