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From: jroth@allvax.enet.dec.com (Jim Roth)
Newsgroups: comp.graphics
Subject: Re: Octree vs. Median Cut Color Quantization
Message-ID: <3310@ryn.esg.dec.com>
Date: 25 Oct 90 14:57:49 GMT
Sender: guest@ryn.esg.dec.com
Organization: Digital Equipment Corporation
Lines: 17


In article <579@lobster.NOSC.Mil>, gag@lobster.NOSC.Mil (Gary A. Gilbreath) writes...
> 
>Has anybody else out there implemented the octree quantization algorithm
>described in _Graphics Gems_, "A Simple Method for Color Quantization: Octree
>Quantization", by Gervautz and Purgathofer?

I haven't tried the Octree, but its main advantage would seem to be
simplicity and speed.  In my experience, a variance based assignment
gives the best results of all.  I've certainly never seen different
performance in different parts of the image!

Median or simple midpoint subdivision of bounding boxes does not work
as well as variance minimizing subdivision - there is a noticible
difference.

- Jim