Quick algorithm for fractional-pixel accurate motion estimation
Kun Tang · Journal of Tsinghua University(Science and Technology) · 2007
The computations for fractional-pixel motion estimates in video coding standard H.264 are reduced by an algorithm based on the characteristics of the integer pixel and fractional-pixel motion vectors.An array of early termination thresholds is used to skip most of the unnecessary fractional-pixel motion search points,with the computational cost further reduced with the diamond search method.Tests show that with the early termination algorithm,the computations for the fractional-pixel motion estimates are reduced by 77.45%,with a PSNR(peak signal noise ratio) loss of 0.03 dB and a bit rate increment of 2.38%.The algorithm significantly reduces the computation cost of motion estimates,while maintaining encoder performance.The algorithm is most effective for sequences with simple movements and constant backgrounds.