Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!rutgers!ames!ucbcad!ucbvax!decvax!savax!elrond!amamaral
From: amamaral@elrond.CalComp.COM (Alan Amaral)
Newsgroups: sci.physics,comp.graphics,comp.sys.ibm.pc
Subject: Re: Color questions
Message-ID: <943@elrond.CalComp.COM>
Date: Thu, 11-Jun-87 12:35:58 EDT
Article-I.D.: elrond.943
Posted: Thu Jun 11 12:35:58 1987
Date-Received: Sat, 20-Jun-87 10:29:46 EDT
References: <1937@druhi.ATT.COM> <725@bsu-cs.UUCP> <6861@mimsy.UUCP> <20537@sun.uucp>
Distribution: comp
Organization: Calcomp, A Lockheed Company, Hudson, NH, USA
Lines: 27
Summary: trivial
Xref: mnetor sci.physics:1678 comp.graphics:788 comp.sys.ibm.pc:4866

In article <20537@sun.uucp>, falk@sun.uucp (Ed Falk) writes:
> Here's a related question, does anybody know the conversion factors to
> map colors in Red-Green-Blue space to Cyan-Yellow-Magenta-Black?  What
> I would like to do is generate four images on a high-res laser printer
> that can be used directly for printing; i.e. do the seperation in
> software.
> 
> 		-ed falk, falk@sun.com, sun!falk

It's trivial.

where R=G=B,
	then Black = 1-R (or G or B)
	C=M=Y=0
else

	black = 0
	+- -+	+- -+   +- -+
	| R |   | 1 |   | C |
	| G | = | 1 | - | M |
	| B |   | 1 |   | Y |
	+- -+   +- -+   +- -+
-- 
uucp:	 ...decvax!elrond!amamaral		I would rather be a
phone:	 (603) 885-8075				fool than a king...
us mail: Calcomp/Sanders DPD (PTP2-2D01)
	 Hudson NH 	03051-0908