[Image-SIG] Converting from RGB to CMYK--Help!

Fredrik Lundh fredrik at pythonware.com
Mon Jul 17 17:12:35 CEST 2006

Medhat Assaad wrote:

> I am trying to convert an image from RGB to CMYK, so to test that I have
> this very small snippet of code:
> ----%-------
> import Image
> from sys import argv
> if __name__=='__main__':
>     if len(argv)==3:
>         Image.open(argv[1]).convert('CMYK').save(argv[2])
> ----%-------
> When I test this with an RGB png input (and save the output to a jpg
> file), I just get a black image as output. (I am using PIL 1.1.5 on
> Windows with Python 2.4.2)
> To make sure that it is not a problem I am having with "displaying" the
> cmyk file, I converted it back to rgb... and the rgb output was still
> black.
> Am I missing something?!

search the mailing list archives for a thread titled "Problem with JPEG 
and CMYK color space", which provides some background and a workaround.

alternatively, upgrade to 1.1.6 beta.


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