filters.py

   1 from PIL import Image
   2
   3 from commons import clear
   4
   5 def edge_detection(image):
   6     clear()
   7     print "edge detection"
   8
   9     image_l = image.load()
  10     new_image = Image.new('L', image.size)
  11     new_image_l = new_image.load()
  12
  13     for x in range(2, image.size[0] - 2):
  14         for y in range(2, image.size[1] - 2):
  15             pix = (sum([sum([
  16                 image_l[a, b]
  17                     for b in range(y - 2, y + 3)])
  18                     for a in range(x - 2, x + 3)])
  19                 - (25 * image_l[x, y]))
  20             if pix > 255:
  21                 pix = 255
  22             if pix < 0:
  23                 pix = 0
  24             new_image_l[x, y] = pix
  25     return new_image
  26
  27 def peaks(image):
  28     clear()
  29     print "peak extraction"
  30
  31     image_l = image.load()
  32     new_image = Image.new('L', image.size)
  33     new_image_l = new_image.load()
  34
  35     for x in range(2, image.size[0] - 2):
  36         for y in range(2, image.size[1] - 2):
  37             pix = (sum([sum([
  38                 - image_l[a, b]
  39                     for b in range(y - 2, y + 3)])
  40                     for a in range(x - 2, x + 3)])
  41                 + (16 * image_l[x, y]))
  42             if pix > 255:
  43                 pix = 255
  44             if pix < 0:
  45                 pix = 0
  46             new_image_l[x, y] = pix
  47     return new_image
  48
  49 def high_pass(image, height):
  50     clear()
  51     print "high pass filter"
  52
  53     image_l = image.load()
  54     new_image = Image.new('L', image.size)
  55     new_image_l = new_image.load()
  56
  57     for x in xrange(image.size[0]):
  58         for y in xrange(image.size[1]):
  59             if image_l[x, y] < height:
  60                 new_image_l[x, y] = 0
  61             else:
  62                 new_image_l[x, y] = image_l[x, y]
  63
  64     return new_image
  65
  66 def components(image):
  67     clear()
  68     print "components center filter"
  69
  70     image_l = image.load()
  71     new_image = Image.new('L', image.size)
  72     new_image_l = new_image.load()
  73
  74     components = []
  75     comp_counter = 0
  76
  77     for y in xrange(1, image.size[1] - 1):
  78         for x in xrange(1, image.size[0] - 1):
  79             if image_l[x, y]:
  80                 s = {0}
  81                 s.add(new_image_l[x - 1, y - 1])
  82                 s.add(new_image_l[x, y - 1])
  83                 s.add(new_image_l[x + 1, y - 1])
  84                 s.add(new_image_l[x - 1, y])
  85                 if len(s) == 1:
  86                     components.append(set())
  87                     new_image_l[x, y] = comp_counter
  88                     components[comp_counter].add((x, y))
  89                     comp_counter += 1
  90                 elif len(s) == 2:
  91                     s.remove(0)
  92                     c = s.pop()
  93                     new_image_l[x, y] = c
  94                     components[c].add((x,y))
  95                 else:
  96                     s.remove(0)
  97                     c1, c2 = s.pop(), s.pop()
  98                     components[c2].add((x, y))
  99                     for (x1, y1) in components[c2]:
 100                         new_image_l[x1, y1] = c1
 101                     components[c1] = components[c1] | components[c2]
 102                     components[c2] = None
 103
 104     new_image = Image.new('L', image.size)
 105     new_image_l = new_image.load()
 106
 107     for component in components:
 108         if component:
 109             x_c = 0
 110             y_c = 0
 111             c = 0
 112             for (x, y) in component:
 113                 x_c += x
 114                 y_c += y
 115                 c += 1
 116         new_image_l[int(round(float(x_c)/c)), int(round(float(y_c)/c))] = 255
 117
 118
 119     return new_image