Abstract
In this paper, a novel error concealment algorithm is proposed for the MPEG-4 video decoding. The MPEG-4 standard adopts a set of error resilient tools to improve video robustness in error-prone environments such as wireless communication. Error concealment scheme can improve image quality for images with the residual errors which are not corrected although applying the error resilient tools. However, since error concealment technique is not specified in the MPEG-4, there are strong demands to develop novel high performance error concealment technique. The problem for conventional error concealment algorithms is high computational complexity or a low performance for video sequences with high motion. The proposed algorithm adopts a hybrid scheme, which can achieve consistent performance for various video sequences at various error rates, and can reduce computational complexity using the temporal and spatial correlation of macroblocks. This hybrid scheme is composed of two techniques; the modified DMVE technique and adaptive spatial searching technique. The modified DMVE technique reduces the computational cost by using the temporal and spatial correlation of motion vectors, and adaptive spatial searching technique can conceal high frequency components by searching for similar pixels within a frame. The proposed algorithm is constructed on the basis of the MPEG-4 software decoder, and the experimental results demonstrate that our approach provides acceptable performance both subjectively and objectively at various bit error rates.
