摘 要：针对高效率视频编码（High Efficiency Video Coding，HEVC）在编码过程中的帧层比特分配未考虑视频内容特性与缓冲区的状态而导致帧层比特分配不合理及编码性能低等问题，本文提出一种基于R-λ 模型的帧层码率控制优化算法。首先，通过计算得到一种度量帧层图像复杂度的综合因子，并作为新帧层比特分配权重；其次，根据目标缓冲级与缓冲区剩余比特计算出缓冲区反馈比特；最后，根据计算获得的新帧层比特分配权重和缓冲区反馈比特对帧层进行比特分配。本文算法在HM16.0 上进行了实现和性能测试，结果表明，与HEVC 原始的码率控制算法相比，优化算法的码率控制误差平均下降了2.008%，峰值信噪比平均提高了0.21dB。
关键词：高效率视频编码；码率控制；R-λ 模型；综合因子；缓冲区反馈比特
中图分类号：TN919.81 文献标识码：A 文章编号：2096-4706（2018）12-0059-03
Frame Level Rate Control Optimization Algorithm Based on R-λ Model inHigh Efficiency Video Coding
ZHENG Qiuju1，XU He2
（1.College of Mobile Telecommunications，Chongqing University of Posts and Telecommunications，Chongqing 401520，China；2.School of Communication and Information Engineering，Chongqing University of Posts and Telecommunications，Chongqing401520，China）
Abstract：Aiming at the problems of unreasonable frame layer bit allocation and low coding performance caused by theabsence of video content characteristics and buf fer state in frame layer bit allocation of high ef ficiency video coding （HEVC），this paper proposes a frame layer rate control optimization algorithm based on R-lambda model. Firstly，a comprehensivefactor to measure the complexity of the frame layer image is calculated and used as the new frame layer bit allocation weight.Secondly，the buffer feedback bit is calculated according to the target buffer level and the residual bit of the buffer. Finally，thenew frame layer bit allocation weight and the buffer feedback bit are calculated to advance the frame layer. Row bit allocation.The algorithm is implemented and tested on HM16.0. The results show that the rate control error of the optimized algorithm isreduced by 2.008% and the peak signal-to-noise ratio is increased by 0.21dB on average compared with the original rate controlalgorithm of HEVC.
Keywords：high efficiency video coding；rate control；R-lambda model；synthesis factor；buffer feedback bit
参考文献：
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作者简介：郑秋菊（1987.08-），女，汉族，重庆合川人，教师，讲师，硕士研究生，研究方向：多媒体通信。