Performance issues in MPEG-4 VTC image coding

In this paper, we discuss how we can enhance the performance of the MPEG-4 Visual Texture Coding algorithm (VTC). Runtime analysis reveals the major coding stages and shows a weak point within the vertical filtering stage. A useful cache-access strategy is considered, which lifts this problem almost entirely. Additionally, we perform the DWT and the zerotree coding stage in parallel using OpenMP. The improved sequential version of the vertical filtering improves also the parallel efficiency significantly. We present results from 2 different multiprocessor platforms (SGI Power Challenge: 20 IP25 RISC CPUs, running at 195 Mhz; SGI Origin3800: 128 MIPS RISC R12000 CPUs, running at 400MHz).