X-Git-Url: http://git.tomasm.cz/imago.git/blobdiff_plain/ab71bc75ef14e2e731e92274b67988f6c0174061..f0548db6acfd9616ddafa443e45103fc6655e0e4:/filters.py?ds=inline

diff --git a/filters.py b/filters.py
index a5d00e6..c53b6e8 100644
--- a/filters.py
+++ b/filters.py
@@ -1,23 +1,13 @@
-from PIL import Image
+from PIL import Image, ImageFilter
+
+import pcf
 
 def edge_detection(image):
-    image_l = image.load()
-    new_image = Image.new('L', image.size)
-    new_image_l = new_image.load()
-    
-    for x in xrange(2, image.size[0] - 2):
-        for y in xrange(2, image.size[1] - 2):
-            pix = (sum([sum([
-                image_l[a, b] 
-                    for b in range(y - 2, y + 3)]) 
-                    for a in range(x - 2, x + 3)])
-                - (25 * image_l[x, y]))
-            if pix > 255:
-                pix = 255
-            if pix < 0:
-                pix = 0 
-            new_image_l[x, y] = pix
-    return new_image
+    image = image.filter(ImageFilter.GaussianBlur())
+    # GaussianBlur is undocumented class, it might not work in future versions
+    # of PIL
+    image = Image.fromstring('L', image.size, pcf.edge(image.size, image.tostring()))
+    return image
 
 def peaks(image):
     image_l = image.load()
@@ -30,7 +20,7 @@ def peaks(image):
                 - image_l[a, b] 
                     for b in range(y - 2, y + 3)]) 
                     for a in range(x - 2, x + 3)])
-                + (16 * image_l[x, y]))
+                + (17 * image_l[x, y]))
             if pix > 255:
                 pix = 255
             if pix < 0:
@@ -57,8 +47,8 @@ def components(image):
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()
 
-    components = []
-    comp_counter = 0
+    components = [None]
+    comp_counter = 1
 
     for y in xrange(1, image.size[1] - 1):
         for x in xrange(1, image.size[0] - 1):
@@ -99,37 +89,63 @@ def components(image):
                 x_c += x
                 y_c += y
                 c += 1
-        new_image_l[int(round(float(x_c)/c)), int(round(float(y_c)/c))] = 255
+            new_image_l[int(round(float(x_c)/c)), int(round(float(y_c)/c))] = 255
 
 
     return new_image
 
-def half_centers(image):
+def components2(image):
     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()
-    
-    x_s = 0
-    y_s = 0
-    n = 0
-    for x in range(0, image.size[0] / 2):
-        for y in range(0, image.size[1]):
-            if image_l[x, y] > 127:
-                x_s += x
-                y_s += y
-                n += 1
-    new_image_l[x_s / n, y_s / n] = 255
-
-    x_s = 0
-    y_s = 0
-    n = 0
-    for x in range(image.size[0] / 2, image.size[0]):
-        for y in range(0, image.size[1]):
-            if image_l[x, y] > 127:
-                x_s += x
-                y_s += y
-                n += 1
-    new_image_l[x_s / n, y_s / n] = 255
 
-    return new_image
+    components = [None]
+    comp_counter = 1
+
+    for y in xrange(2, image.size[1] - 2):
+        for x in xrange(2, image.size[0] - 2):
+            if image_l[x, y]:
+
+                s = {0}
+                for (a, b) in [(a,b) for a in range(x - 2, x + 3) 
+                          for b in range(y - 2, y + 1)]:
+                    if not (b == y and a >= x):
+                        s.add(new_image_l[a, b])
+
+                if len(s) == 1:
+                    components.append(set())
+                    new_image_l[x, y] = comp_counter
+                    components[comp_counter].add((x, y))
+                    comp_counter += 1
+                elif len(s) == 2:
+                    s.remove(0)
+                    c = s.pop()
+                    new_image_l[x, y] = c
+                    components[c].add((x,y))
+                else:
+                    s.remove(0)
+                    c1 = s.pop()
+                    components[c1].add((x, y))
+                    new_image_l[x, y] = c1
+                    for c2 in s:
+                        for (x1, y1) in components[c2]:
+                            new_image_l[x1, y1] = c1
+                        components[c1] = components[c1] | components[c2]
+                        components[c2] = None
+
+    new_image = Image.new('L', image.size)
+    new_image_l = new_image.load()
 
+    for component in components:
+        if component:
+            x_c = 0
+            y_c = 0
+            c = 0
+            for (x, y) in component:
+                x_c += x
+                y_c += y
+                c += 1
+            new_image_l[int(round(float(x_c)/c)), int(round(float(y_c)/c))] = 255
+
+
+    return new_image