Decoder complexity and performance comparison of matching pursuit and DCT-based MPEG-4 video codecs
Matching pursuits is an overcomplete expansion technique which has been successfully applied to the problem of coding motion residual images in a hybrid video coder. In this paper, the coding efficiency and decoder complexity of the method are compared to that of the DCT-based MPEG-4 standard with and without post-processing. Without post-processing, matching pursuits is shown to have significantly better PSNR and visual quality and similar decoding complexity compared to the MPEG-4 DCT decoder. To achieve reasonable quality at low bit rates, the DCT-based scheme requires post-processing, while the patching pursuit scheme does not. We show that the MPEG-4 post-processing filters have a prohibitive cost, increasing decoder complexity by a factor of 3 to 8. Finally, we introduce an all-integer matching pursuit implementation. The performance is shown to be within 0.05 dB of the original floating point algorithm.