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From: raveling@venera.isi.edu (Paul Raveling)
Newsgroups: comp.graphics
Subject: Re: Color Quantization (was Re: Discussion of Computer Pornography)
Message-ID: <8490@venera.isi.edu>
Date: 25 May 89 16:37:18 GMT
References: <4706@uoregon.uoregon.edu> <310@celit.UUCP> <8478@venera.isi.edu> <9445@polya.Stanford.EDU>
Reply-To: raveling@venera.isi.edu (Paul Raveling)
Organization: Information Sciences Institute, Univ. of So. California
Lines: 25

In article <9445@polya.Stanford.EDU> rokicki@polya.Stanford.EDU (Tomas G. Rokicki) writes:
>
>Wouldn't it make sense to do color selection in the HSV cone rather
>than in the RGB cube, since the `distances' in HSV are more relevant
>to perceived differences in color?

	Maybe, but it's not clear.  About a year ago I tried some
	experiments using a different perceptual space suggested in
	a paper by Werner Frei, but got essentially the same end results
	as using RGB space.  It's possible that limitations in the
	quantization algorithm could mask the benefits of using a
	different space; the best solution probably requires coordinated
	work to evolve both the color domain and algorithms using it.

	There are also some applications of quantization that would
	need an approach not based on human perception.  I'm thinking
	of things such as multispectral imaging, including infrared,
	UV, X-ray, and magnetic resonance imaging.  Some applications
	might call for a "linear" quantization, some might benefit
	by weighting for a "non-human" domain.


----------------
Paul Raveling
Raveling@isi.edu