The Arithmetic Coding Page


Source code for the arithmetic coding routines described by Moffat, Neal, and Witten, "Arithmetic Coding Revisited", ACM Transactions on Information Systems, 16(3):256-294, July 1998, and the modified cumulative statistics structure described in "An Improved Data Structure for Cumulative Probability Tables", Software-Practice & Experience, 29(7):647-659, 1999.

(Note that the mechanism reported by Stuiver and Moffat is not currently included.)

Source code: arith_coder-3.tar.gz, February 1999.

Source code: Versions 1 (March 1995) and 2 (October 1996).

A suite of minimum-redundancy coding routines is also available, see


If compression programs are of interest to you, so will this book: Compression and Coding Algorithms by Alistair Moffat and Andrew Turpin, Kluwer Academic Publishers, Boston, March 2002.

You could also consider Managing Gigabytes: Compressing and Indexing Documents and Images by Ian H. Witten, Alistair Moffat, and Timothy C. Bell, Morgan Kaufmann, San Francisco, 1999.

Alistair Moffat
ammoffat /
January 16, 2002; January 13, 2013

Mandatory disclaimer: This page, its content and style, are the responsibility of the author and do not necessarily represent the views, policies, or opinions of The University of Melbourne.