Re: [AD] GIF patent / support

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What is JPEGs license? I assume you mean patent, since we could just
write our own code with our own license.

Angelo probably knows more about this issue... I think jpgalleg can't
decode some JPEGs for that reason (including those made by my digital
camera :()

JPGalleg comes with zlib/libpng license; I wrote all the code myself, except for the forward and inverse DCT routines. These have been derived from the libjpeg code (not copied; I've taken the algorithm, made some little optimizations and adapted to my purposes). The MMX FDCT routine is completely mine though. Also, the encoder default quantization and huffman tables comes from libjpeg sources, but even libjpeg claims they come from the official JPG specs, so no problems in using them. About JPG files JPGalleg can't load, it's probably because they are using arithmetic coding instead of huffman coding. This is a patented coding algorithm so it was not implemented in my lib. Most JPG files are huffman encoded though, so this is not really an issue. (By the way Evert: what JPGalleg version are you using? Latest is 2.5... Can you send me an image you can't load with it? I'll see if I can do something)

--
Angelo Mottola
a.mottola@xxxxxxxxxx
http://www.ecplusplus.com





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