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MP3D: highly scalable video coding scheme based on matching pursuit

The paper describes a novel video coding scheme based on a three-dimensional matching pursuit algorithm. In addition to good compression performance at low bit rates, the proposed coder allows for flexible spatial, temporal and rate scalability thanks to its progressive coding structure. The matching pursuit algorithm generates a sparse decomposition of a video sequence in a series of spatio-temporal atoms, taken from an overcomplete dictionary of three-dimensional basis functions. The dictionary is generated by shifting, scaling and rotating two different mother atoms in order to cover the whole frequency cube. An embedded stream is then produced from the series of atoms. They are first distributed into sets through the set-partitioned position map algorithm (SPPM) to form the index-map, inspired from bit plane encoding. Scalar quantization is then applied to the coefficients which are finally arithmetic coded. A complete MP3D codec has been implemented, and performances are shown to compare favorably to other scalable coders like MPEG-4 FGS and SPIHT-3D. In addition, the MP3D streams offer an incomparable flexibility for multiresolution streaming or adaptive decoding.