Data Compression Debra

This paper surveys a variety of data compression methods spanning almost forty years of research, from the work of Shannon, Fano and Hu man in the late 40's to a technique developed in 1986. The aim of data compression is to reduce redundancy in stored or communicated data, thus increasing e ective data density. Data compression has important application in the areas of le storage and distributed systems. Concepts from information theory, as they relate to the goals and evaluation of data compression methods, are discussed brie y. A framework for evaluation and comparison of methods is constructed and applied to the algorithms presented. Comparisons of both theoretical and empirical natures are reported and possibilities for future research are suggested.