I need python to change the color of one individual pixel on a picture, how do I go about that?
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2@akonsu: Judging by his tags he's already found that library... – Matti Virkkunen Aug 29 '10 at 20:20
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what file format? just bitmap data? – Nate Aug 29 '10 at 20:20
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The image is PNG format. – rectangletangle Aug 29 '10 at 20:23
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4read http://stackoverflow.com/questions/138250/read-the-rgb-value-of-a-given-pixel-in-python-programaticly – Gabi Purcaru Aug 29 '10 at 20:30
1 Answers
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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).
