新一代视频编码标准H.266/VVC(Versatile Video Coding)的码率控制算法采用编码参数相互独立的率失真优化技术。然而,同一帧内的编码树单元(CTU)间在空域上相互影响,且存在全局编码参数;同时,CTU级比特分配公式采用近似的编码参数分配比...新一代视频编码标准H.266/VVC(Versatile Video Coding)的码率控制算法采用编码参数相互独立的率失真优化技术。然而,同一帧内的编码树单元(CTU)间在空域上相互影响,且存在全局编码参数;同时,CTU级比特分配公式采用近似的编码参数分配比特,进而降低了码率控制精度和编码性能。针对上述问题,提出空域全局优化CTU级比特分配算法RTE_RC(Rate Control with Recursive Taylor Expansion),并通过递归算法逼近全局编码参数。首先,建立空域全局优化比特分配模型;其次,应用递归算法求解CTU级比特分配模型中的全局拉格朗日乘子;最后,优化编码单元的比特分配并对编码单位进行编码。实验结果表明,在低延时P(Prediction)帧(LDP)配置下,与码率控制算法VTM_RC相比,所提算法的码率控制误差由0.46%下降至0.02%,码率节省了2.48个百分点,编码时间下降了3.52%,显著提升了码率控制精度和率失真性能。展开更多
Turbo decoding is iterative decoding, and the MAP algorithm isoptimal in terms of performance in Turbo decoding. The log-MAPalgorithms is the MAP executed in the logarithmic domain, so it isalso optimal. Both the MAP ...Turbo decoding is iterative decoding, and the MAP algorithm isoptimal in terms of performance in Turbo decoding. The log-MAPalgorithms is the MAP executed in the logarithmic domain, so it isalso optimal. Both the MAP and the log-MAP algorithm are complicatedfor implementation. The max-log MAP algorithm is de- Rived from thelog-MAP with approximation, which is simply compared with the log-MAPalgorithm but is subopti- Malin terms of performance. A modifiedmax-log-MAP algorithm is presented in this paper, based on the TaylorSeries of logarithm and exponent. Analysis and simulation resultsshow that modified max-log-MAP algorithm Outperforms the max-log-MAPalgorithm with almost the same complexity.展开更多
文摘新一代视频编码标准H.266/VVC(Versatile Video Coding)的码率控制算法采用编码参数相互独立的率失真优化技术。然而,同一帧内的编码树单元(CTU)间在空域上相互影响,且存在全局编码参数;同时,CTU级比特分配公式采用近似的编码参数分配比特,进而降低了码率控制精度和编码性能。针对上述问题,提出空域全局优化CTU级比特分配算法RTE_RC(Rate Control with Recursive Taylor Expansion),并通过递归算法逼近全局编码参数。首先,建立空域全局优化比特分配模型;其次,应用递归算法求解CTU级比特分配模型中的全局拉格朗日乘子;最后,优化编码单元的比特分配并对编码单位进行编码。实验结果表明,在低延时P(Prediction)帧(LDP)配置下,与码率控制算法VTM_RC相比,所提算法的码率控制误差由0.46%下降至0.02%,码率节省了2.48个百分点,编码时间下降了3.52%,显著提升了码率控制精度和率失真性能。
文摘Turbo decoding is iterative decoding, and the MAP algorithm isoptimal in terms of performance in Turbo decoding. The log-MAPalgorithms is the MAP executed in the logarithmic domain, so it isalso optimal. Both the MAP and the log-MAP algorithm are complicatedfor implementation. The max-log MAP algorithm is de- Rived from thelog-MAP with approximation, which is simply compared with the log-MAPalgorithm but is subopti- Malin terms of performance. A modifiedmax-log-MAP algorithm is presented in this paper, based on the TaylorSeries of logarithm and exponent. Analysis and simulation resultsshow that modified max-log-MAP algorithm Outperforms the max-log-MAPalgorithm with almost the same complexity.
