From: DavMac AT iname DOT com (Davin McCall)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: GIF File encoders...
Date: Sun, 19 Sep 1999 04:38:35 GMT
Organization: Monash Uni
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Actually, I believe only an implementation would be a patent
infringement (and then only if you hadn't obtained a license from
Unisys).

The actual LZW compression algorithm is widely known. I have a
document which describes it on my web site, if anyone's interested. (I
think in some ways it is worth reading, even if the actual technique
it describes is not going to be used due to patents and the like).

Davin.


On Sat, 18 Sep 1999 11:13:43 -0500, "Damian Yerrick"
<mail DOT me DOT at DOT your DOT own DOT risk AT pineight DOT 8m DOT com> wrote:

>I can't give that link to you. The GIF image format uses LZW
>compression, and Unisys owns the patent on LZW compression
>and will not license it to free software (GPL) developers.
>http://www.gnu.org/philosophy/gif.html
>http://lpf.ai.mit.edu/Patents/Gif/Gif.html
[...]
>But if I gave you GIF, that would be patent infringement.

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