Top Document: comp.compression Frequently Asked Questions (part 1/3) Previous Document: [12] I need source for the winners of the Dr Dobbs compression contest Next Document: [15] Where can I get image compression programs? See reader questions & answers on this topic!  Help others by sharing your knowledge (See question 70 for an introduction to arithmetic coding.) The source for the arithmetic coder described in Chap.5 of Bell, Cleary, and Witten's book "Text Compression" (see question 7 above) (or, equivalently, in: Witten, Neal, and Cleary's article "Arithmetic Coding for data Compression" from Communications of the Association for Computing Machinery, 30 (6), pp.520540, June, 1987) is in ftp://ftp.cpsc.ucalgary.ca/pub/projects/ar.cod/ It only comes with a simple order0 model but it's set up so that adding your own more sophisticated one is straightforward. Look also in ftp://munnari.mu.oz.au/pub/arith_coder C language source code for adaptive arithmetic coding based on the WittenNealCleary source code is in http://www.cipr.rpi.edu/wheeler/ac/ This version uses structures for the coder, decoder and data model instead of global variables. This object oriented approach allows you to simultaneously use several arithmetic coders, each streaming bits to a different file and to have several adaptive models for each coder, each with a different number of symbols and frequncy table. Written by Fred Wheeler <wheeler@cipr.rpi.edu> A low precision arithmetic coding implementation avoiding hardware division is available on the same site in ftp://ftp.cpsc.ucalgary.ca/pub/projects/arithmetic.coding/low.precision.version file low.precision.version.shar Kris Popat <popat@image.mit.edu> has worked on "Scalar Quantization with Arithmetic Coding." It describes an arithmetic coding technique which is quite general and computationally inexpensive. The documentation and example C code are available in ftp://ftp.media.mit.edu/pub/karithcode/ The program 'urban' in ddjcompr.zip (see item 12 above) is a high order arithmetic coder working at the bit level. It is written by Urban Koistinen <md85epi@nada.kth.se>. The DMC program is available in ftp://plg.uwaterloo.ca/pub/dmc/ It implements the algorithm described in "Data Compression using Dynamic Markov Modelling", by Gordon Cormack and Nigel Horspool, Computer Journal 30:6 (December 1987). This program uses Guazzo's version of arithmetic coding. An implementation of Moffat's arithmetic coder is available in http://www.cs.dartmouth.edu/~jmd/ArithCoder.tar.gz Michael Schindler <michael@compressconsult.com> provides a page on Range Coding http://www.compressconsult.com/rangecoder/ which includes an article and source code. According to Michael Schindler, the performance of that coder is a lot faster than the A. Moffat et al. CACAM coder or even the Moffat Data Compression Conference 1995 coder, at least for machines supporting a fast integer multipy and divide. User Contributions:Comment about this article, ask questions, or add new information about this topic:Top Document: comp.compression Frequently Asked Questions (part 1/3) Previous Document: [12] I need source for the winners of the Dr Dobbs compression contest Next Document: [15] Where can I get image compression programs? Part1  Part2  Part3  Single Page [ Usenet FAQs  Web FAQs  Documents  RFC Index ] Send corrections/additions to the FAQ Maintainer: jloup@gzip.OmitThis.org
Last Update March 27 2014 @ 02:11 PM
