Multi-hypothesis-Based Error Concealment for Whole Frame Loss in HEVC.

In video transmissions over wired and wireless networks, packet losses occurs frequently due to channel errors and/or network latency, which may result in the whole video frame losses and severe video quality degradation. To address this problem, many error concealment algorithms have been proposed in order to reduce the effect of channel errors. However, most of these algorithms only focus on concealment of a missing block rather than a missing frame, which is far more difficult than the former since intra-frame information are no longer available in concealing the error. In this paper, we propose a practical multi-hypothesis based error concealment algorithm to recover the whole missing frame. This algorithm first reconstructs a motion vector field for each coding tree unit in the lost video frame according to the motion vector relationship between adjacent coding unit levels, and then the lost frame is reconstructed based on the theory of multi-hypothesis using each motion vector in the reconstructed motion vector field. The experimental results show that the proposed algorithm can effectively reconstruct the lost frames and significantly improve the video quality under frame loss.