臺灣博碩士論文加值系統

可調視訊編碼(SVC)是一種可以針對播放設備以及網路頻寬，彈性的調整傳送出去位元流的影像壓縮技術，微波存取全球互通(WIMAX)是無線通訊上的新技術，我們的研究目的在於結合可調視訊編碼與微波存取全球互通的特性，在即時視訊傳送端提出一個系統上跨層的設計方法，以減少頻寬變動與無線通道品質的干擾，讓可調視訊編碼的播放端可以流暢的播放視訊影像。
在本論文中，我們提出一個跨層的設計架構以及提出一個頻寬回報機制，這個頻寬回報機制將會根據最新的頻寬訊息，決定出一個最適合未來一段時間的估計頻寬，回報給可調視訊編碼應用層，進而調整所要傳送的位元流。利用我們所提出的跨層架構以及頻寬回報機制來傳送即時視訊影像,將會在播放延遲、頻寬使用率以及資料緩衝區所累積的資料大小有著不錯的表現.

Scalable video coding (SVC) is a video compression technique which provides flexible bitstream extraction according to device types and network bandwidth, and WIMAX is a new wireless communication technique. Combining the two techniques to transmit multimedia information is an important application in the future. Our research goal is to reduce the impact of the variation of network bandwidth and channel condition on real time video communication based on above newly developed techniques.
In our thesis, we propose a cross-layer architecture between SVC system and WIMAX MAC, and we also propose a mechanism to decide the bitrate of the extracted SVC bitstream. According to the latest bandwidth information, this mechanism could decide a proper bitrate to fit the bandwidth of a period in the future, and then feedback this bitrate to SVC extractor. Thus SVC extractor can extract the proper size of SVC bitstream to transmit. Finally, with the proposed architecture and mechanism, we can achieve good performance in video latency, bandwidth utilization, and buffer condition during the real time video transportation.

摘 要 i
ABSTRACT ii
誌 謝 iii
Contents iv
Figures vi
Chapter 1 Research Overview 1
1.1 Problem Statement 1
1.2 Research Approach 2
1.3 Thesis Outline 2
Chapter 2 Overview of 802.16e System 3
2.1 Introduction to PHY Layer of 802.16e PHY 3
2.1.1 OFDMA PHY Frame Structure 4
2.1.2 PHY Slot And Data Mapping 5
2.1.3 Subcarrier Permutation 7
2.1.4 Adaptive Modulation And Coding (AMC) 8
2.2 Introduction to MAC Layer of 802.16e MAC 9
2.2.1 Layer Structure 9
2.2.2 MAC PDU Formats 10
2.2.3 Fragmentation And Packing 11
2.2.4 QoS Based Service Classes 12
Chapter 3 Overview of Scalable Video Coding 14
3.1 Introduction to Scalable Video Coding 14
3.2 Encoder Overview 14
3.3 Hierarchical-B Prediction Structure 15
3.4 Inter-layer Prediction Structure 16
Chapter 4 The Proposed Cross-Layer Design 18
4.1 The Design Issues 18
4.2 The Proposed Cross-Layer Architecture 19
4.3 The Bitrate Decision Engine 20
4.4 Discussion: The reason why enhanced feedback control mechanism can improve the performance of latency issue 23
Chapter 5 Simulation Setup and Results 24
5.1 Simulation Setup 24
5.1.1 Cell Plane 24
5.1.2 BS Antenna Pattern For 3-sector Cells 25
5.1.3 Path Loss Model 26
5.1.4 Shadowing Model 27
5.1.5 Available Slots of UL-MAP Simulation 27
5.1.6 System Parameters Setting 28
5.2 Simulation Results 29
5.2.1 Performance of conventional feedback control mechanism 29
5.2.2 Performance of enhanced feedback control mechanism 32
Chapter 6 Conclusion 41
6.1 Conclusion 41
6.2 Future Work 41

[1] Peng Chen, Jeongyeon Lim, Bumshik Lee and Munchurl Kim, “A network-adaptive SVC Streaming Architecture,” the 9th international conference on advanced communication technology, pp: 955-960, Feb.2007.
[2] Haechul Choi, Jung Won Kang and Jae-Gon Kim, "Dynamic and Interoperable Adaptation of SVC for QoS-Enabled Streaming," Consumer Electronics, IEEE Transactions on, vol. 53, pp. 384-389, 2007.
[3] IEEE 802.16.IEEE Standard for Local and Metropolitan Area Networks-Part 16.Air Interface for Fixed Broadband Wireless Access Systems-2005.
[4] IEEE 802.16.IEEE Standard for Local and Metropolitan Area Networks-Part 16.Air Interface for Fixed Broadband Wireless Access Systems-2004
[5] J.REICHEL, H.SCHWARZ, AND M. WIEN, “JOINT DRAFT 7 OF SVC AMENDMENT,” JOINT VIDEO TEAM (JVT) OF ISO/IEC MPEG & ITU-T VCEQ, JVT-T201, JULY 2006.
[6] “ISO/IEC ITU-T RECOMMENDATION H264 : ADVANCED VIDEO CODING FOR GENERIC AUDIOVISUAL SERVICES,” JOINT VIDEO TEAM (JVT) OF ISO/IEC MPEG & ITU-T VCEG,” INTERNATIONAL STANDARD, MAY 2003.
[7] Hsiang-Chun Huang, Wen-Hsiao Peng, Tihao Chiang and Hsueh-Ming Hang, "Advances in the scalable amendment of H.264/AVC," Communications Magazine, IEEE, vol. 45, pp. 68-76, 2007.
[8] “IEEE 802.16m Evaluation Methodology,” IEEE Standard Draft Document.