为了适应网络的时变性,提高传输的可靠性同时满足实时性,提出一种新的的网络传输结构——RTP/SCTP/IP。系统采用基于H.264协议的精简PFGS编码结构,利用SCTP协议的多流特性,将PFGS流分成多个子流分别传输,给出了一种基于网络带宽预测的传输方法。仿真试验表明,该方法较传统网络结构RTP/UDP/IP而言,传输的可靠性和网络适应能力有了很大提高,图像平均PSNR比传统的RTP/UDP/IP网络结构下的PSNR高0.5dB~1.5dB。
A new transport framework of RTP/SCTP/IP is presented for adapting to the time-variable Intemet and enhancing the reliability of transport. An improved simplified PFGS coding framework, using the standard of H.264 in base layer of PFGS, is adopted on source terminal. The steam of PFGS is separated for many sub-flows to transport by the characteristics of SCTP multi-streaming for improving the reliability and flexibility of transmission. A transport method that is a finite state machine(FSM) framework based on network bandwidth prediction over the Internet is presented. Simulation results show that this scheme can highly improve the quality of video and obtain a gain of about 0.5dB-1.5 dB in PSNR compared with the traditional network framework. Ability of adapting to network and reliability of transmission are improved rapidly.