We discuss an error concealment algorithm for moving picture coding in error-prone mobile communication networks. MPEG-4 standard provides not only high compression capability but also error resilient functionality for transmission channels with bit errors. In the decoder, though error concealments are carried out on parts of an image not decoded due to code bit errors, its concealment methods affect, on a large scale, the quality of a decoded image. In this paper, we propose a new error concealment algorithm that is based on the motion estimation method using boundary pixel values of an error block in a current frame and then replaces error blocks with similar blocks searched in the previous frame. In conventional methods, since motion vectors are not used for error concealment, correct reconstruction is sometimes not attained. However, by the proposed method it is possible to provide more ideal results. Moreover, simulation results demonstrate that the quality of a recovered image is significantly improved.
展开▼
