Network-adaptive HD MPEG-2 video streaming with cross-layered channel monitoring in WLAN  

作　　者：PARK Sanghoon YOON Hayoung KIM Jongwon 

机构地区：[1]Networked Media Laboratory, Department of Information and Communications, GwangJu Institute of Science and Technology, Gwangju 500-712, Korea

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2006年第5期885-893,共9页浙江大学学报（英文版）A辑（应用物理与工程）

基　　金：Project (No. R05-2004-000-10987-0) partly supported by the Basic Research Program of the Korea Research Foundation

摘　　要：In this paper, we propose a practical design and implementation of network-adaptive high definition (HD) MPEG-2 video streaming combined with cross-layered channel monitoring (CLM) over the IEEE 802.11a wireless local area network (WLAN). For wireless channel monitoring, we adopt a cross-layered approach, where an access point (AP) periodically measures lower layers such as medium access control (MAC) and physical (PHY) transmission information (e.g., MAC layer loss rate) and then sends the monitored information to the streaming server application. The adaptive streaming server with the CLM scheme reacts more quickly and efficiently to the fluctuating wireless channel than the end-to-end application-layer monitoring (E2EM) scheme. The streaming server dynamically performs priority-based frame dropping to adjust the sending rate according to the measured wireless channel condition. For this purpose, the proposed streaming system nicely provides frame-based prioritized packetization by using a real-time stream parsing module. Various evaluation results over an IEEE 802.11a WLAN testbed are provided to verify the intended Quality of Service (QoS) adaptation capability. Experimental results showed that the proposed system can mitigate the quality degradation of video streaming due to the fluctuations of time-varying channel.In this paper, we propose a practical design; implementation of network-adaptive high definition (HD) MPEG-2 video streaming combined with cross-layered channel monitoring (CLM) over the IEEE 802.11a wireless local area network (WLAN). For wireless channel monitoring, we adopt a cross-layered approach, where an access point (AP) periodically measures lower layers such as medium access control (MAC); physical (PHY) transmission information (e.g., MAC layer loss rate); then sends the monitored information to the streaming server application. The adaptive streaming server with the CLM scheme reacts more quickly; efficiently to the fluctuating wireless channel than the end-to-end application-layer monitoring (E2EM) scheme. The streaming server dynamically performs priority-based frame dropping to adjust the sending rate according to the measured wireless channel condition. For this purpose, the proposed streaming system nicely provides frame-based prioritized packetization by using a real-time stream parsing module. Various evaluation results over an IEEE 802.11a WLAN testbed are provided to verify the intended Quality of Service (QoS) adaptation capability. Experimental results showed that the proposed system can mitigate the quality degradation of video streaming due to the fluctuations of time-varying channel.

关 键 词：Wireless video  ADAPTIVE VIDEO streaming  Cross-layered design  Prioritized packetization  MPEG-2 

分 类 号：TN919.8[电子电信—通信与信息系统]