Apache-Talk @lexa.ru 

Inet-Admins @info.east.ru 

Filmscanners @halftone.co.uk 

Security-alerts @yandex-team.ru 

nginx-ru @sysoev.ru 

   


   


   















      :: Filmscanners
Filmscanners mailing list archive (filmscanners@halftone.co.uk)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

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.  




 




Copyright © Lexa Software, 1996-2009.