# SUFFIX ARRAYS - A Competitive Choice for Fast Lempel-Ziv Compressions

### Artur J. Ferreira, Arlindo L. Oliveira, Mário A. T. Figueiredo

#### Abstract

Lossless compression algorithms of the Lempel-Ziv (LZ) family are widely used in a variety of applications. The LZ encoder and decoder exhibit a high asymmetry, regarding time and memory requirements, with the former being much more demanding. Several techniques have been used to speed up the encoding process; among them is the use of suffix trees. In this paper, we explore the use of a simple data structure, named suffix array, to hold the dictionary of the LZ encoder, and propose an algorithm to search the dictionary. A comparison with the suffix tree based LZ encoder is carried out, showing that the compression ratios are roughly the same. The ammount of memory required by the suffix array is fixed, being much lower than the variable memory requirements of the suffix tree encoder, which depends on the text to encode. We conclude that suffix arrays are a very interesting option regarding the tradeoff between time, memory, and compression ratio, when compared with suffix trees, that make them preferable in some compression scenarios.

#### References

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#### Paper Citation

#### in Harvard Style

J. Ferreira A., L. Oliveira A. and A. T. Figueiredo M. (2008). **SUFFIX ARRAYS - A Competitive Choice for Fast Lempel-Ziv Compressions** . In *Proceedings of the International Conference on Signal Processing and Multimedia Applications - Volume 1: SIGMAP, (ICETE 2008)* ISBN 978-989-8111-60-9, pages 5-12. DOI: 10.5220/0001935200050012

#### in Bibtex Style

@conference{sigmap08,

author={Artur J. Ferreira and Arlindo L. Oliveira and Mário A. T. Figueiredo},

title={SUFFIX ARRAYS - A Competitive Choice for Fast Lempel-Ziv Compressions},

booktitle={Proceedings of the International Conference on Signal Processing and Multimedia Applications - Volume 1: SIGMAP, (ICETE 2008)},

year={2008},

pages={5-12},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0001935200050012},

isbn={978-989-8111-60-9},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the International Conference on Signal Processing and Multimedia Applications - Volume 1: SIGMAP, (ICETE 2008)

TI - SUFFIX ARRAYS - A Competitive Choice for Fast Lempel-Ziv Compressions

SN - 978-989-8111-60-9

AU - J. Ferreira A.

AU - L. Oliveira A.

AU - A. T. Figueiredo M.

PY - 2008

SP - 5

EP - 12

DO - 10.5220/0001935200050012