Adapting to the structure of 2-D H-Transform, this paper proposes a novel wavelet domain half-pixel motion compensation algorithm HMRME (Half-pixel Multi-Resolution Motion Estimation). The primary objective of this study is the reduction of the aliasing effect caused by the down-sampling in the wavelet transform under the complexity constraints. The conventional multi-resolution motion estimation scheme can be combined with the half-pixel interpolation method to generate a new high-performance wavelet video codec. The preliminary results show that the performance of HMRME rises above its counterparts, the Multi-Resolution Motion Estimation (MRME) and the Adaptive Multi-Resolution Motion Estimation (AMRME).

In this paper, a new Hierarchical Sum of Double Difference metric, HSDD, is introduced. It is shown, as opposed to conventional Sum of Absolute Difference (SAD) metric, how this zerotree coding aware metric can jointly constrain the motion vector searching for both temporal and spatial (quad-tree) directions under multiresolution motion estimation framework. The reward from the temporal-spatial co-optimization concept of HSDD is that fewer bits are spent later for describing the isolated zeros. The embedded wavelet video coder using HSDD metric was tested with a set of video sequences and the compression performance seems to be promising.