hipp v0.5819, an experimental command line file compressor by Bogatov Roman, uses context mixing with sparse contexts for binary data. Unfortunately, enwik9 cannot be compressed due to high memory requirements. ppmz2 v0.81, another compression tool by Charles Bloom, focuses on PPM and has various options. XMill 0.8, an AT&T project, preprocesses XML files for compression. lzp3o2, part of Charles Bloom’s compressors, uses LZP compression with order 2 modeling. The compression benchmark began in 2006, testing multiple compressors daily. Some compressors failed due to memory limits or improper file formatting. The ongoing updates reflect a continuous quest for efficient file compression methods.
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