Improved Compression ratio for Image Signal using First Order Differential Huffman Coding

Abstract

One of the most popular variable length coding technique for lossless image compression is Huffman
coding in which fewer bits are assigned to the symbols having less probability of occurrence and vice versa. Huffman
coding has significant application in JPEG coding and hence some extensions of Huffman coding technique like
Adaptive Huffman coding, Canonical Huffman coding and minimum variance Huffman coding have been proposed.
All these extensions are subjected to reduce decoding complexity or variance for encoding whereas our proposed
algorithm is designed to improve compression ratio achieved by conventional Huffman coding. By using simple first
order differential operator before applying Huffman coding technique, we have obtained significant improvement in
compression ratio in case of image signal.