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From: sminkin@bbn.com (Scott Minkin)
Newsgroups: comp.graphics
Subject: Displaying 256 color GIFs on 16 color device
Message-ID: <49396@bbn.COM>
Date: 7 Dec 89 23:03:13 GMT
Sender: news@bbn.COM
Reply-To: sminkin@BBN.COM ()
Organization: Bolt Beranek and Newman Inc., Cambridge MA
Lines: 21

Greetings,

I've recently written a program to display GIF files on DEC VT340
terminals using color sixel.  The 16 color GIF files come out beutifully,
but I don't really have a scheme for converting 256 colors down to
16 (which is the limitation of the VT340).  Is there a preferred 
algorithm for doing this?  Averaging RGB values? Picking the 16 most
commonly used colors and trying to map the remaining colors to them?  

I've seen the source code to some other GIF decoders which handle the stripping
of color bits, but that seems to deal with devices with a limited resolution
for each color, rather than a limited number of colors.

Of course, the possibility that I'm misunderstanding this issue is also
a distinct possibility.

Any friendly advice would be greatly appreciated.

Thanks.
Scott
sminkin@bbn.com