Itterative detection of deflate parameters

From: byaarov@xxxxxxxxx
Date: 24 Mar 2007 09:36:15 -0700

I am trying to iteratively detect what deflate parameters (level and
memLevel) were used to compress the input stream.

My general approach is to initialize deflateInit2 with various
combinations of level and memLevel (81 combinations) and then see if I
can first inflate the input (a few bytes at a time), then pass those
bytes into deflate and see if the output compressed bytes match the
input.

In order to guarantee that deflate pushed all of its compressed bytes
into the output, should I be setting the flag Z_SYNC_FLUSH to each
call of deflate so that all the compressed bytes are available for
comparison?

B

.

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- Re: Itterative detection of deflate parameters
  - From: Mark Adler

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