HIERARCHICAL DICTIONARY MODEL AND DICTIONARY MANAGEMENT POLICIES FOR DATA-COMPRESSION

In this paper, an adaptive multi-dictionary model for data compression is proposed. Dictionary techniques applied in lossless compression co ding can be modeled from the dictionary management point of view which is similar to that of cache memory. The behavior of a compression tec hnique can be described by nine parameters defined in the proposed mod el, which provides a unified framework to describe the behavior of los sless compression techniques including existing probability-based Huff man coding and arithmetic coding, and dictionary-based LZ-family codin g and its variants. Those methods can be interpreted as special cases under the proposed model. New compression techniques can be developed by choosing proper management policies in order to meet special encodi ng/decoding software or hardware requirements, or to achieve better co mpression performance. (C) 1998 Elsevier Science B.V. All rights reser ved.