# Abraham Lempel

**Abraham Lempel** (Hebrew: אברהם למפל, born 10 February 1936) is an Israeli computer scientist and one of the fathers of the LZ family of lossless data compression algorithms.

Abraham Lempel | |
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Abraham Lempel in 2007 | |

Born | |

Residence | Israel |

Known for | LZ77, LZ78 |

Awards | Paris Kanellakis Award (1997) IEEE Richard W. Hamming Medal (2007) |

Scientific career | |

Fields | Information theory |

Institutions | Technion - Israel Institute of Technology |

## Biography

Lempel was born on 10 February 1936 in Lwów, Poland (now Lviv, Ukraine).[1] He studied at Technion - Israel Institute of Technology, and received a B.Sc. in 1963, M.Sc. in 1965, and D.Sc. in 1967. Since 1977 he has held the title of full professor. Lempel is now a professor emeritus in Technion.

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), co-authored by Jacob Ziv.

He is the recipient of the 1998 Golden Jubilee Award for Technological Innovation from the IEEE Information Theory Society;[2] and the 2007 IEEE Richard W. Hamming Medal, for "pioneering work in data compression, especially the Lempel-Ziv algorithm".[3]

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

## Works

The LZ77 and LZ78 algorithms authored by Lempel and Jacob Ziv have led to a number of derivative works, including the Lempel–Ziv–Welch algorithm, used in the GIF image format, and the Lempel-Ziv-Markov chain algorithm, used in the 7-Zip and xz compressors. The algorithms have also been used as originally published in formats such as DEFLATE, used in the PNG image format.

## Bibliography

- Jacob Ziv, Abraham Lempel (May 1977). "A Universal Algorithm for Sequential Data Compression".
*IEEE Transactions on Information Theory*.**23**(3): 337–343. CiteSeerX 10.1.1.118.8921. doi:10.1109/TIT.1977.1055714.

## References

- "IEEE Transactions On Computers: Contributors". Institute of Electrical and Electronics Engineers. December 1970. Retrieved 2014-10-30.
- "Golden Jubilee Awards for Technological Innovation". IEEE Information Theory Society. Retrieved 2014-10-30.
- "IEEE Richard W. Hamming Medal Recipients" (PDF). IEEE. Retrieved 2014-10-30.

## External links

- Abraham Lempel – GHN: IEEE Global History Network
- Abraham Lempel at DBLP Bibliography Server
- Technion: Computer Science Department: Prof. Abraham Lempel
- "Abraham Lempel: Senior HP Fellow". Archived from the original on July 6, 2008. Retrieved June 9, 2009.
- Abraham Lempel at the Mathematics Genealogy Project