基于H.263协议的视频图像编码技术研究
|
摘要
今天，社会发展的步伐已迈进信息时代，随着超大规模集成电路的飞速发展，各种数字化技术特别是计算机软硬件及网络技术的日新月异，以数字通信为代表的各种先进的通信技术已进入普通家庭，多媒体通信业已成为现实，而国际互联网等各种信息网在全球的迅速扩展，使全世界真正成为一个“地球村“。然而，在以光纤通信为基础的信息高速公路开通以前，我们将面临一个重大的难题：一方面，需要传输的多媒体信息数据十分巨大；另一方面，现有的数字通信信道带宽有限。随着信息的多样化，复杂化及实时性要求的加强，巨大的数据量和狭窄的通信信道之间的矛盾日益突出。过去几年中，数字视频方面的应用引起了人们极大的兴趣，并出现了几种成功的标准，如：ITU-T H.261，H.263，ISO／IEC MPEG-1和MPEG-2。这些标准描述了依据比特率，图像质量，复杂度，抗误码和延迟等方面指标的广泛的应用范围。当前对数字视频应用的要求日益增加，比如：视频会议，视频邮件，视频电话，远程医疗等等。然而公众交换电话网(PSTN)和无线网络的传输码率仍然十分有限，这就需要优良的压缩性能和健壮的信道抗误码性，以前的基于块的视频编码标准(如H.261)是无法做到这一点的。“低码率通信视频编码标准“——ITU-T H.263，描述了上述要求，成为新一代低码率视频编码标准。尽管H.263的编码结构是基于H.261的，它却提供了低码率下更好的图像质量，而运算复杂度只有些微增加，并且增加了改进压缩性能的四个可选模式。在几种视频电话终端标准中，也采用了H.263，应用比较广泛的有：ITU-T H.324(PSTN)，H.320(ISDN)和H.310(B-ISDN)。所以，在现有的有限信道资源范围内，利用先进的编码技术进行数据压缩，实现视频信息传输，有着重要的经济和社会效益。这是当前研究的热点，也是本文的出发点。
本文的目标是实现一个高效率的具有良好抗误码性的视频图像编解码系统，该系统以H.263协议为基础，考虑到系统的编解码均用软件实现，因此系统设计的出发点是降低算法复杂度，提高编码效率同时改进抗误码性能。文中对视频处理的运动预测部分进行了改进，提高了预测的准确性并提高了错误恢
电子科技大学硕土学位论文
复能力。针对互联网的不稳定，易拥挤等特点，提出了一种新的传输策略，即
将一个图像帧用两个压缩腴进行传送，提高了错误恢复的可能性与可靠性。
In the past few years, there has been significant interest in digital video applications.Consequently,academic and industry have worked toward developing video compression techniques, and several successful standards have emerged,e.g.,ITU-T H.261,H.263,ISO/IEC MPEG-1 and MPEG-2.While the demand for digital video communication applications such as video conferencing,video e-mailing,telemedicine,and video telephony has increased considerably,transmission rates over public switched telephone networks (PSTN) and wireless networks are still very limited.This requires compression performance and channel error robustness levels. ITU-T H.263,entitled " Video Coding for Low Bit Rate Communications ", provides better picture quality at low bit rates with little additional complexity.lt also includes four optional modes aimed at improving compression performance,.In this thesis, the H.263 standard specially suitable for low bitrate transmission, is adopted for digital video compression.
The goal of this thesis is to develop a efficient video coding-decoding system having good error resilience. Specially,the concrete jobs of the thesis are:
Opitimizes motion estimation. The modified motion estimation algorithm use adjacent several frames as reference other than single frame.
Simplifies the algorithm of enhanced reference frame mode in H.263+ optinal mode.Therefore, multiframes reference adopt "sliding windows" method.
Proposes a new strategy of video transmission aiming at speciality of Internet,which is instable and easily congested.The strategy improves reliability of the error concealment method,and makes
breaking image get correctly recovered.
本文的目标是实现一个高效率的具有良好抗误码性的视频图像编解码系统，该系统以H.263协议为基础，考虑到系统的编解码均用软件实现，因此系统设计的出发点是降低算法复杂度，提高编码效率同时改进抗误码性能。文中对视频处理的运动预测部分进行了改进，提高了预测的准确性并提高了错误恢
电子科技大学硕土学位论文
复能力。针对互联网的不稳定，易拥挤等特点，提出了一种新的传输策略，即
将一个图像帧用两个压缩腴进行传送，提高了错误恢复的可能性与可靠性。
In the past few years, there has been significant interest in digital video applications.Consequently,academic and industry have worked toward developing video compression techniques, and several successful standards have emerged,e.g.,ITU-T H.261,H.263,ISO/IEC MPEG-1 and MPEG-2.While the demand for digital video communication applications such as video conferencing,video e-mailing,telemedicine,and video telephony has increased considerably,transmission rates over public switched telephone networks (PSTN) and wireless networks are still very limited.This requires compression performance and channel error robustness levels. ITU-T H.263,entitled " Video Coding for Low Bit Rate Communications ", provides better picture quality at low bit rates with little additional complexity.lt also includes four optional modes aimed at improving compression performance,.In this thesis, the H.263 standard specially suitable for low bitrate transmission, is adopted for digital video compression.
The goal of this thesis is to develop a efficient video coding-decoding system having good error resilience. Specially,the concrete jobs of the thesis are:
Opitimizes motion estimation. The modified motion estimation algorithm use adjacent several frames as reference other than single frame.
Simplifies the algorithm of enhanced reference frame mode in H.263+ optinal mode.Therefore, multiframes reference adopt "sliding windows" method.
Proposes a new strategy of video transmission aiming at speciality of Internet,which is instable and easily congested.The strategy improves reliability of the error concealment method,and makes
breaking image get correctly recovered.
引文
[1] 余松煜等编，《数字图像处理》，电子工业出版社，1989年．
[2] 吴成柯等编，《图像通信》，西安电子科技大学，1992年．
[3] 《C语言数值算法程序大全(第二版)》，电子工业出版社，1995年．
[4] 王国印译，《Visual C++技术内幕(第二版)》，清华大学出版社，1995年．
[5] 黎洪松编，《数字视频技术及其应用》，清华大学出版社，1997年．
[6] 刘东华等，“远程医疗信息系统及其应用中的问题“，医疗装备，1999．
[7] 朱秀昌等编，《会议电视系统及应用技术》，人民邮电出版社，1999．
[8] 聂秀英等译，《多媒体通信网络——技术与业务》，人民邮电出版社，2001．
[9] 王道义等译，《TCL／TK组合教程》，电子工业出版社，2001．
[10] 江春等译，《数字视频处理》，电子工业出版社，1998．
[11] ITU Telecom. Standardization Sector of ITU, "Video Coding for Low Bit Rate Communication," Draft ITU-T Recommendation H.263, March 1996.
[12] ITU Telecom. Standardization Sector of ITU, "Video Coding for Low Bit Rate Communication," Draft ITU-T Recommendation H.263 Version2, September 1997.
[13] Eckehard Steinbach, Niko Farber, and Bernd Girod, "Standard Compatible Extension of H.263 for Robust Video Transmission in Mobile Environments",IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, VOL.7,NO.6, DECEMBER 1997.
[14] Frank H.P. Span, Reginald L.Lagendijk, Jun Biemond, "Error Robust Video Coding Based on H.263", International Conference Image Processing, 1998.
[15] Han-Seung Jung, Rin-Chul Kim, Sang-Uk Lee, "On the Robust Transmission Technique for H.263 Video Data Stream Over Wirless Networks", International Conference Image Processing, 1998.
[16] The Test Model Near-Term(TMN11) for the ITU-T Recommendation H.263,Version2. ITU-Telecommunication Standardiation Sector STUDY GROUP16, Video Coding Experts Group, February, 1999.
[17] Wee Sun Lee, Mark R. Pickering, Michael R. Frater, and John F. Arnold, "Error
Resilience in Video and Multiplexing Layers for Very Low Bit-Rate Video Coding Systems", IEEE Journal On Selected Areas In Communication, 1997．
[18] Hang Liu and Magda EI Zarki, "Performance of H.263 Video Transmission over Wireless Channels Using Hybrid ARQ", IEEE Journal On Selected Areas In Communication, 1997．
[19] ITU Telecom. Standardization Sector of ITU, "DRAFT FOR 'H.263++' ANNEXES U,V,AND W TO RECOMMENDATION H.263," ITU-T Recommendation H.263++, November 2000．
[20] Demonstration of H.263++ Annex U Performance, Polycom.
[21] ITU Telecom. Standardization Sector of ITU, "Video Coding for Low Bit Rate Communication," ITU-T Recommendation H.263 Version2, February 1998
[22] ITU Telecom. Standardization Sector of ITU, "H.263+, Video Coding at Low Bit Rates," IEEE TRANSANCTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, VOL.8, NO.7． , November 1998
[23] Paul Salama, "ERROR CONCEALMENT IN ENCODED IMAGES AND VIDEO", August 1999
[24] ITU Telecom. Standardization Sector of ITU, "DRAFT FOR 'H.263++' ANNEXES U,V,AND W TO RECOMMENDATION H.263," ITU-T Recommendation H.263++, November 2000．
[25] Yao Wang, Stephan Wenger, Jiangtao Wen, and Aggelos K.Katsaggelos, "Review of Error Resilient Coding Techniques for Real-Time Video Commmunications", 1998．
[26] Alexander E. Mohr, "An Algorithm for Protecting Medical Images that are Transmitted over Channels with Packet Loss", March 1999．
[2] 吴成柯等编，《图像通信》，西安电子科技大学，1992年．
[3] 《C语言数值算法程序大全(第二版)》，电子工业出版社，1995年．
[4] 王国印译，《Visual C++技术内幕(第二版)》，清华大学出版社，1995年．
[5] 黎洪松编，《数字视频技术及其应用》，清华大学出版社，1997年．
[6] 刘东华等，“远程医疗信息系统及其应用中的问题“，医疗装备，1999．
[7] 朱秀昌等编，《会议电视系统及应用技术》，人民邮电出版社，1999．
[8] 聂秀英等译，《多媒体通信网络——技术与业务》，人民邮电出版社，2001．
[9] 王道义等译，《TCL／TK组合教程》，电子工业出版社，2001．
[10] 江春等译，《数字视频处理》，电子工业出版社，1998．
[11] ITU Telecom. Standardization Sector of ITU, "Video Coding for Low Bit Rate Communication," Draft ITU-T Recommendation H.263, March 1996.
[12] ITU Telecom. Standardization Sector of ITU, "Video Coding for Low Bit Rate Communication," Draft ITU-T Recommendation H.263 Version2, September 1997.
[13] Eckehard Steinbach, Niko Farber, and Bernd Girod, "Standard Compatible Extension of H.263 for Robust Video Transmission in Mobile Environments",IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, VOL.7,NO.6, DECEMBER 1997.
[14] Frank H.P. Span, Reginald L.Lagendijk, Jun Biemond, "Error Robust Video Coding Based on H.263", International Conference Image Processing, 1998.
[15] Han-Seung Jung, Rin-Chul Kim, Sang-Uk Lee, "On the Robust Transmission Technique for H.263 Video Data Stream Over Wirless Networks", International Conference Image Processing, 1998.
[16] The Test Model Near-Term(TMN11) for the ITU-T Recommendation H.263,Version2. ITU-Telecommunication Standardiation Sector STUDY GROUP16, Video Coding Experts Group, February, 1999.
[17] Wee Sun Lee, Mark R. Pickering, Michael R. Frater, and John F. Arnold, "Error
Resilience in Video and Multiplexing Layers for Very Low Bit-Rate Video Coding Systems", IEEE Journal On Selected Areas In Communication, 1997．
[18] Hang Liu and Magda EI Zarki, "Performance of H.263 Video Transmission over Wireless Channels Using Hybrid ARQ", IEEE Journal On Selected Areas In Communication, 1997．
[19] ITU Telecom. Standardization Sector of ITU, "DRAFT FOR 'H.263++' ANNEXES U,V,AND W TO RECOMMENDATION H.263," ITU-T Recommendation H.263++, November 2000．
[20] Demonstration of H.263++ Annex U Performance, Polycom.
[21] ITU Telecom. Standardization Sector of ITU, "Video Coding for Low Bit Rate Communication," ITU-T Recommendation H.263 Version2, February 1998
[22] ITU Telecom. Standardization Sector of ITU, "H.263+, Video Coding at Low Bit Rates," IEEE TRANSANCTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, VOL.8, NO.7． , November 1998
[23] Paul Salama, "ERROR CONCEALMENT IN ENCODED IMAGES AND VIDEO", August 1999
[24] ITU Telecom. Standardization Sector of ITU, "DRAFT FOR 'H.263++' ANNEXES U,V,AND W TO RECOMMENDATION H.263," ITU-T Recommendation H.263++, November 2000．
[25] Yao Wang, Stephan Wenger, Jiangtao Wen, and Aggelos K.Katsaggelos, "Review of Error Resilient Coding Techniques for Real-Time Video Commmunications", 1998．
[26] Alexander E. Mohr, "An Algorithm for Protecting Medical Images that are Transmitted over Channels with Packet Loss", March 1999．