Is it possible to change the color of one individual pixel in Python?

Question

I need python to change the color of one individual pixel on a picture, how do I go about that?

Answer 1

To build upon the example given in Gabi Purcaru's link, here's something cobbled together from the PIL docs.

The simplest way to reliably modify a single pixel using PIL would be:

x, y = 10, 25
shade = 20

from PIL import Image
im = Image.open("foo.png")
pix = im.load()

if im.mode == '1':
    value = int(shade >= 127) # Black-and-white (1-bit)
elif im.mode == 'L':
    value = shade # Grayscale (Luminosity)
elif im.mode == 'RGB':
    value = (shade, shade, shade)
elif im.mode == 'RGBA':
    value = (shade, shade, shade, 255)
elif im.mode == 'P':
    raise NotImplementedError("TODO: Look up nearest color in palette")
else:
    raise ValueError("Unexpected mode for PNG image: %s" % im.mode)

pix[x, y] = value 

im.save("foo_new.png")

That will work in PIL 1.1.6 and up. If you have the bad luck of having to support an older version, you can sacrifice performance and replace pix[x, y] = value with im.putpixel((x, y), value).