Changing pixel color value in PIL
Question: I need to change pixel color of an image in python. Except for the pixel value
(255, 0, 0) red I need to change every pixel color value into black (0, 0, 0).
I tried the following code but it doesn't helped.

    
    
    from PIL import Image
    im = Image.open('A:\ex1.jpg')
    for pixel in im.getdata():
        if pixel == (255,0,0):
            print "Red coloured pixel"
        else:
            pixel = [0, 0, 0]
    


Answer: See this wikibook:
<https://en.wikibooks.org/wiki/Python_Imaging_Library/Editing_Pixels>

Modifying that code to fit your problem:

    
    
    pixels = img.load() # create the pixel map
    
    for i in range(img.size[0]): # for every pixel:
        for j in range(img.size[1]):
            if pixels[i,j] == (255, 0, 0):
                pixels[i,j] = (0, 0 ,0)
    

