[PYTHON IMAGE-SIG] Save a 5 bit gif as a 5 bit gif?

Fredrik Lundh Fredrik Lundh" <fredrik_lundh@ivab.se
Tue, 10 Jun 1997 14:10:22 +0200


>> The problem here is not really the bitdepth, it's the LZW patentl...
>
>Oops! Does this apply to the zlib also? I thought it was used in PIL,
>and there were no license prob? Or do I talk about different things.

LZW (as used in GIF, TIFF, PDF, Postscript, and compress) is
patented by Unisys (and also by IBM ;-). Unisys simply cannot
seem to understand that there's such things as free software
(they basically told one freeware author that he was an idiot
since he gave away software; had a quite absurd mail dialogue
with them myself which they explicitly told me I wasn't allowed
to post ;-).

The ZIP (aka deflate) compression (used in ZLIB, PNG, PDF,
recent Microsoft apps, various ZIP applications, squeeze, and
everyone else) is (most likely) patent free.

So, wherever you possible can, use PNG instead of GIF.

Unfortunately, too many browsers still don't support it
(MSIE 4 does, Netscape doesn't).

Cheers /F (yet another idiot ;-)



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