A Novel Image Coding Algorithm using Ant Colony System Vector Quantization

Ant colony system (ACS) is a combinatorial optimization method motivated by the behaviour of real ants. In this paper, we present a novel image coding method based on ACS vector quantization of groups of wavelet coefficients. The generation of codebook using ACS is facilitated by representing the coefficient vectors in a bidirectional graph, followed by defining a suitable mechanism of depositing pheromone on the edges of graph. Experimental results show that the quantization of zerotree vectors using ACS outperforms, in most cases, its traditionally used Linde-Buzo-Gray (LBG) counterpart.