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Article #1161Re: calculating CMYK to RGB
From: Peter Pippinger
Date: Wed, 05 Mar 2003 08:36
Date: Wed, 05 Mar 2003 08:36
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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 -- www.FreeBSD.org is the be(a)st!
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X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 10c61a,c43968250f19a7ee,start X-Google-Attributes: gid10c61a,public X-Google-ArrivalTime: 2003-03-05 00:38:03 PST Path: arc1-ca.pugleaf.net!archiver1.google.com!news1.google.com!sn-xit-03!sn-xit-04!sn-xit-06!sn-xit-09!supernews.com!news.maxwell.syr.edu!nntp.infostrada.it!newsfeed01.sul.t-online.de!newsmm00.sul.t-online.com!t-online.de!news.t-online.com!not-for-mail 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 Organization: T-Online Lines: 25 Message-ID: <b44cto$g2l$01$1@news.t-online.com> References: <b44cru$rqo$06$1@news.t-online.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: news.t-online.com 1046853368 01 16469 sKGnEFSESTaRUq 030305 08:36:08 X-Complaints-To: abuse@t-online.com X-ID: rGmiH2ZeYei4hIvZVUF28HOFdVvQ9n-5zk0rmtUfB4zBPLmOTaaZg0 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106