Efficient Pre-Coding Techniques for Wavelet-Based Image Compression∗
Detlev Marpe, Hans L. Cycon · 2003
In this paper we introduce a novel framework for the design of effective compression schemes using the discrete wavelet transform (DWT). Wavelet-based image compression schemes combine transform coding with subband coding techniques. Usually they consist of three modules: first and main part is an invertible transformation which decomposes the signal into dyadic structured subbands by convolution-decimation operations. It decorrelates mutually dependent parts and performs an energy compaction. The second module is a quantizer which annihilates visually non-relevant information, and the third and final part in this three-stage process consists of an entropy coder which removes redundancies in the stream of symbols generated by the quantizer. Many (very effective) research activities intend to optimize the transformation and/or the quantization in order to increase the compression performance of the coder [2] [4] [8]. In this paper, however, we use a non-sophisticated fast wavelet trans...