#!BPY
"""
Name: 'bleed'
Blender: 249
Group: 'Image'
Tooltip: 'extend pixels at uv-borders'
"""

import Blender
from Blender import Image

background = [1.0,1.0,1.0,1.0] # white

#--------------------------------------------------------------------------------		
def clamp(x, a, b):
	if x < a: return a
	if x > b: return b
	return x

#--------------------------------------------------------------------------------		
def bleed(image, passes):
	print "extending pixels..."

	width, height = image.getMaxXY()
	
	def processpixel(x, y, ox, oy, image, original):
		ox = clamp(x + ox, 0, width - 1)
		oy = clamp(y + oy, 0, height - 1)
		c = image.getPixelF(ox, oy)
		if original[oy*width+ox] and c != background:
			image.setPixelF(x, y, c)
			return True
		return False
	
	for p in range(passes):
		print "  pass", p
		
		original = []
		for y in range(height):
			for x in range(width):
				if image.getPixelF(x, y) == background:
					original.append(False)
				else:
					original.append(True)
		
		for y in range(height):
			for x in range(width):
				if image.getPixelF(x, y) == background:
					if processpixel(x, y, 1, 0, image, original): continue
					if processpixel(x, y, 0, -1, image, original): continue
					if processpixel(x, y, -1, 0, image, original): continue
					if processpixel(x, y, 0, 1, image, original): continue



bleed(Image.GetCurrent(), 8)
Blender.Redraw()