基于前向纠错的自适应低延时传输机制  

Adaptive Low-Latency Transmission Mechanism Based on Forward Error Correction

作　　者：张森林 蔡甘霖 黄发仁 ZHANG Senlin;CAI Ganlin;HUANG Faren(College of Advanced Manufacturing,Fuzhou University,Fuzhou 350000,China;College of Physics and Information Engineering,Fuzhou University,Fuzhou 350000,China)

机构地区：[1]福州大学先进制造学院,福建福州350000 [2]福州大学物理与信息工程学院,福建福州350000

出　　处：《电视技术》2024年第1期89-92,共4页Video Engineering

摘　　要：针对无线网络中视频传输的延时以及用户数据报协议(User Datagram Protocol,UDP)因丢包造成的视频质量大幅下降问题,提出一种基于前向纠错的自适应低延时(Adaptive Low-Latency Forward Error Correction,AL-FEC)传输机制。该机制通过前向纠错方案避免在使用UDP协议传输过程中因丢包而造成的视频失真卡顿现象,通过发包策略及自适应冗余度达到降低端到端时延并提高视频传输质量的目的。根据当前的网络状况以及视频帧特性确定需要发送的源包个数,利用接收包接收到的数据包信息实时估计网络状况,从而根据网络波动情况动态更新冗余包比例。大量实验结果表明,相较于静态的前向纠错机制,AL-FEC能够使得平均端到端时延降低40~50 ms,在高丢包率情况下,视频的峰值信噪比(Peak Signal to Noise Ratio,PSNR)提高5~8 dB。In view of the delay of video transmission in wireless networks and the significant degradation of video quality caused by User Datagram Protocol(UDP)packet loss,an Adaptive Low-Latency Forward Error Correction(AL-FEC)transmission mechanism is proposed.This mechanism uses forward error correction scheme to avoid the phenomenon of video distortion caused by packet loss in the process of UDP transmission,and uses packet sending strategy and adaptive redundancy to reduce end-to-end delay and improve video transmission quality.First,determine the number of source packets to be sent according to the current network conditions and video frame characteristics.Then,the data packet informationr eceived by the receiving packet is used to estimate the netwokr condition in real time,and the redundant packet proportion is dynamically updated according to the network fluctuation.A large number of experimental results show that compared with the static forward error correction mechanism,AL-FEC can reduce the average endt-oend delay by 40~50 ms,and increase the Peak Signal to Noise Ratio(PSNR)by 5~8 dB under the condition of high packet loss rate.

关 键 词：传输机制 低延时 自适应 前向纠错 

分 类 号：TN919.72[电子电信—通信与信息系统]