A fast and quality-preserving method for H.264 encoding using dynamic SAD maps
Dajun Wu, Tuan Kiang Chiew, K.P. Lim, Jo Yew Tham, Zhicheng Zhou, C.C. Ko · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2007
It is well known that motion estimation is the most computationally intensive processing unit of the H.264 video encoder. Various fast motion estimation algorithms have been proposed to reduce its complexity. Generally, these approaches achieve speedup by reducing the number of candidate search points within the search window. In this paper, we propose a new method, which uses the Sum-of-Absolute-Differences mapping (SAD map) to dynamically cache the SAD values and then reuse them for different block sizes. Experimental results on standard video sequences verified that the proposed method is capable of increasing the encoder speed by up to 15% without any loss in PSNR value or increase in bit rate. Due to its generic nature, this method can be applied in any fast motion estimation methods although it is especially effective in the full search motion estimation method.