Implementation of a tree-structured vector quantizer for image compression on the MasPar MP-1 parallel machine

The transmission of digitized images over limited bandwidth channels motivates the use of data compression techniques. Many data compression techniques are not suitable for such applications because compression ratios of more than 20:1 are often required. One technique that can provide this level of compression is vector quantization. The processes of codebook generation and, especially, encoding and decoding are tasks well suited for execution on a massively parallel machine. For codebook generation, an SIMD algorithm is developed whose control flow is based on sequencing through the training data, rather than the tree structure, to achieve improved performance. Results from execution on the 16384 processor MasPar MP-1 SIMD machine are presented. The approaches taken could be adapted for other SIMD as well as MIMD machines