## Practical Use of The Warm-up Algorithm on Length-Restricted Coding (1997)

Venue: | the Proceedings of the Fourth Latin American Workshop on String Processing |

Citations: | 4 - 4 self |

### BibTeX

@INPROCEEDINGS{Milidiú97practicaluse,

author = {Ruy Luiz Milidiú and Artur Alves Pessoa and Eduardo Sany Laber},

title = {Practical Use of The Warm-up Algorithm on Length-Restricted Coding},

booktitle = {the Proceedings of the Fourth Latin American Workshop on String Processing},

year = {1997},

pages = {80--94},

publisher = {Carleton University Press}

}

### OpenURL

### Abstract

. In this paper we present an efficient implementation of the WARM-UP Algorithm for the construction of length-restricted prefix codes. This algorithm has O(n log n + n log wn) worst case time complexity, where n is the number of symbols of the source alphabet and wn is the largest weight of the alphabet. An important feature of the proposed algorithm is its implementation simplicity. The algorithm is basically a selected sequence of Huffman trees construction for modified weights. The proposed implementation has the same time complexity, but requires only additional O(1) space. We also report some empirical experiments showing that this algorithm provides good compression and speed performances. 1 Introduction An important problem in the field of Coding and Information Theory is the Binary Prefix Code Problem. Given an alphabet \Sigma = fa 1 ; : : : ; ang and a corresponding set of positive weights fw 1 ; : : : ; wng, the problem is to find a prefix code for \Sigma that mi...

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Citation Context ...gth P n i=1 l i . The 1 In a full binary tree each internal node has exactly two sons. objective is to allow space efficient decoding of optimal prefix codes without bitmanipulation. Zobel and Moffat =-=[Zob95]-=- describe the use of word-based Huffman codes for compression of large textual databases. The application allows the maximum of 32 bits for each codeword. For the cases that exceed this limitation, it... |