refactored image component filters

[imago.git] / imago_pack / filters.py

diff --git a/imago_pack/filters.py b/imago_pack/filters.py
index 8c1c21b..a879ee9 100644 (file)
--- a/imago_pack/filters.py
+++ b/imago_pack/filters.py
@@ -1,16 +1,51 @@
+"""Image filters module.
+
+All filters return a filtered copy of the image, the original image is
+preserved.
+"""
+

 from PIL import Image, ImageFilter
 
 import pcf
 
 from PIL import Image, ImageFilter
 
 import pcf
 

+def color_enhance(image):
+    """Stretch all color channels to their full range."""
+    image_l = image.load()
+    min_r, min_g, min_b = 999, 999, 999
+    max_r, max_g, max_b = -1, -1, -1
+
+    for x in xrange(image.size[0]):
+        for y in xrange(image.size[1]):
+            min_r = min(min_r, image_l[x, y][0])
+            max_r = max(max_r, image_l[x, y][0])
+            min_g = min(min_g, image_l[x, y][1])
+            max_g = max(max_g, image_l[x, y][1])
+            min_b = min(min_b, image_l[x, y][2])
+            max_b = max(max_b, image_l[x, y][2])
+
+    new_image = Image.new('RGB', image.size)
+    new_image_l = new_image.load()
+    for x in xrange(image.size[0]):
+        for y in xrange(image.size[1]):
+            r, g, b = image_l[x, y]
+            r = (r - min_r) * 255 / (max_r - min_r)
+            g = (g - min_g) * 255 / (max_g - min_g)
+            b = (b - min_b) * 255 / (max_b - min_b)
+            new_image_l[x, y] = (r, g, b)
+
+    return new_image
+

 def edge_detection(image):
 def edge_detection(image):

-    image = image.filter(ImageFilter.GaussianBlur())
+    """Edge detection (on BW images)."""
+    new_image = image.filter(ImageFilter.GaussianBlur())

     # GaussianBlur is undocumented class, it might not work in future versions
     # of PIL
     # GaussianBlur is undocumented class, it might not work in future versions
     # of PIL

-    image = Image.fromstring('L', image.size,
+    new_image = Image.fromstring('L', image.size,

                              pcf.edge(image.size, image.tostring()))
                              pcf.edge(image.size, image.tostring()))

-    return image
+    return new_image

 
 def peaks(image):
 
 def peaks(image):

+    """Peak filter (on BW images)."""

     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()
     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()


@@ -30,6 +65,7 @@ def peaks(image):
     return new_image
 
 def high_pass(image, height):
     return new_image
 
 def high_pass(image, height):

+    """High pass filter (on BW images)."""

     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()
     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()


@@ -43,59 +79,9 @@ def high_pass(image, height):
 
     return new_image
 
 
     return new_image
 

-def components(image):
-    image_l = image.load()
-    new_image = Image.new('L', image.size)
-    new_image_l = new_image.load()
-
-    components = [None]
-    comp_counter = 1
-
-    for y in xrange(1, image.size[1] - 1):
-        for x in xrange(1, image.size[0] - 1):
-            if image_l[x, y]:
-                s = {0}
-                s.add(new_image_l[x - 1, y - 1])
-                s.add(new_image_l[x, y - 1])
-                s.add(new_image_l[x + 1, y - 1])
-                s.add(new_image_l[x - 1, y])
-                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, c2 = s.pop(), s.pop()
-                    components[c2].add((x, y))
-                    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
-
-def components2(image):
+def components(image, diameter):
+    # TODO comment 
+    # TODO refactor

     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()
     image_l = image.load()
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()


@@ -103,36 +89,67 @@ def components2(image):
     components = [None]
     comp_counter = 1
 
     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:
+    if diameter == 1:
+        for y in xrange(1, image.size[1] - 1):
+            for x in xrange(1, image.size[0] - 1):
+                if image_l[x, y]:
+                    s = {0}
+                    s.add(new_image_l[x - 1, y - 1])
+                    s.add(new_image_l[x, y - 1])
+                    s.add(new_image_l[x + 1, y - 1])
+                    s.add(new_image_l[x - 1, y])
+                    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, c2 = s.pop(), s.pop()
+                        components[c2].add((x, y))

                         for (x1, y1) in components[c2]:
                             new_image_l[x1, y1] = c1
                         components[c1] = components[c1] | components[c2]
                         components[c2] = None
                         for (x1, y1) in components[c2]:
                             new_image_l[x1, y1] = c1
                         components[c1] = components[c1] | components[c2]
                         components[c2] = None

+    elif diameter == 2:
+        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
+    else:
+        pass #TODO error
+

 
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()
 
     new_image = Image.new('L', image.size)
     new_image_l = new_image.load()


@@ -149,3 +166,4 @@ def components2(image):
             new_image_l[int(round(float(x_c)/c)), int(round(float(y_c)/c))] = 255
 
     return new_image
             new_image_l[int(round(float(x_c)/c)), int(round(float(y_c)/c))] = 255
 
     return new_image

+