Please correct me if I'm wrong (it happens all the time) but GIF images are not compressed as such, instead they use an index map into a pallette of colours.

GIF uses the Lempel-Ziv-Welch (LZW) compression algorithm, for which Unisys has a patent. There's a reasonably good explanation of the compression scheme here.

Once uncompressed, you get a matrix of indices into a color palette.

In reply to Re: Re: GIF Image Processing by dws
in thread GIF Image Processing by gri6507

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