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RE: filmscanners: (anti)compression?
> >It turns out that it is impossible to create lossless compression scheme
> >that does not cause some files to expand in size. A set of random files
> >always expands. There is no way to encode the random information that
> does
> >not take up at least as much space as the original file. Because of
> this,
> >any image that contains lots of random noise tends to compress much less
> >than a high quality image with little noise.
>
>
> What about Genuine Fractals compression which claims non lossy
> compression and small file size.
>
The small file size will only occur for a subset of all possible images.
Hopefully this subset includes the majority of photographic images. The
best possible compression for an "image" that consists of nothing but random
data is a one bit flag to indicate that the rest of the file is untouched.
Luckily, most images are more interesting than random noise and compress
with the appropriate compressor.
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