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- compression as close to entropy as possible?

Subject: | compression as close to entropy as possible? |

Posted by: | Joey Dewille (joey19…@fastmail.co.uk) |

Date: | Tue, 6 Jul 2004 |

Hello group,

Is there an algorithm that satisfies these requirements:

1) it operates on the whole file, unlike other algorithms that partition a large file into buffers,

compress them individually and concatanate the results.

2) there exists a constant K :- 1 <= K < 1+C such that the compression ratio R achieved

by the algorithm satisfies: R < K * E / uncompressed_filesize, where E is the

entropy of the file and C is as small as possible (e.g. C < 0.2)

3) can be implemented in a programming language such as C

In other words the compression ratio approaches the entropy and is provably

only slightly higher at best.

- Re: compression as close to entropy as possible? posted by Thomas Richter on 6 Jul 2004
- Re: compression as close to entropy as possible? posted by Matt Mahoney on Thu, 15 Jul 2004