Error concealment for MPEG-2 video decoders with enhanced coding mode estimation

We present a novel error-concealment method for MPEG-2 video decoders. Imperfect transmission of block-based compressed images may result in loss of blocks, making image degradation inevitable. In the hybrid error-concealment method, both spatial and temporal error concealment repair the damaged regions through adaptive interpolation in the respective domains. In order for the hybrid method to yield good performance it should be presumed that coding-mode estimation is correct. In reality, however, erroneous coding mode estimation frequently occurs, ultimately resulting in poor performance. In the proposed method, we reduce the number of erroneously estimated coding-modes by utilizing the fact that MPEG-2 video coding is based on block-based coding. This enhanced hybrid technique effectively conceals the lost blocks by raising the probability of correct coding mode estimation by exploiting the image characteristics such as scene changes and complex motions. Through computer simulations on damaged images we show that the proposed method has excellent performance.