Python - replace or remove colors from an image

from PIL import Image
 
# this script assumes that 'test.jpg' 
# is in the current working directory http://pythonicprose.blogspot.com/2009/09/python-os-module-and-working-directory.html 
n = Image.open('test.jpg')
m = n.load()
 
# get x,y size 
s = n.size
 
# iterate through x and y (every pixel) 
for x in xrange(s[0]):
    for y in xrange(s[1]):
        r,g,b = m[x,y]
        # remove red from the pic 
        m[x,y] = 0,g,b
 
# save the doctored image 
n.save('sans_red.jpg', "JPEG")
 
# removing all the red from a photo 
# makes for a creepy greenish blue (duh..with no red) 
# try it out!