Re: adaptive compressors vs non adaptive

On Sep 12, 12:40 pm, Marco Al <m.f...@xxxxxxxxxxx> wrote:
Desapa wrote:
Is there anybody that can suggests me a paper
that compares the performance of adaptive compressor vs
non adaptive ones?

From a purely theoretical point of view :

http://www.csse.monash.edu.au/~dld/MML.html

From a practical point of view ... it all depends on the source
distribution and the type of adaption you use. If the source is IID then
obviously the non adaptive coder will win on average.

Nothing much can be said about the general case, your question is too vague.

Regards,
Marco

Actually for an arithmetic (entropy) style compressor. If the source
is IID and the
information about the symbol rates is unknown such that it must be
passed
to the decompressor the adaptive will generally compress to a smaller
string
or file than where you have a separate table to be added to the string
or file
containing the probabilites. If you aready know in advance that its
IID and
you know in advance the rates then of course no adaption necessary but
in general knowing only that it is IID with the rates unknown the
adaptive does a better
job.


David A. Scott
--
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