Efficient Intra Mode Selection Using Motion Affected Region Tracking

Intra refresh is well-known as an efficient technique for eliminating temporal error propagation in a predictive video coding system. This paper proposes a novel intra refresh method based on motion affected region tracking (MTIR) for real time video communication systems. For every frame between two successive intra refresh frames, the motion affected regions are statistically analyzed to achieve the error sensibility of macroblocks, and then the error sensitive macroblocks are intra coded. To suppress the potential spatial and temporal error propagation, constrained intra prediction with limited DC prediction (LDC) is used for the refreshed macroblocks, which has also been adopted by the mobile profile of Chinese audio video standard (AVS) in Mar. 2009. In addition, the reference of inter predicted frame which behinds an intra refreshed frame is limited. Experimental results on JM15.1 show that compared with traditional methods, the proposed method can achieve a considerable gain on objective peak signal noise ratio (PSNR) about 0.5 to 1.5 dB, and the subjective visual quality of reconstructed videos can also be obviously improved.