摘要
流媒体业务由于业务其自身的特点,流媒体数据经网络传输时在时延、时延抖动以及带宽分配方面都有较高的要求,称之为服务质量。流媒体技术是计算机支持的协同工作CSCW的关键技术之一,另外随着Internet技术的高速发展和普及,在其应用数据流中,占据重要地位的流媒体及其传输与控制技术成为工业界以及研究领域关注的焦点。
实时传输协议(RTP)数据包中含有时间戳和序列号,为端到端或多播视频数据的传输、管理,延时、延时抖动控制以及带宽分配等提供了必要的信息。因此,研究基于RTP的Internet环境下的业务协同控制技术,以保证和提高流媒体业务的服务质量,具有一定的研究意义与实用价值。
本文在详细探讨RTP/RTCP协议和协同技术的基础上,以irtplib(RTP协议库)框架为基础,设计并实现了一个Linux平台下的视频传输与监视系统,具体包括视频预览与录放、频道选择与窗口控制、云镜控制等常规功能模块以及基于RTP/RTCP的视频传输、缓存控制和基于TFRC的拥塞控制、链路选择等具有协同特征的功能模块。最后,本文对所实现的视频监视系统进行了功能测试,结果表明系统能稳定运行,达到了预期设计要求。
Because of the specialty of stream media application, the delay, jitter and the control of bandwidth of stream media data have high requirement, and that's called QoS. Stream media technology is one of the key technology of computer supported cooperated work. As the development and popularization of Internet, data stream, its transfer and control of the internet application data stream is becoming the focus of industry and its research field.
The information of P2P and multicast video transfer, management, delay and jitter control, bandwidth distribution could been get from timestamp and sequence number included in Real-time Transport Protocol data packets. So, it has some meaning and practical value of the research of how to assure and enhance the QoS of stream media by CSCW based on RTP over Internet.
This thesis designs one video transfer and video surveillance system on jrtplib after some detailed discussion about RTP/RTCP and synergetics. There is some normal functions such like preview, record, window selection and control, plan and plit control, and there is some special functions with CSCW characteristic like transfer based RTP, buffer control, TFRC congestion control, link choose. At last, the test of the functions of the system was done, it is working properly, suffice the anticipate desire.
引文
[1] 钟玉琢,向哲,沈洪.流媒体和视频服务器[M].清华大学出版社,2003.6
[2] ITU-T. Definition of NGN, http://www.itu.int/ITU-Tngn/definition.html
[3] 龚双瑾,刘多.下一代电信网的关键技术[M].国防工业出版社,2003.10
[4] 陈建亚,余浩.软交换与下一代网络[M].北京邮电大学出版社,2003.2
[5] 赵慧玲,叶华.软交换为核心的下一代网络技术[M].人民邮电出版社,2002.8
[6] 张丽.流媒体技术大全[M].中国青年出版社,2001.6
[7] Sally Floyd, Mark Handley, Jitendra Padhye. A comparison of equation-based AIMD congestion control[EB/CL], http://www.aciri.org/tfrc/, 2000.5
[8] University College London, UCL Network and Multimedia Research Group. http://www-mice.cs.ucl.ac.uk/multimedia, 2006
[9] H.哈肯,郭治安等译.信息与自组织[M].成都:四川教育出版社,1988
[10] 史美林,向勇,伍尚广.协同科学—从协同学到CSCW.清华大学学报[J],1997,37(1):85-88
[11] Tudjarov, Boris, lgoshi. Collaborative Design Conception and Applications[C]. PROC IEEE, (USA), 1999, 6(1):Ⅵ-30-Ⅵ-35
[12] Schulzrinne, H. Casner, S. Frederick, V. Jacobson, RTP: A Transport Protocol for Real-Time Applications, RFC 3550, 2003.7
[13] An Hui. Research and Implementation of RTP [D]. Wuhan:School of Computer, Wuhan University, 2002
[14] Colin Perkins. RTP: Audio and Video for the Interenet [M], Addison Wesley, 2003.6
[15] http://research.edm.uhasselt.be/jori/jrtplib/jrtplib.html, 2007
[16] S.Floyd, JPadhye, J.Widmer, TCP Friendly Rate Control (TFRC):Protocol Specification, RFC 3448, 2004.1
[17] J. WidMer, R.Denda, M. Mauve, A Survey on TCP-Friendly Congestion Control. IEEE Network, 2001.5
[18] System SDK manual of the DS40xxHCI and DS400xMDI for linuxV4.1, 2007
[19] Draft ITU-T Recommendation and Final Draft International Standardof Joint Video Specification ITU-T Rec. H.264/ISO/IEC 14496-10AVC. In Joint Video team of ISO/IEC MPEG and ITU-T VCEG, JVT-G050, 2003
[20] W.Richard Stevens著,范建华,胥光辉,张涛等译.TCPhP详解卷1:协议[M].机械工业出版社,2000,4
[21] Rhee I, Ozdemir V, Yi Y. TEAR: TCP emulation at receivers-flow control for multimedia streaming. Technical report, NCSU IEEE INFOCOM, New York, NY, 1999, 1337-1345
[22] Widmer J, Mauve M, Damm J. Probabilistic congestion control for non-adaptable flows. In: Proc. of NOSSDAV, 2002, 13-21
[23] Rejaie R, Estrin D.RAP : An end-to-end rate-based congestion control mechanism for realtime streams in the Internet [A]. Proceedings ofIEEE INFOCOM 1999[C]. New York, USA, 1999. 1337-1345.
[24] Y. Yang and S. Lam, "General AIMD Congestion Control, " In Proceedings of ICNP 2000, Osaka, Japan, 2000.12
[25] Floyd, S. Handley, Padhye, Widmer, J. Equation Based Congestion Control for Unicast Applications SIGCOM 2000, Stockholm (Sweden), 2000.5
[26] Padye, J.iroiu, V.Towsley, J.Kurose. Modeling TCP Throughtput: A Simple Model and its Empirical Validation, Proc. ACM SIGCOMM 1998
[27] 傅清祥,王晓东.算法与数据结构[M],电子工业出版社,2001.8
[28] Al Bovik Handbook of Image&Video Processing[M], ACADEMIC PRESS, 1999
[29] http://www.libsdl.org/, 2006
[30] 陆其明,DirectShow实务精选[M],北京科海电子出版社,2004.7
[31] 李善平,陈文智,边干边学—Linux内核指导[M],浙江大学出版社,2002.8
[32] 毛德操,胡希明,Linux内核源代码情景分析上册[M],浙江大学出版社,2003.9
[33] 李善平,刘文峰,李程远,王焕龙,王伟波.Linux内核2.4版源代码分析大全[M],机械工业出版社,2002.1
[34] 龚建伟,熊光明.Turbo C串口通信编程实践[M],电子工业出版社,2004.10
[35] http://www.zoomtech.cn/chinese/download/down/Pelco_P.doc, 2004
[36] W.Richard Stevens著,施振川,周利民,孙宏晖等译,UNIX网络编程(第一卷)[M],清华大学出版社,1999.7
[37] Widmer, Jorg, Equation-Based Congestion Control, Diploma Thesis University of Mannheim, 2000.2.
[38] Ladan Gharai, Cloin Perkins. hnplementing Congestion Control in The Real World, Proc:IEEE, (USA), 2000, 6(1):Ⅵ-36-Ⅵ-39
[39] Li WP. MPEG-4 video standard, IEEE Yrans, On Circuits and Systems for Video Technology, 2001, 11(3):301-317
[40] Padhye J. Towards a comprehensive congestion control framework for Continuous media flows in best effort networks[D]. University of Massachusetts Amherst, 2005
[41] Widmer J. Equation based congestion control[D]. Dept of mathematics and Computer Science , University of Mannheim, 2000
[42] 黄奎,吴亦川,郑健平.TCP-Friendly Congestion Control Mechanism Based on Adaptive Weighted Average,软件学报,2005.16(12)
[43] 蒋心晓,牛红,牛荣健,张堃.RED HAT Linux7指令参考手册[M],人民邮电出版社,2001.10
[44] 谭浩强,C程序设计(第二版)[M],清华大学出版社,2000.4
[45] 许宏松,吴明行,廖世恩.Linux应用程序开发指南[M],机械工业出版社,2000.7
[46] Asit Dan, DinkarSitaram. Buffer Management Plocy for an On-Demand Video Server, IBM Research Division, RC 19347, Yorktown Heights, NY, 2004.