Hardware architecture for global motion estimation for MPEG-4 Advanced Simple Profile

Global motion estimation and compensation (GME/GMC) is a new and important coding tool in MPEG-4 Advanced Simple Profile (ASP). The coding gain of GME/GMC is 1-1.6 dB compared to that without GMC. However, because of the irregular memory access and huge memory bandwidth of GME/GMC, few hardware architectures have been proposed. In this paper, we proposed an algorithm which can save 87.27% memory bandwidth compared to that of the original algorithm. By the proposed arrangement of memory, the impact of the irregular memory access is reduced, and four neighboring pixels, which are used for the interpolation of GMC, can be accessed in one cycle. Finally, we also proposed a hardware architecture for GME in MPEG-4 ASP@L5. The total gate count is 131 K, at 100 MHz and the internal memory size is about 10.8 Kb. It is reasonable to be integrated into MPEG-4 ASP encoders.