非对称无线传输信道的音视频同步优化设计  

Design of Audio and Video Synchronization Algorithm for Asymmetric Wireless Transmission

作　　者：马宏雷[1] 刘儿兀[2] 朱军[1] 

机构地区：[1]中科院上海微系统与信息技术研究所,上海200050 [2]同济大学电子与信息工程学院,上海201804

出　　处：《计算机仿真》2016年第2期221-226,479,共7页Computer Simulation

基　　金：国家重大科技专项(2009ZX03006-003);国家重大科技专项(2009ZX03006-004)

摘　　要：在非对称无线传输信道环境中。由于信道和带宽的限制,传输信道上下行不对称,造成上行信道传输音视频等大量数据信息,而下行信道仅仅传输一些指令信息。传统的算法因没有考虑均衡性要求,导致下行指令发送与上行音视频等数据传输不同步。提出采用时间戳的音视频同步算法,无需及时反馈接收端同步状态。在发送端获取视频编码器视频输出时的时间戳,建立参考时钟轴,并形成参考时钟,连同音频和视频流各自的解码时间戳封装到音视频复合流中,通过无线信道发给接收端。接收端重构参考时钟轴,并结合各自的解码时间戳(DTS)实现音视频同步播放。最后分别对参考时钟轴的准确性、音视频的同步性和网络传输性能做了试验。试验结果表明由于显示时间戳(PTS)采用了估算的方法,为视频B帧与音频帧同步性能的提高提供了依据。An audio and video synchronization algorithm for asymmetric wireless transmission channel environment is presented based on the time stamp. The sender obtain the timestamp of the output of the video,video encoder establishes the reference clock axis,and form the reference clock; the reference clock along with respective decoding time stamps of audio and video streams is encapsulated to the audio and video streams,and sent to the receiver via wireless channel. The receiver reconstructs the reference clock axis,and combines with their respective decoding time stamp（ DTS） to implement audio and video synchronization. Finally the accuracy of the reference clock axis,the synchronization of audio and video,and the performance of network transmission are tested,respectively. Test results show that the estimation method is adopted for the display time stamp（ PTS）,some video B frame may be out of synchronization with the audio frame,but the basic resolution is not to come out on the senses.

关 键 词：音视频同步 解码时间戳 无线信道 参考时钟 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]