一种改进的H.264帧层码率控制算法

针对H.264码率控制算法在缓冲区控制上的不足,提出一种改进的帧层码率控制算法.对缓冲区进行监视,根据已编码帧实际缓冲与目标缓冲占用率的情况进行量化参数的调整.当实际缓冲偏离目标缓冲较大时,适当增大或者减小量化参数,使编码后实际缓冲更接近目标缓冲,防止缓冲发生上溢或下溢.仿真结果表明,对于纹理简单的序列,改进的算法在PSNR几乎不变的情况下,得到了更精确的码率控制,实际缓冲更接近目标缓冲,缓冲区占有率更稳定.

An improved rate control algorithm of frame layer for H.264

For the shortage of the buffer control for H. 264 rate control algorithm, an improved frame layer rate control algorithm is proposed. First monitoring the buffer occupancy, then adjust quantization parameter based on the situation of actual buffer and the target buffer occupancy of encoded frame. When the actual buffer deviating from the target buffer large, appropriate increase or reduce the quantization parameter, make the actual buffer closer to the target buffer, therefore prevent buffer overflow or underflow. Simulation results show the PSNR of new algorithm is almost constant, the actual buffer is closer to the target buffer, and more steady.