Rate-distortion performance of dual-layer motion compensation employing different mesh densities

We describe a dual layer algorithm for mesh-based motion estimation. The proposed algorithm, employing meshes at different scales, aims to improve the rate-distortion performance at fixed bit rates. Without the need for time-consuming evaluation, the proposed algorithm identifies the motion-active regions in a picture. By enhancing the mesh structure in the aforementioned regions, a significant improvement in motion estimation is evident. Furthermore, the scheme to construct two different significance maps at both encoder and decoder provides a reduction in transmission overhead. Simulations on test sequences possessing high motion activity show that the proposed algorithm results in a better PSNR-rate performance compared to single layer motion estimation using 16×16 triangular meshes. Improvements of up to 1.6dB are obtained.