Adaptive Wavelet Packet Image Coding with Zerotree Structure

Abstract

This chapter proposes an image compression method associating a wavelet packet and a zerotree coding scheme. The wavelet packet is employed to reduce the correlation of the image pixels. The wavelet packet is employed to reduce the correlation of the image pixels. To encode the coefficients, the chapter applies the zerotree structure, which can reduce the correlation across the decomposed component images. In this case, the decomposition criterion for each decomposition level is computed by simplified local zerotree structure. If a target bit rate or distortion is given, one can obtain the most suitable decompositions at the less computational operation. A multi-resolution analysis is employed to suppress the blocking effects that appear in the image coding scheme using the block transform such as discrete cosine transform (DCT). The decomposition has been applied to only the lower frequency component image recursively.