Spatial and temporal adaptive error concealment algorithm for MPEG-2

In this paper, an adaptive error concealment (AEC) algorithm is presented for MPEG-2 video streams. For the I -pictures in the sequence, the criterion for the decision between spatial and temporal methods is based on a measurement of the image activity. Since the motion vectors (MVs) above and below are very different in magnitude and direction from each other in P- and B-pictures, the proposed error concealment (EC) program is performed in three stages: The first stage is to split a missing MB into two sub-MBs. The second stage is to estimate the coding mode of the two sub-MBs from the mode of the top and bottom MBs of the lost MB. The next stage, based on the estimated coding mode, is to conceal the two sub-MBs separately. The experimental results showed that when the bit error rate (BER) of several video sequences were 1.2×10^-5, the PSNR-values for the proposed AEC method were approximately 2-3 dB over the PSNR-values for the conventional methods.