Efficient motion estimation using two-phase algorithm

This work introduces a fast block-based motion estimation algorithm named two-phase motion estimation algorithm (TPMEA). The idea of the algorithm is to divide motion estimation procedure into two-phase: in the first phase, the sum of pixels in a line (or a column) is used as the 1D vector; In the second phase, a filtering threshold is deduced from the 1D vector matching, as Minkowski inequality has shown, blocks cannot match well if their corresponding 1D vector do not match well. Hence, the expensive 2D block matching need only be performed in a limited scope, which saves a lot of time. Moreover, an efficient implementation to calculate 1D vector is presented to speed up encoder further. From the experiment conducted in the test model of H.264(version:JM61d), the algorithm presented in This work can save approximately 30% of the time compared with the exhaustive search algorithm and achieve the same image quality. It can satisfy the demand for high performance and real-time video encoding.