基于相邻帧相关性的帧间宏块模式选择算法

H．264/AVC 在帧间运动估计/补偿编码过程中定义了7种帧间编码模式,并采用率失真优化全遍历策略来选择最优模式,这使计算复杂度急剧增加．针对这一问题,阐明了需对如何准确、快速地对块预测模式做出选择进行相关的研究．并就利用自然图像序列中相邻帧所表现出的强相关性提出了一种快速的帧间编码模式选择算法,通过计算部分编码模式来减少计算的复杂性．实验结果表明,该方法平均节省时间约18%,比特率平均下降约0．02%,而 PSNR 平均仅仅降低0．02dB．

Inter mode decision algorithm based on the relativity of the adjacent frames

There are seven block sizes used for inter-frame motion estimation/compensation for H.264/AVC.However,this feature requires the encoder to compute the rate-distortion cost for every available block mode.As a result,the complexity and com- putation load of video coding increase drastically.New techniques for efficient and fast selection of the variable block modes have been developed to reduce the computational complexity.In this paper,a fast inter mode decision method for H.264 coding standard was presented,which was based on the strong relativity of the adjacent frames in natural video.The method took a part of modes to reduce the complexity.Experimental results show that the proposed method can achieve a reduction of 18% encoding time on aver- age,with a mere 0.02% bit rate decrease and a negligible average PSNR loss of only about 0.02dB.