A High Throughput Diamond Search Architecture with Shift Mechanism for 720p Motion Estimation

The paper implements a shift based diamond search architecture, for HDTV videos. High resolution frames like 720p need large memory to store the pixel data. This large pixel data is stored on an external memory and an internal local memory is updated with the pixel data on the reference frame and current frame required for particular diamond search iterations. This is done as internal memory is expensive. However, accessing pixel data from external memory incurs high timing latency. This paper implements a shift based DS architecture to shift data in internal local memory and update from external memory only the pixels which are new to search area. This reduces the redundant operation of accessing same pixel data for successive searches. Even when considering equal latency for internal and external memory access, when simulation was performed on the same sample 720p frame, architectures with no shift block took 173.170ms vs with shift block took 90.564ms. When considering the latency of external memory access this difference in timing becomes largely significant.