An Efficient Hardware Architecture for Full-Search Variable Block Size Motion Estimation in H.264/AVC

In this paper, we propose a high speed hardware architecture for the implementation of full-search variable block size motion estimation (VBSME) suitable for high quality video compression. In the high-quality video with large frame size and search range, the memory bandwidth is mainly responsible for throughput limitations and power consumption in VBSME. The proposed architecture is designed for reducing the memory bandwidth by adopting "meander”-like scan for a high overlapped data of the search area and using on-chip memory to reuse the overlapped data. We can reuse the previous candidate block of 94% to the current one and save about 23% memory access cycles in a search range of [-16, +15]. The architecture has been prototyped in Verilog HDL, simulated by ModelSim and synthesized by Synopsys Design Compiler with Samsung 0.18um standard cell library. Under a clock frequency of 51MHz, The simulation result shows that the architecture can achieve the real-time processing of 720x576 picture size at 30fps with the search range of [-16~+15].