A new unit layer linear rate control algorithm for H.264 based on PID controller

Abstract This paper presents a new unit layer rate control algorithm for H.264 combining PID controller with linear rate model. In various video coding standards, like MPEG-2, H.263, MPEG-4 and H. 264, it has been reported that the linear rate control algorithm can achieve more accurate and robust rate control. In fact, human is not only sensitive to spatial quality, but also to temporal quality. In order to have better tradeoff between spatial and temporal quality and obtain more consistent quality, the PID controller is inducted into unit layer linear rate control algorithm for H. 264. The scene changes are also effectively dealt with. Experimental results show that the proposed rate control algorithm can not only track target bit rate more accurately and achieve significantly smaller bit rate estimation error, like that of linear rate control algorithm, but also improve the temporal quality while keeping high spatial quality, and the quality of frames with scene changes can obviously be improved.