Low-complexity block-based motion estimation algorithm using adaptive search range adjustment

We propose an adaptive search range adjustment algorithm that is particularly suitable for low-bit-depth motion estimation approaches. Typical low-bit-depth motion estimation approaches, such as one-bit transform (1BT), two-bit transform (2BT), and truncated gray-coded bit-plane matching (TGCBM), perform a full search with low-bit expression. We propose combining a search-range adjustment, which can be predicted by using motion vector information of the reference frame and the existing bit-wise matching methods, such as 1BT, 2BT, and TGCBM. Combining this proposed algorithm and low-bit expression enhances both motion estimation accuracy and time consumption. Experimental results show that low-bit-depth motion estimation approaches using this proposed algorithm have an outstanding performance compared with those without the proposed algorithm both in motion estimation accuracy and time consumption. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.OE.51.6.067010]