finding the grid

Works fine on the smaller image, worse on the bigger one.

diff --git a/commons.py b/commons.py
index 787a19d..fcfe469 100644 (file)
--- a/commons.py
+++ b/commons.py
@@ -3,5 +3,5 @@ import os
 def clear():
     if os.name == 'posix':
         os.system('clear')
 def clear():
     if os.name == 'posix':
         os.system('clear')

-    elif os.name == ('ce', 'nt', 'dos'):
+    elif os.name in ('ce', 'nt', 'dos'):

         os.system('cls')
         os.system('cls')

diff --git a/hough.py b/hough.py
index 7ac3aac..5fca93f 100644 (file)
--- a/hough.py
+++ b/hough.py
@@ -2,42 +2,89 @@ from PIL import Image
 from math import sin, cos, pi
 from commons import clear
 
 from math import sin, cos, pi
 from commons import clear
 

-def transform(image):
+class Hough:
+    def __init__(self, size):
+       self.size = size
+        self.dt = pi / size[1]
+        self.initial_angle = (pi / 4) + (self.dt / 2)

 
 

-    image_l = image.load()
-    size = image.size
-       
-    dt = pi / size[1]
-    initial_angle = (pi / 4) + (dt / 2)
+    def transform(self, image):
+        image_l = image.load()
+        size = image.size
+        
+        matrix = [[0]*size[1] for _ in xrange(size[0])]

 
 

-    matrix = [[0]*size[1] for _ in xrange(size[0])]
+        dt = self.dt
+        initial_angle = self.initial_angle

 
 

-    for x in xrange(size[0]):
-        clear()
-        print "hough transform: {0}/{1}".format(x + 1, size[0])
-        for y in xrange(size[1]):
-            if image_l[x, y]:
-                # for every angle:
-                for a in xrange(size[1]):
-                    # find the distance:
-                    # distance is the dot product of vector (x, y) - centerpoint
-                    # and a unit vector orthogonal to the angle
-                    distance = (((x - (size[0] / 2)) * sin((dt * a) + initial_angle)) + 
-                                ((y - (size[1] / 2)) * -cos((dt * a) + initial_angle)) +
-                                size[0] / 2)
-                    column = int(round(distance)) # column of the matrix closest to the distance
-                    if column >= 0 and column < size[0]:
-                        matrix[column][a] += 1
-
-    new_image = Image.new('L', size)
-    new_image_l = new_image.load()
-
-    minimum = min([min(m) for m in matrix])
-
-    maximum = max([max(m) for m in matrix]) - minimum
-
-    for y in xrange(size[1]):

         for x in xrange(size[0]):
         for x in xrange(size[0]):

-            new_image_l[x, y] = (float(matrix[x][y] - minimum) / maximum) * 255
+            clear()
+            print "hough transform: {0:>3}/{1}".format(x + 1, size[0])
+            for y in xrange(size[1]):
+                if image_l[x, y]:
+                    # for every angle:
+                    for a in xrange(size[1]):
+                        # find the distance:
+                        # distance is the dot product of vector (x, y) - centerpoint
+                        # and a unit vector orthogonal to the angle
+                        distance = (((x - (size[0] / 2)) * sin((dt * a) + initial_angle)) + 
+                                    ((y - (size[1] / 2)) * -cos((dt * a) + initial_angle)) +
+                                    size[0] / 2)
+                        column = int(round(distance)) # column of the matrix closest to the distance
+                        if column >= 0 and column < size[0]:
+                            matrix[column][a] += 1
+
+        new_image = Image.new('L', size)
+        new_image_l = new_image.load()
+
+        minimum = min([min(m) for m in matrix])
+
+        maximum = max([max(m) for m in matrix]) - minimum
+
+        for y in xrange(size[1]):
+            for x in xrange(size[0]):
+                new_image_l[x, y] = (float(matrix[x][y] - minimum) / maximum) * 255

             
             

-    return new_image
+        return new_image
+
+    def all_lines(self, image):
+       im_l = image.load()
+       lines = []
+       for x in xrange(image.size[0]):
+            for y in xrange(image.size[1]):
+               if im_l[x, y]:
+                   lines.append(self.angle_distance((x, y)))
+        return lines
+    
+    def find_angle_distance(self, image):
+        image_l = image.load()
+
+        points = []
+
+        count = 0
+        point_x = 0
+        point_y = 0
+        for x in xrange(image.size[0] / 2):
+            for y in xrange(image.size[1] / 2, image.size[1]):
+                if image_l[x, y]:
+                    count += 1
+                    point_x += x
+                    point_y += y
+        points.append((float(point_x) / count, float(point_y) / count))
+
+        count = 0
+        point_x = 0
+        point_y = 0
+        for x in xrange(image.size[0] / 2, image.size[0]):
+            for y in xrange(image.size[1] / 2, image.size[1]):
+                if image_l[x, y]:
+                    count += 1
+                    point_x += x
+                    point_y += y
+        points.append((float(point_x) / count, float(point_y) / count))
+
+        return [self.angle_distance(p) for p in points]
+
+    def angle_distance(self, point):
+       return (self.dt * point[1] + self.initial_angle, point[0] - self.size[0] / 2)
+       

diff --git a/imago.py b/imago.py
index bfa4c7a..6ab51a1 100755 (executable)
--- a/imago.py
+++ b/imago.py
@@ -2,10 +2,11 @@
 """Usage: imago.py file"""
 
 import sys
 """Usage: imago.py file"""
 
 import sys

-import Image
+import math
+import Image, ImageDraw

 import im_debug
 import filter
 import im_debug
 import filter

-import hough
+from hough import Hough

 
 class UsageError(Exception):
     def __init__(self, msg):
 
 class UsageError(Exception):
     def __init__(self, msg):


@@ -13,38 +14,122 @@ class UsageError(Exception):
 
 def main(*argv):
     """Main function of the program."""
 
 def main(*argv):
     """Main function of the program."""

+    
+    show_all = False
+

     try:
         if argv is ():
             argv = sys.argv[1:]
             if argv == []:
                 raise UsageError('Missing filename')
         if "--help" in argv:
     try:
         if argv is ():
             argv = sys.argv[1:]
             if argv == []:
                 raise UsageError('Missing filename')
         if "--help" in argv:

-                print __doc__
-                return 0    
+            print __doc__
+            return 0
+        if "--debug" in argv:
+            show_all = True

     except UsageError, err:
         print >>sys.stderr, err.msg, "(\"imago.py --help\" for help)"
         return 2
 
     except UsageError, err:
         print >>sys.stderr, err.msg, "(\"imago.py --help\" for help)"
         return 2
 

-    #TODO exception on file error
-    image = Image.open(argv[0])
-    #im_debug.show(image, "original image")
+    try:
+        image = Image.open(argv[0])
+    except IOError, msg:
+        print >>sys.stderr, msg
+        return 1
+    if show_all:
+       im_debug.show(image, "original image")

 
     im_l = image.convert('L')
 
     im_l = image.convert('L')

-    #im_debug.show(im_l, "ITU-R 601-2 luma transform")
+    if show_all:
+        im_debug.show(im_l, "ITU-R 601-2 luma transform")

 
     im_edges = filter.edge_detection(im_l)
 
     im_edges = filter.edge_detection(im_l)

-    #im_debug.show(im_edges, "edge detection")
-
-    im_h = filter.high_pass(im_edges, 80)
-    #im_debug.show(im_h, "high pass filter")
+    if show_all:    
+        im_debug.show(im_edges, "edge detection")

 
 

-    im_hough = hough.transform(im_h)
-    #im_debug.show(im_hough, "hough transform")
+    im_h = filter.high_pass(im_edges, 100)
+    if show_all:
+        im_debug.show(im_h, "high pass filter")
+    
+    hough1 = Hough(im_h.size)
+    im_hough = hough1.transform(im_h)
+    if show_all:
+        im_debug.show(im_hough, "hough transform")

 
     im_h2 = filter.high_pass(im_hough, 120)
 
     im_h2 = filter.high_pass(im_hough, 120)

-    im_debug.show(im_h2, "high pass filter")
+    if show_all:
+        im_debug.show(im_h2, "second high pass filter")
+
+    hough2 = Hough(im_h2.size)
+    im_hough2 = hough2.transform(im_h2)
+    if show_all:
+        im_debug.show(im_hough2, "second hough transform")
+
+    im_h3 = filter.high_pass(im_hough2, 120)
+    if show_all:
+       im_debug.show(im_h3, "third high pass filter")
+     
+    lines = hough2.find_angle_distance(im_h3)
+
+    im_lines = Image.new('L', im_h2.size)
+
+    draw = ImageDraw.Draw(im_lines)
+
+    for line in lines:
+       draw.line(line_from_angl_dist(line, im_h2.size), fill=255)
+    if show_all:
+       im_debug.show(im_lines, "lines")
+
+    im_c = combine(im_h2, im_lines)
+    if show_all:
+        im_debug.show(im_c, "first hough x lines")
+
+    collapse(im_c)
+    if show_all:
+        im_debug.show(im_c, "optimalised hough")
+
+    lines = hough1.all_lines(im_c)
+    draw = ImageDraw.Draw(image)
+    for line in lines:
+       draw.line(line_from_angl_dist(line, image.size), fill=(120, 255, 120))
+
+    im_debug.show(image, "the grid")

 
     return 0
 
 
     return 0
 

+def collapse(image):
+    #HACK
+    im_l = image.load()
+    last = False
+    for y in xrange(image.size[1]):
+       for x in xrange(image.size[0]):
+           if im_l[x,y] and last:
+                im_l[x, y] = 0
+               last = False
+           elif im_l[x, y]:
+               last = True
+           elif last:
+               last = False
+
+def combine(image1, image2):
+    im_l1 = image1.load()
+    im_l2 = image2.load()
+
+    im_n = Image.new('L', image1.size)
+    im_nl = im_n.load()
+
+    for x in xrange(image1.size[0]):
+        for y in xrange(image1.size[1]):
+           if im_l1[x, y] and im_l2[x, y]:
+               im_nl[x, y] = 255
+    return im_n
+
+def line_from_angl_dist((angle, distance), size):
+    x1 = - size[0] / 2
+    y1 = int(round((x1 * math.sin(angle) - distance)/math.cos(angle))) + size[1] / 2
+    x2 = size[0] / 2 
+    y2 = int(round((x2 * math.sin(angle) - distance)/math.cos(angle))) + size[1] / 2
+    return [(0, y1), (size[0] - 1, y2)]
+

 if __name__ == '__main__':
     sys.exit(main())
 if __name__ == '__main__':
     sys.exit(main())