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Wavelet packet zerotree image coding on multicomputers

In this paper, we describe and analyze algorithms for advanced image coding on distributed-memory MIMD architectures. In particular, we consider a wavelet packet-based image codec using the concept of zerotree encoding. The main contribution of this work is the design of a parallel image coder composed of a wavelet packet decomposition in conjunction with the best basis algorithm followed by zerotree coding. Whereas two sensible parallelization techniques can be employed for the wavelet packet decomposition (subband-based partitioning and stripe partitioning), the zerotree coding step only allows one reasonable parallelization method (stripe partitioning). We investigate the advantages and drawbacks of all combinations and show experimental results obtained on a Siemens hpcLine cluster and a Cray T3E.