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Article #1161

Re: calculating CMYK to RGB

#1161
From: Peter Pippinger
Date: Wed, 05 Mar 2003 08:36
23 lines
1966 bytes
Sorry, i was a bit to fast :-)

Hello there,

i have a big problem with converting colorspaces. When i use the
"standard"-formula to calculate the RGB-values for the monitor from an
CMYK-source i get poor results. I need them to be more close to the
printing-result. The formula i use:

Red = INT((1 - minimum(1, Cyan * (1 - Black) + Black))*255 + 0.5)
Green = INT((1 - minimum(1, Magenta * (1 - Black) + Black))*255 + 0.5)
Blue = INT((1 - minimum(1, Yellow * (1 - Black) + Black))*255 + 0.5)

now, if i "enter" values like C=100% M=0% Y=100% K=0% i get a result of R=0
G=255 B=0. But the color on the printer looks more like R=0 G=146 B=64. I
know professional applications use colormanagement. Has someone experiences
with converting colors?

Thanks a lot!
Peter

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From: "Peter Pippinger" <primergy@t-online.de>
Newsgroups: adobe.postscript.programming
Subject: Re: calculating CMYK to RGB
Date: Wed, 5 Mar 2003 09:36:14 +0100
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