【摘要】 为了更好地保证流媒体系统实时约束下的同步性能,解决流媒体缓冲区设置中同步与播放时延的矛盾,使缓冲区长度设置在实时性约束下最大化,在实时环境条件下,给出了一种缓冲区占用水平设定值的动态确定方法,在仿真实验中以此作为流媒体速率控制系统的设定值.为了克服传统控制方法超调量过大的弊端,选择了最小方差控制(MVC,minimum variance control),设计了基于最小方差控制的实时流媒体缓冲区自适应设定值跟踪传输算法.仿真实验结果表明,该方法能够对不同的网络时延自适应,计算出合适的缓冲区占用水平设定值,实现了缓冲区占用水平对设定值的跟踪,播放具有良好的实时性.更多还原

【Abstract】 To guarantee the synchronization performance of a constrained real-time streaming medium system and settle the contradiction between synchronization and playback delay on the basis of buffer maximization,a dynamic method to determine the setpoint of buffer occupation was proposed and used in the simulation as the setpoint for the medium streaming rate control system. To eliminate the overshoot by way of conventional control,the MVC was chosen to design a transmission algorithm of adaptive tracing with buffer setpoint for a real-time streaming medium. Simulation results showed that the algorithm proposed can adaptively compute the proper setpoint of buffer occupation with any network delay and implement the tracing of dynamic setpoint,thus providing the playback with highly real-time performance.更多还原