IMPLEMENTATION OF PHYSICAL COMPRESSION TECHNIQUES

Abstract

The increased usage of computer communication r-equires large scale information transfers to be implemented in a short time. One solution to this problem is to increase the existing communication facilities but it may not be cost effective. An alternate sclution is to apply a suitable physical data compression technique in which data is represented through more efficient codes (occupying less memory space) and than transmitted. The data can be recovered at the receiving and without loss. In this work five physical compression techniques namely Run length encoding, Bit mapping, Diatomic enco-ding, Half byte packing and Huffman coding have been analysed for their efficiency in handling different types of data sets and an algorithm, which is a combination of Huffman coding and a modified Bit map-ping is proposed. The data sets used for the analysis are of three types namely queries texts and databases and are of differen~ lengths. The results obtained in6icate that (a> Run length encoding is more efficient than other techniques in handling databases. (b) For handli g queries of short length Diatomic encoding is efficient whereas for longer queries the proposed algorithm is more efficient and (c) In processing texts the proposed algorithm becomes more efficient as the volume of text increases.