Versions tested: 0.02
Optimal parameters: default
Authors: Sami Runsas
Algorithms: BWT+CM
Notable peformances: -


The program...

...implements a "compressed model" in which the data is kept compressed in memory all the time.

Compressed model program flow:

Compression: compression -> bwt -> compression
Decompression: decompression -> compression -> unbwt -> decompression

BWMonstr is able to perform BWT compression and decompression using about 0.5n space for English text. This is 10% of the amount that typical BWT implementations use and around 3% - 5% that of PPM or CM implementations.

The program supports multi-threading. In practice the speedup for compression translates in the following way:

2 processors: 1.57x
3 processors: 1.83x
4 processors: 2.25x

the program documentation


The compressor is featured in the BWT comparison.

(Have info that should be added here? E-mail.)

Disqualified (why) configurations (with qualification ratings)
Ver Rating CPR DPR S.E. R.E. Ratio C. kB/s D. kB/s
0.02 4 4 6 2 1 3.351 12 15

Version info

0.02, tar: yes, mode: 32-bit, crc32: b0fdab38, decoder: 68 kB, tested: 2010 Apr 19
compression: bwmonstr.exe e <src> <cfile>
decompression: bwmonstr.exe d <cfile> <src>