Re: how to convert (C,M,Y) colours to (R,G,B)?

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#2745

From: John Grant
Date: Tue, 12 Jan 1993 23:26

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In article <1993Jan11.221759.7441@sierra.com> paul@sierra.com (Paul Stratton) writes:
>In article <1993Jan7.211624.27277@emr1.emr.ca> jagrant@emr1.emr.ca (John Grant) writes:
[stuff deleted]
>
>It really is simple.  For example if your CMY is in the range of 0 - 255
>and you have a CMY value of (4, 195, 80) then the RGB value is
>
>	255 - 4
>	255 - 195
>	255 - 80
>
>The only problem is I can't remember which CMY go with which RGB!  I haven't
>done this in a while.
	Yeah, I found it already:
		R=1-C
		G=1-M
		B=1-Y
	assuming that all of r,g,b,c,m,y are [0,1] range.
	or:
		R=255-C
		G=255-M
		B=255-Y
	assuming all are [0,255].  This makes sense since
	(c,m,y)=(0,0,0) is white (i.e. no paint on paper) and white
	is also (r,g,b)=(255,255,255), i.e. all guns turned on,
	summing to white.
-- 
John A. Grant						jagrant@emr1.emr.ca
Airborne Geophysics
Geological Survey of Canada, Ottawa

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Path: arc1-ca.pugleaf.net!sparky!uunet!noc.near.net!hri.com!spool.mu.edu!howland.reston.ans.net!usc!cs.utexas.edu!torn!nott!emr1!jagrant
From: jagrant@emr1.emr.ca (John Grant)
Newsgroups: comp.os.ms-windows.programmer.misc
Subject: Re: how to convert (C,M,Y) colours to (R,G,B)?
Message-ID: <1993Jan12.232630.7796@emr1.emr.ca>
Date: 12 Jan 93 23:26:30 GMT
References: <1993Jan7.211624.27277@emr1.emr.ca> <1993Jan11.221759.7441@sierra.com>
Organization: Energy, Mines, and Resources, Ottawa
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