money6g / ppm

Prediction by Partial Matching algorithm implementation

ppm

Prediction by Partial Matching data compression algorithm minimal implementation (no GUI provided).

Implemented by René Puchinger in 2007, revised in 2013.

The algorithm itself may be patented, therefore only academic usage is recommended.

Bibliography

• J.G. Cleary, and I.H. Witten, Data compression using adaptive coding and partial string matching, IEEE Transactions on Communications, Vol. 32 (4), pp. 396–402, April 1984.
• A. Moffat, Implementing the PPM data compression scheme, IEEE Transactions on Communications, Vol. 38 (11), pp. 1917–1921, November 1990.

Installation and Usage

1. After cloning the Git repo, navigate to src/ folder.

2. To compile, run

   g++ -o ppm *.cpp

3. Usage:

   ppm [c|d] input_file output_file

Example:

ppm c book.txt book.ppm
ppm d book.ppm book-orig.txt

Benchmark

A sample book in text format is available in the test-data/ folder. The algorithm may process arbitrary data, though.

Compression results of several compression applications (default settings) for the file book.txt:

Original size: 1 344 739 bytes

Compressed by ZIP: 490 883 bytes

Compressed by 7-Zip: 386 768 bytes

Compressed by BZ2: 349 584 bytes

Compressed by PPM: 323 934 bytes