From: elee9sf@Menudo.UH.EDU
Date: Fri, 21 May 93 07:39:13 PDT
To: cypherpunks@toad.com
Subject: Re: Huffman and Crypto
In-Reply-To: <9305201955.AA05279@smds.com>
Message-ID: <199305211439.AA00169@Menudo.UH.EDU>
MIME-Version: 1.0
Content-Type: text/plain




> 3) Does anyone know of an easy-to-get-sources, easy-to-use arithmetic
>    coding compression program?
> 

I have a book titled "Data Compression" or something like that, which
explains Huffman and Huffman-type coding, arithmetic coding,
dictionary compressers (sliding window LZ* types), and JPEG
compression.  The book comes with source code, so if anybody else has
it and has a scanner...

As I recall, arithmetic compression works well, but is really cpu
intensive, even with a math-coprocessor.  Plus, you need to have a
rough idea of the statistical breakdown of the plaintext for
arithmetic compression to work as well as it can.  The Zimpel-Lev type
sliding window compressors are popular because they work well on most
inputs, with little or no pre-computation or statistics.

Isn't Phil Karn on this list?  I'm sure he can tell you everything you
want to know about compression :-)

/-----------------------------------\
| Karl L. Barrus                    |
| elee9sf@menudo.uh.edu             | <- preferred address
| barrus@tree.egr.uh.edu (NeXTMail) |
\-----------------------------------/