Lossless VLSI oriented full computation reusing algorithm for H.264/AVC fractional motion estimation

Fractional Motion Estimation (FME) is an advanced feature adopted in H.264/AVC video compression standard with quarter-pixel accuracy. Although FME could gain considerably higher encoding efficiency, sub-pixel interpolation and sum of absolute transformed difference (SATD) computation, as main parts of FME, increase the computation complexity a lot. To reduce the complexity of FME, this paper proposes a full computation reusable VLSI oriented algorithm. Through exploiting the similarity among motion vectors (MVs) of partitions in the same macroblock (MB), temporary computation results can be fully reused. Furthermore, a simple and effective searching method is adopted to make the proposed method more suitable for VLSI implementation. Experiment results show that up to 80 add operations and 85 internal reference frame memory access operations are saved without any degradation in the coding quality.