良好的码率控制对视频信号的编码与传输有重要的影响;基于待编码帧的复杂度和缓冲区状态,提出了一种新型的H.264码率控制初始化方法;第一个I帧和P帧首先进行预编码,以修正第一个I帧的比特分配;根据I帧的图像复杂度建立新型I帧码率-量化参数(R-Q)模型,根据该模型,第一编码帧的量化参数得以确定；仿真结果证明,该初始化方法可以有效提高重建视频的峰值信噪比(PSNR),对实验所用QCIF序列,平均PSNR提高了0.86dB,同时大幅减少了跳帧情况的发生.%Rate control (RC) plays an important role in video coding and transmission. In this paper, we present a novel rate control initialization algorithm for H. 264 by taking image complexity, buffer status into consideration. The first I frame and P frame of video sequence are encoded using the algorithm JVT-G012, and the number of target bits for the first frame is corrected. Using the spatial complexity of I frames, a new R-Q model is established. And based on the R- Q model, the initial quantization parameter is calculated. Experimental results show that, the proposed algorithm can increase the average peak signal-to-noise (PSNR) ratio of reconstructed video by 0. 86 dB and some skipped frames are avoided.
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