An Improved Error Concealment Scheme for Entire Frame Loss of H.264/AVC

In this paper, we develop an improved error concealment scheme for entire frame loss of H.264/AVC by using variable-size block motion vector extrapolation. At first, the proposed algorithm extrapolates MVs from available neighboring frames onto the lost frame and determines the MV of each 8x8 block, for those blocks with dissimilar candidate MVs, they are divided into four sub-blocks and an re-estimation method is implemented on every sub-blocks. Then, a more complete motion vector field is obtained by using median filtering. At last, the blocks without extrapolation MVs are concealed by using linear interpolation algorithm. Experimental results show that this method can alleviate the shortcomings of the fixed-size method effectively and provide better performance than other concealment methods.