Adaptive Wavelet Image Block Coding

In this paper a new approach for adaptive wavelet image coding is introduced. Based on an adaptive quadtree image-block partition (similar to fractal coding) the different image blocks may be compressed independently in an adaptive manner. In order to adapt to local image statistics and features we present several possibilities how to optimize the transform part of a wavelet image block-coder. Additionally we present a parallel algorithm suitable for MIMD architectures for efficient implementation of the proposed method. Finally experimental results concerning coding efficiency and execution time on a cluster of workstations are described. Keywords: image compression, wavelets, parallel algorithms, adaptive coding 1 INTRODUCTION In recent years there has been a tremendous increase in the demand for digital imagery. Applications include consumer electronics (Kodak's Photo-CD, HDTV and Sega's CD-ROM video game), medical imaging (digital radiography), video-conferencing and scientific v..