H.264/AVC Fast Macroblock Mode Decision Algorithm
Ji-Woong Kim, Yong-Kwan Kim · Journal of the Institute of Electronics Engineers of Korea · 2007
For the improvement of coding efficiency, the H.264/AVC video coding standard employs new coding tools compared with existing coding standards. However, due to these new coding tools, the complexity of K264/AVC standard encoder is greatly increased. Specifically, the inter/intra mode decision method using RDO(rate-distortion optimization) technique is one of the most complex parts in H.264/AVC. In this paper, we focus on the complexity reduction in macroblock mode decision. In the proposed method, we reduce the complexity of the mode decision process using simple square filters, and using spatial block correlation method. Additionally, exploiting the best mode of sub_macroblock in mode, we proposed an algorithm to eliminate some intra modes in current macroblock mode decision process. In addition, we employed a method to raise the probability to select SKIP, , and modes which usually show low complexity and low bitrate compared with other modes. From the simulation results, the proposed algorithm reduce the encoding time by maximum 83% of total, and reduce the bitrate of the overall sequences by on the average compared with existing coding methods.