Wavelet Based Embedded Image Coding Using Unified Zero-Block-Zero-Tree Approach

In this paper, we propose a unified approach of exploiting both inter- and intra-band correlations among the wavelet coefficients in a single algorithm. Most of the existing wavelet based image coding techniques are either based on zero-tree approach or zero-block (quad-tree) approach. The zero-tree based coders exploit only inter-band correlations whereas zero-block based coders exploit only intra-band correlations among the wavelet coefficients. Thus this work is an attempt to fuse the features of both block- and tree-based coding algorithms into a single algorithm. The proposed algorithm generates fully embedded bit stream. Simulation results show that the proposed algorithm outperforms existing wavelet based image coders. Additionally, the memory requirements due to the auxiliary lists is also reduced as compared to the zero-tree based coders