A New Update Step for Reduction of PSNR Fluctuations in Motion-Compensated Lifted Wavelet Video Coding

摘要

In wavelet video coding, due to motion-compensation entwined in the temporal wavelet transform, the distortion in the temporal subbands propagates in an uneven manner into the reconstructed frames of a group of pictures. This leads to fluctuation of reconstruction quality in time, which can be visually displeasing. We propose a new update step which is derived by taking into account a Lagrangian term for even distribution of distortion among reconstructed frames in addition to minimizing total distortion. Additionally some heuristics for the implementation of this new update step are proposed. Experimental results show reduction of quality fluctuation compared to the conventional update step