Abraham Lempel

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Abraham Lempel

Abraham Lempel (born February 10, 1936 in Lemberg , Poland ) is an Israeli computer scientist of Polish origin . He is considered one of the fathers of data compression - algorithms LZ77 and LZ78 .


He studied at the Technion in Haifa in the Department for Electrical Engineering, where he received his bachelor's degree in 1963, his master's degree in 1965 and his doctorate in 1967. He then went to the University of Southern California as a research fellow . In 1969 he moved to the research staff at the Sperry Rand Research Center in Sudbury (Massachusetts) . In 1971 he went back to the Technion, where he works as a professor of computer science. Meanwhile he stayed at the Thomas J. Watson Research Center .

His historically significant works begin with the presentation of the LZ77 algorithm in a paper entitled “A Universal Algorithm for Sequential Data Compression” in IEEE Transactions on Information Theory , May 1977. This work was co-authored by Jacob Ziv .

The following algorithms each refer to Lempel by the letter L :

The identifiers LZX , LHA (LHarc) and LZH also refer to Lempel.

His work laid the foundations for compressed graphic formats such as GIF , TIFF and PNG .

In 1997 he received the Paris Kanellakis Prize .


  1. LZR was proposed in 1981 by Michael Rodeh , Vaughan R. Pratt and Shimon Even , see:
    • Michael Rodeh, Vaughan R. Pratt, Shimon Even: Linear Algorithm for Data Compression via String Matching . In: Journal of the ACM . tape 28 , no. 1 , January 1981, pp. 16-24 .
    • David Salomon, Giovanni Motta: Handbook of Data Compression . Springer Science & Business Media, 2010, ISBN 978-1-84882-903-9 , p. 338 ( limited preview in Google Book search).

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