针对JVT-H017提案码率控制算法初始量化参数选择与视频内容无关的问题,在总结现有改进算法基础上,提出一种快速有效的初始量化参数选择算法。该算法只需第一个P帧的平均绝对误差(MAD)值及每像素平均比特率信息即可快速给出初始量化参数。实验结果表明,在恒定比特率下,所提算法与JVT—H017算法相比,预测的初始量化参数更加准确,APSNR最大能提高1.1dB,并且算法对含B帧编码结构同样有效。
As for the problem that initial Quantization Parameter (QP) selection of rate control in JVT-H017 has nothing to do with the video content, this paper analyzed the existing improved algorithms and puts forward a fast and effective initial quantization parameter selection algorithm. After obtaining the Mean Absolute Difference (MAD) of the first P frame and average bits per pixel, the proposed algorithm can calculate an appropriate initial quantization parameter. The experimental results show that compared with JVT-H017 under constant bit rate, the predicted initial quantization parameter is more accurate, and greatly improves the performance of rate control. The maximum performance gain in APSNR is up to 1.1 dB and works well when it contains the B frames.