Flexible distribution of complexity by hybrid predictive-distributed video coding

There is currently limited flexibility for distributing complexity in a video coding system. While rate-distortion-complexity (RDC) optimization techniques have been proposed for conventional predictive video coding with encoder-side motion estimation, they fail to offer true flexible distribution of complexity between encoder and decoder since the encoder is assumed to have always more computational resources available than the decoder. On the other hand, distributed video coding solutions with decoder-side motion estimation have been proposed, but hardly any RDC optimized systems have been developed. To offer more flexibility for video applications involving multi-tasking or battery-constrained devices, in this paper, we propose a codec combining predictive video coding concepts and techniques from distributed video coding and show the flexibility of this method in distributing complexity. We propose several modes to code frames, and provide complexity analysis illustrating encoder and decoder computational complexity for each mode. Rate distortion results for each mode indicate that the coding efficiency is similar. We describe a method to choose which mode to use for coding each inter frame, taking into account encoder and decoder complexity constraints, and illustrate how complexity is distributed more flexibly

Wyner-ziv coding with temporal and spatial correlations for motion video

Distributed video coding (DVC), now has become one of the fastest evolving coding techniques in the current signal processing world. It has its remarkable low complex yet powerful encoder which is essential for some applications in the consumer market. In this paper we propose a novel Wyner-Ziv architecture that splits a frame in to two sub frames and leave one as a Key sub frame while encoding the other as a WZ sub frame. The split key sub frame is encoded using a conventional coding scheme as in the other DVC techniques. At the decoder end the sub key frame is used to exploit the spatial and temporal correlations using an intra prediction technique and temporal motion search in order to generate the side information for the corresponding WZ sub frame. Simulation results show that over 1 dB PSNR gain can be obtained with the proposed algorithm over the results of the algorithm presented in the literature [7] at the same bit rate