Error concealment for motion-compensated interpolation
Motion-compensated interpolation is usually employed at the receiver end in order to improve the quality of the video, when a low-bit-rate video is encoded in conjunction with frame dropping. The authors propose a scheme that can exploit the block-based motion vector field available at the decoder to avoid the complex motion estimation. The scheme is based on an iterative refinement technique that employs the finite-element method to efficiently conceal the interpolation errors caused by unfilled holes or overlapped pixels in the predicted frames. As a consequence, no pixel classification is needed in the proposed scheme, thus reducing substantially the computational complexity. The scheme is capable of concealing the errors in the homogeneous regions as well as in regions containing sharp edges. The proposed scheme is simulated with the original frames of a number of test sequences, as well as implemented with the H.264/AVC decoded frames. The results from these extensive simulations show that the proposed scheme results in reconstructed frames having a better visual quality and a lower computational complexity than the existing schemes.