An error detection and concealment scheme for H.264 video transmission

For entropy-coded H.264 video frames, a transmission error in a codeword will not only affect the underlying codeword but also may affect subsequent codewords, resulting in a great degradation of the received video frames. In this study, at the decoder, transmission errors within a slice in an H.264 video frame are detected by using a set of error checking conditions. For a corrupted macroblock in the first intra-coded I frame, the MB type of each corrupted macroblock is set to the intra4x4 mode. The 16 IntraPred modes of the 16 4x4 sub-blocks of the corrupted macroblock are estimated by the correct or concealed IntraPred modes of the spatially neighboring 4x4 sub-blocks, which are used to initially conceal the 16 sub-blocks of the corrupted macroblock using Intra prediction. Then, the initially-concealed macroblock is processed by the modified spatial antisotropic diffusion (SD) algorithm [8]. For a corrupted macroblock in a non-first I frame in the same scene, the corrupted macroblock is concealed by the motion-compensated best neighborhood matching (BNM) algorithm [8]. For a corrupted macroblock in an inter-coded P frame, its motion vectors are estimated by using either the corresponding "predictive" macroblocks in the previous frame or the "believable" 8-connectd neighboring macroblocks of the corrupted macroblock, and then the corrupted macroblock is concealed by the motion-compensated BNM algorithm.