[Image-SIG] Image.convert() doesn't dither?
janssen at parc.com
Tue Oct 25 02:39:07 CEST 2005
The PIL manual says that calling image.convert('1') on a greyscale
image will threshold the image (fairly starkly: "all non-zero values
are set to 255 (white).") However, when I try this on a test page of
color blocks, I seem to get Floyd-Steinberg dithering instead.
The code sequence I use is:
import Image, ImageOps
im = Image.open(infilename)
if im.mode == 'RGB':
im = ImageOps.grayscale(im)
if im.mode == 'L':
im = ImageOps.autocontrast(im)
im = im.convert('1')
Is the documentation out of date?
If I want thresholding, is there a now a way to do it without using
"point"? Using quantize(), perhaps?
Is there a difference between Image.convert('L') and
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