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RE: Content negotiation: GIF v. PNG

From: Brian Gilkison <gilkison@one.net>
Date: Mon, 5 Mar 2001 16:51:49 -0500 (EST)
To: www-validator@w3.org
Message-ID: <Pine.LNX.4.21.0103051650230.9789-100000@shell.one.net>
On Mon, 5 Mar 2001, Peter Foti (PeterF) wrote:

> I question why this is done at all?  Why is PNG the preferred format?

See an explanation at http://kb.indiana.edu/data/aghf.html and/or
http://www.unisys.com/unisys/lzw/.  In a nutshell, GIF, TIFF, PostScript,
and PDF files use LZW compression which technically requires a license,
while JPEG, PNG, GNU zip (Gzip), StuffIt, and ZIP do NOT use LZW.  See
http://kb.indiana.edu/data/aekl.html for the advantages of PNG.

> It seems that if the validator was just changed to always offer the GIF
> file, then no one would have this problem, and the world would be a
> better place! :)  There would be no additional server configuration
> required, plus you wouldn't have to worry about supporting both a PNG

You're free (as I have) to change the validator source to output whatever
format you desire in the <img> tags; my current desire is to duplicate the
situation that exists on validator.w3.org and my ISP to my personal
testing server

> version and a GIF version of the file.  It would seem logical to rely on
> the method that is most portable and requires the least amount of
> configuring.

PNG = "Portable Network Graphics" -- how much more portable do you
want? :)

Brian
Received on Monday, 5 March 2001 16:52:27 GMT

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