Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!mailrus!umix!umich!mibte!fmsrl7!oxtrap!hal!mandrill!abvax!gfs
From: gfs@abvax.UUCP (Greg F. Shay)
Newsgroups: comp.graphics
Subject: RE: 24bitcolor --> 8bit colormap
Message-ID: <221@abvax.UUCP>
Date: 14 Mar 88 14:57:04 GMT
Distribution: na
Organization: Allen-Bradley Company, Inc; Industrial Computer Division, Highland Heights, OH
Lines: 21
Keywords: Searching for: Median Cut Algorithm


Relating to the question of how to choose a 256 entry colormap to best
represent a 24bit full color image, the algorithm to use was published
by Paul Heckbert in the following:

	"Color image quantization for frame buffer display," SIGGRAPH 1982
Proceedings, pp.297-307.

I have this reference through another paper, but do not have a copy of the
paper itself.  I have posted a request for details from anyone who knows of
this.  As soon as I find out, I can post my findings.  For a rough outline of
the algorithm, which is very similiar to clustering algorithms in pattern
recognition I think, see my previous posting.

If anyone has the above paper, I would appreciate perhaps an address to get
a copy.  I will be checking the university library later.

		Greg Shay

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