The MPEG-2 compression algorithm is very sensitive to channel disturbances
due to the use of variable-length coding. A single bit error during transmi
ssion leads to noticeable degradation of the decoded sequence quality, in t
hat part or an entire slice information is lost until the nest resynchroniz
ation point is reached, Error concealment (EC) methods, implemented at the
decoder side, present one way of dealing with this problem. An error-concea
lment scheme that is based on block-matching principles and spatio-temporal
video redundancy is presented in this paper. Spatial information (for the
first frame of the sequence or the nest scene) or temporal information (for
the other frames) is used to reconstruct the corrupted regions. The concea
lment strategy is embedded in the MPEG-2 decoder model in such a way that e
rror concealment is applied after entire frame decoding. Its performance pr
oves to be satisfactory for packet error rates (PER) ranging from 1% to 10%
and for video sequences with different content and motion and surpasses th
at of other EC methods under study.