Changeset 389 for pwntcha/trunk/src/filters.cTweet

Timestamp:

Jan 3, 2005, 10:48:54 PM (18 years ago)

Author:

Sam Hocevar

Message:

• use OpenCV rather than Imlib2 if both are available.
• cleaned up the slashdot code.
• decode phpBB captchas.
• added filter_contrast.

File:

• pwntcha/trunk/src/filters.c (modified) (4 diffs)

pwntcha/trunk/src/filters.c

@@ -143 +143 @@
 }
 
-struct image *filter_equalize(struct image *img)
+struct image *filter_equalize(struct image *img, int threshold)
 {
     struct image *dst;
@@ -155 +155 @@
         {
             getpixel(img, x, y, &r, &g, &b);
-            if(r < 200) r = 50; else r = 200;
+            if(r < threshold) r = 0; else r = 255;
             setpixel(dst, x, y, r, r, r);
         }
@@ -241 +241 @@
 struct image *filter_median(struct image *img)
 {
-#define MSIZE 4
+#define MSIZE 3
     struct image *dst;
     int x, y, i, j, val[MSIZE*MSIZE];
@@ -279 +279 @@
 }
 
+struct image *filter_contrast(struct image *img)
+{
+    struct image *dst;
+    int histo[256];
+    int x, y, i, min = 255, max = 0;
+    int r, g, b;
+
+    dst = image_new(img->width, img->height);
+
+    for(y = 0; y < img->height; y++)
+        for(x = 0; x < img->width; x++)
+        {
+            getgray(img, x, y, &r);
+            if(r < min) min = r;
+            if(r > max) max = r;
+        }
+
+    if(min == max)
+        histo[min] = 127;
+    else
+        for(i = min; i < max; i++)
+            histo[i] = (i - min) * 255 / (max - min);
+
+    for(y = 0; y < img->height; y++)
+        for(x = 0; x < img->width; x++)
+        {
+            getgray(img, x, y, &r);
+            setpixel(dst, x, y, histo[r], histo[r], histo[r]);
+        }
+
+    return dst;
+}
+