Wavelet Packet Based Video Coding in Parallel and Distributed Environments

This paper deals with different aspects of wavelet packet (WP) based video coding. In introducing experiments we show that WP decomposition and specifically WP decomposition in conjunction with the best basis algorithm are superior in terms of quality as compared to the standard discrete wavelet transform but show prohibitive computational demands (especially for real-time applications). The main contribution of our work is therefore the examination of three parallelization methods for WP based video coding. Two inter-frame based parallelization methods (group-of-picture parallelization and frame-by-frame parallelization) exploit the properties of a videostream (full independence between GOPs and rather high independence between single frames) better than inter-frame parallelization, but show a higher demand in terms of memory and don't respect the frame order defined by the input video stream. We highlight the advantages and drawbacks of all three methods and show experimental results obtained on a Siemens hpcLine cluster and a Cray T3E.