A robust video encoding scheme to enhance error concealment of intra frames

In this paper a robust encoding scheme is proposed to improve the visual quality of HEVC decoded video when intra frames are lost along the streaming path. For this purpose, the encoding process includes frame loss simulation and subsequent error concealment, to find the most efficient method that should be used by a decoder to recover lost intra frames. In this novel scheme, each image is divided into partitions, which are associated with the error concealment method that achieves the lowest distortion. Then this information is signalled to the decoder through SEI messages in the coded stream. In order to efficiently use the signalling overhead, rate-distortion optimisation is used to achieve the best trade-off between the number of transmitted symbols and distortion of reconstructed frames. Experimental results show the effectiveness of the proposed method to enhance the quality of reconstructed intra frames under different packet loss ratios (PLR). For PLR=10%, the robust coding scheme is able to improve the average PSNR of all frames affected by errors, up to 1.50 dB and 3.44 dB in Low-Delay and Random-Access configurations respectively, at a maximum overhead cost of 0.24%.