Article View: comp.sources.bugs
Article #666Re: Widespread bug in "compress" and GIF compressors
From: william E Davidsen
Date: Fri, 18 Dec 1992 13:36
Date: Fri, 18 Dec 1992 13:36
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In article <BzEzAM.3Gv.2@cs.cmu.edu>, tgl+@cs.cmu.edu (Tom Lane) writes:
| I've discovered a small bug in the standard Unix compress(1) utility.
| The bug is also present in many derived implementations of LZW compression,
| notably common GIF graphics file writers such as ppmtogif and xv.
I added this fix to ppmtogif, but I confess I don't see much change.
The output GIF images are different, they are still correct, they
produce the same output expanded, but they aren't notably smaller, even
when compressing cartoons and other images with tons of black and white
runs. I was expecting my cartoon collection to really shrink, but it
didn't.
What kind of image would benefit from this bugfix?
--
bill davidsen, GE Corp. R&D Center; Box 8; Schenectady NY 12345
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Path: arc1-ca.pugleaf.net!sparky!uunet!crdgw1!rdsunx.crd.ge.com!ariel!davidsen From: davidsen@ariel.crd.GE.COM (william E Davidsen) Newsgroups: comp.sources.bugs Subject: Re: Widespread bug in "compress" and GIF compressors Keywords: LZW, compress, GIF Message-ID: <1992Dec18.133623.13372@crd.ge.com> Date: 18 Dec 92 13:36:23 GMT References: <BzEzAM.3Gv.2@cs.cmu.edu> Sender: usenet@crd.ge.com (Required for NNTP) Reply-To: davidsen@crd.ge.com (bill davidsen) Organization: GE Corporate R&D Center, Schenectady NY Lines: 17 Nntp-Posting-Host: ariel.crd.ge.com