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A New Multi-Mode Intra-Frame Error Concealment Algorithm for H.264/AVC

In video communications over error-prone environments, compressed video is fragile to transmission errors. The decoder side error concealment (EC) is an efficient way to recover a damaged video sequence. Typically traditional video EC algorithms for H.264/AVC intra-frames operate in macroblock (MB) level and they offer a single concealment mode for all frames regardless of frame features. This paper proposes a new multi-mode error concealment (MMEC) algorithm for intra-frames of H.264/AVC. The proposed algorithm provides several different EC modes so that the decoder is able to choose the best modes to conceal errors. By applying the proposed method, a MB can be partitioned into smaller 8 times 8 subblocks, each subblock can be recovered using available temporal or spatial information based on the MB characteristics. If there are any subblocks recovered by using temporal information, these subblocks will be further used for directional spatial EC for the rest subblocks. The proposed new MMEC algorithm has been evaluated and compared with the H.264/AVC reference implementation and two other classical EC algorithms. The experimental results show that the proposed MMEC algorithm can achieve up to 5 dB gains in PSNR therefore significantly improves the video quality.