Path: utzoo!censor!becker!bdb
From: bdb@becker.UUCP (Bruce Becker)
Newsgroups: comp.graphics
Subject: Re: Fequency (wavelength) to CIE XYZ
Message-ID: <609@becker.UUCP>
Date: 28 Jun 89 14:14:03 GMT
References: <8594@pyr.gatech.EDU>
Reply-To: bdb@becker.UUCP (Bruce Becker)
Organization: G. T. S., Toronto, Ontario
Lines: 27

In article <8594@pyr.gatech.EDU> ccoprrm@pyr.gatech.edu.UUCP (ROBERT E. MINSK) writes:
|
|  Does anyone have a program or know of an algorithm to convert from
|Frequency (or wavelength) to CIE XYZ coordinate space.  I am not looking
|for CIE to RGB or for manipulations within the color space; this I 
|already know how to do.

	This is off the top of my head, so it will need some
	refinement...

	Tables exist in several places which map the periphery
	of the CIE standard visibility gamut in 5-nanometer
	increments (or sometimes other resolutions), expressed
	in CIE coordinates.
	Given this polygon, you can interpolate the wavelength
	into its border so as to arrive at the fully saturated
	CIE coordinate value. Other saturations occur monotonically
	on a line from there to the current reference white point.
	The transformation from the (x,y,Y) coordinate system
	(if needed), to (X,Y,Z) is simple.

Cheers,
-- 
   __	 Bruce Becker	Toronto, Ont.
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