Update cclabel.py

cclabel.py

@@ -7,14 +7,19 @@
 # by Kesheng Wu, Ekow Otoo, and Kenji Suzuki
 #
 
+
+
 import Image, ImageDraw
 
+
 import sys
 import math, random
 from itertools import product
 from ufarray import *
+import numpy as np
+
 
-def run(img):
+def bwlabel(img):
     data = img.load()
     width, height = img.size
 
@@ -112,6 +117,7 @@ def run(img):
     output_img = Image.new("RGB", (width, height))
     outdata = output_img.load()
 
+    count=0
     for (x, y) in labels:
 
         # Name of the component the current point belongs to
@@ -123,12 +129,45 @@ def run(img):
         # Associate a random color with this component 
         if component not in colors: 
             colors[component] = (random.randint(0,255), random.randint(0,255),random.randint(0,255))
+            count=count+1
 
         # Colorize the image
         outdata[x, y] = colors[component]
 
-    return (labels, output_img)
+## EDIT 
+#Creating a 2D numpy array(of size width*height)
+#Checks if there are more 1s than 0s and vice versa. It creates an array filled with zeros/ones appropriately
+    if((len(labels)*2) > width*height):
+        ccarr = np.ones((width, height))
+    else:
+        ccarr = np.zeros((width, height))
+
+# EDIT :The labeling that is done above has a disjoint sequence of integers
+#Eg: Components with labels 1, 2, 5 may exist. But there may be no components with labels 3 or 4.
+#This is because in the second pass, components are combined and hence certain labels are lost
+
+#Suppose there are 'N' components with labels c1, c2, ...,cN (where c1..cN is an arbitrary sequence of integers)
+#Labelswap associates the above sequence {c1...cN} to {1....N}
+#Also ccarr is now an array such that
+#       ccarr[i,j]=0                            , if the pixel was originally zero.
+#       ccarr[i,j]=some label between 1 & N     , if the pixel was originally part of a component
+
+    labelswap = {}
+    labelcount=1
+    for i in labels.keys():
+        lab = int(labels[i])
+        (a,b)=i
+        if lab in labelswap:
+            ccarr[a,b]=labelswap[lab]
+        else:
+            labelswap[lab]=labelcount
+            labelcount+=1
+            ccarr[a,b]=labelswap[lab]
+
+# EDIT : ccarr is returned instead of labels
+    return (ccarr, count, output_img)
 
+
 def main():
     # Open the image
     img = Image.open(sys.argv[1])
@@ -145,7 +184,7 @@ def main():
     # will want to use
     #
     # output_image is just a frivolous way to visualize the components.
-    (labels, output_img) = run(img)
+    (ccarr, count, output_img) = bwlabel(img)
 
     output_img.show()