Re: GIF again.....

[JD Smith <jdsmith(at)astro.cornell.edu>]

"Richard G. French" wrote:
> 
> After 5.4 came out, there were a lot of posts about the disappearance
> of the GIF writer and reader routines. Can any of you experts tell me
> about the legality of using shareware C code that reads and writes
> GIF files, originally used as part of the XV program that displays
> lots of image types on UNIX boxes? The idea would be to write
> wrapper routines that could call WriteGIF and ReadGIF in the XV
> code so that GIF writing and reading could be restored in IDL.
> 
> These routines are in the pub/xv subdirectory of
> ftp.cis.upenn.edu
> 
>         If this is not legal, does it mean that XV is not legal,
> either, even if you pay the registration fee?
> 
>         Has anyone come up with a legal scheme under UNIX to
> read and write GIF files? If you have to pay a license fee, does
> anyone know what the fee would be for a single user?
>         Thanks for any hints on workarounds.
> Dick French

http://www.imagemagick.org/

Seems to be the way to go.  Some enterprising tester of Ronn Kling's
book could even create a DLM which links to the ImageMagick libraries
and write GIF's directly.  Given that PNG is a better format 
(http://www.libpng.org/pub/png/pngintro.html), especially for the web,
maybe the interim convert-from-png route is preferrable.  We don't want
to make writing GIF's *too* easy.  For those who don't know of the GIF
(or rather LZW compression) issue:
http://cloanto.com/users/mcb/19950127giflzw.html

JD