Abraham Lempel

Abraham Lempel (Hebrew: אברהם למפל‎) is an Israeli (Polish-born) computer scientist and one of the fathers of the LZ family of lossless data compression algorithms. He is now a professor emeritus in Technion - Israel Institute of Technology.

His historically important works start with the presentation of the LZ77 algorithm in a paper entitled "A Universal Algorithm for Sequential Data Compression" in the IEEE Transactions on Information Theory (May 1977). This work was co-authored by Jacob Ziv. He has been named the recipient of the 2007 IEEE Richard W. Hamming Medal "For pioneering work in data compression, especially the Lempel-Ziv algorithm."

The following algorithms point with their letter L towards Lempel:

• 1977: LZ77 (Lempel–Ziv)
• 1978: LZ78 (Lempel–Ziv)
• 1984: LZW (Lempel–Ziv–Welch)
• LZR (LZ–Renau)
• LZS (Lempel–Ziv–Stac)
• LZO (Lempel–Ziv–Oberhumer)
• 2001: LZMA (Lempel–Ziv–Markov chain Algorithm)

The terms LZX, LHA (LHarc) and LZH do reference Lempel as well.

His works laid the basis for such compressed graphics formats as GIF, TIFF and JPEG.

Lempel founded HP Labs—Israel in 1994, and served as its director until October 2007.

He is the father of four sons, three of which are married. He has 8 grandchildren (7 girls and 1 boy).

Bibliography

• Jacob Ziv, Abraham Lempel (May 1977). "A Universal Algorithm for Sequential Data Compression" (PDF). IEEE Transactions on Information Theory 23 (3): 337–343. doi:10.1109/TIT.1977.1055714. 

See also

• Timeline of algorithms
• Data compression
• Oblivious transfer

External links

• 2007 IEEE Hamming Medal Recipient: Abraham Lempel.
• DBLP: Abraham Lempel.
• Senior HP Fellow: Abraham Lempel.
• Technion: Computer Science Department: Prof. Abraham Lempel.