Correction of random and outburst error in MPEG-2 code

Due to the use of variable length coding(VLC), the MPEG-2 code is very sensitive to channel disturbances. A single bit error in I frame may propagate up to the rest of the slice until the next resynchronization point is reached and may also propagate into temporal domain because of inter-frame coding. As a result, it leads to noticeable degradation of the decoded video quality. To prevent error propagation, an error correction algorithm to I frame is presented in this paper:moving window error correction algorithm. Be different from error concealment (EC) methods, it can partly correct some random and outburst errors in the corrupted discrete cosine transform (DCT) regions and can recover the original information. EC methods are used only when the correction algorithm fails. The performance of the proposed scheme proves to be satisfactory and surpasses the only use of EC methods under study.