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History of Data Compression Algorithms

History of Data Compression Algorithms. By Michael Riha. Questions to Answer. How have compression algorithms evolved over time? What methods do they use to compress and how are they interrelated? What real-world applications do they have, and how have they changed?

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History of Data Compression Algorithms

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  1. History of Data Compression Algorithms By Michael Riha

  2. Questions to Answer • How have compression algorithms evolved over time? • What methods do they use to compress and how are they interrelated? • What real-world applications do they have, and how have they changed? • What priority do they place on speed vs. compression ratio? • What effect have software patents had on the development of compression algorithms?

  3. Sliding Window Algorithms • LZ77 (Lempel-Ziv #1) 1977 • LZSS (Lempel-Ziv-Storer-Szymanski) 1982 • LZRW (Lempel-Ziv Ross Williams) 1991 • LZJB (Lempel-Ziv Jeff Bonwick) 1998 • LZR (Lempel-Ziv-Renau) ??? • DEFLATE (ZIP, PNG, gzip, etc.) 1993 • DEFLATE64 (Proprietary) 1999 • LZS (Lempel-Ziv-Stac) 1994 • LZX (Used in Microsoft .CAB) 1995 • LZP (Usually a preprocessor) 1995 • LZO (Lempel-Ziv-Oberhumer) 1996 • LZMA (Lempel-Ziv-Markov Chain) 1998

  4. Dictionary Algorithms • LZ78 (Lempel-Ziv #2) 1978 • LZW (Lempel-Ziv-Welch) 1984 • LZMW (Syllable-based LZW) 1985 • LZAP 1988 • LZWL 2006 • bzip2 (Algorithm Amalgam) 1996 • PAQ* (Context Mixing) 2002 • PAQ8O (Faster, higher CR) 2007 • Many others • Statistical LZ • ROLZ (Reduced Offset LZ)

  5. Methods • Dictionary Compression (ubiquitous) • Prediction by Partial Matching (PPM, used by 7-Zip and RAR) • Context Mixing (Combines multiple statistical models) • Entropy Encoding • Huffman Coding (Used in DEFLATE, bzip2, SSH, etc.) • Adaptive Huffman Coding (Dynamic scope) • Shannon-Fano Coding (Suboptimal compared to Huffman) • Arithmetic & Range Encoding • Rice & Golomb Coding (FLAC uses Rice, not used general purpose) • Universal Coding (Slower than Huffman, uncommon) • Run-Length Encoding (AAAAAAABBBBA => 7A4BA) • Burrows-Wheeler Transform (Preprocessor for Run-length Encoding)

  6. Materials • Google Scholar / SJSU Library Databases • Regular Google • Wikipedia links to many detailed descriptions/specifications/implementations of algorithms • A few sources, mainly technical papers: • https://secure.wikimedia.org/wikibooks/en/wiki/Data_Compression/Dictionary_compression • http://www.maximumcompression.com/algoritms.php • https://tools.ietf.org/html/rfc1951 • http://www.cbloom.com/papers/lzp.html • http://www.larsson.dogma.net/dccpaper.pdf • http://ftp.informatik.rwth-aachen.de/Publications/CEUR-WS/Vol-176/paper5.pdf • Have not contacted any project advisors, not sure who would have expertise

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