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. I would have thought, then, that you can apply your image detection algorithm on the matrix of indices.

Update:Thanks to dws :). I forgot all about the Unisys patent and the compression algorithm wrangles.

I don't have my notes anymore but I did something similar on a raw binary file at University. Essentially the algorithm worked by taking a group ok3x3 matrices and applying them successively to a set of data. Depending on the final result, it recorded a 1 (an edge) or a 0.

My gut feeling is that you may not be able to get away without first changing the indices for the actual binary values. However, thats just a hunch :)

I still have the code somewhere but its in OCCAM and is designed to run on a transputer network so I don't know how useful it may be to you.

In reply to Re: GIF Image Processing by simon.proctor
in thread GIF Image Processing by gri6507

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