帧内更新是在视频编码中常采用的容错手段,它能够有效的阻止差错传播。帧内更新率高,能够有效的抑制差错扩散,但是会降低编码效率,在码率一定时,会增大信源失真。只有选择合适的更新率,才能更好的达到抗差错的目的。本文提出了一种基于端到端模型,对自适应更新和码率控制进行联合优化的算法,在满足码率的要求下,自适应的调整帧内更新位置和更新数量,实现端到端失真最小。实验结果表明,本文提出的算法与随机更新算法相比,PSNR提高了0.5~1.5dB。
Intra-update is a common error resilient technique in video coding. It could stop the error-propagated distortion, but would reduce the coding efficiency, and increase the source distortion in fixed bit rate. In Intra-update, the update rate plays a key role in effect of error control. Joint optimization of adaptive intra-update and rate control based on end-to-end distortion is proposed to choose the optimized rate. It can adaptively choose the update position and the update rate in order to get the minimal end-to-end distortion. Computer simulations in lossy channel environment are conducted to assess the performance of the proposed method.