基于运动检测的H.264码率控制的算法

针对H.264/AVC 经典流控算法JVT-G012对运动剧烈图像流控效率的不足，提出了一种基于图像运动剧烈程度的流控算法。对运动剧烈的图像，在同一复杂度区域内，用前一帧实际编码码率与目标码率的差值调整当前帧目标码率，并且编码时利用最小率失真模式的原始帧和重建帧的SAD估计MAD值，根据二次模型估计量化参数优化拉格朗日参数。仿真试验证明与JVT-G012以及Jiang等对H.264AVC的改进的码率控制算法相比，在运动剧烈或者场景切换时，虽然码率比JVT-G012略有增加但低于Jiang等的改进算法，并且变化剧烈的视频帧图像信噪比有明显的增加，平均信噪比也得到了提高。

Novel bit-rate control algorithm for H.264 based on motion detection

This paper aimed at the rate control problems of JVT-G012, the typical algorithm for H.264/AVC, and presented a new rate control algorithm. After motion detection, if the previous and current frame were in the same complex area, factual encode rate of the previous frame was used to adjust target rate of the current frame. As for the scene changes and high motion video based on motion detection, the minimum sum of squared difference between original and reconstructed pixels after the rate distortion option was used to estimate MAD, and then, MAD was used to compute quantization parameter based on the quadratic model in the process of encoding. The Lagrange parameter can be optimized. The experimental results show that the rate of this algorithm is higher than JVT-G012 and lower than Improvement of H.264AVC by JIANG but the scheme of this paper can effectively improve video quality at scene changes and high motions. Moreover, the scheme also enhances the average PSNR of the test sequences compared to JVT-G012 and JIANG's Improvement.