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Thomas Stockhammer - One of the best experts on this subject based on the ideXlab platform.

  • advancedwireless multiuser video streaming using the scalable video coding extensions of h 264 mpeg4 avc
    International Conference on Multimedia and Expo, 2006
    Co-Authors: Guenther Liebl, Thomas Schierl, Thomas Wiegand, Thomas Stockhammer
    Abstract:

    We propose a dynamic sharing of radio resources in a wireless multiuser system by combining a flexible video coding scheme, namely the currently developed scalable video coding (SVC) extension of H.264/AVC with appropriate radio Link Buffer management for multiuser streaming services. The paper introduces the components of the proposed system and the used cross-layer interface. Simulation results verify the benefits of our approach.

  • ICME - Advancedwireless Multiuser Video Streaming using the Scalable Video Coding Extensions of H.264/MPEG4-AVC
    2006 IEEE International Conference on Multimedia and Expo, 2006
    Co-Authors: Guenther Liebl, Thomas Schierl, Thomas Wiegand, Thomas Stockhammer
    Abstract:

    We propose a dynamic sharing of radio resources in a wireless multiuser system by combining a flexible video coding scheme, namely the currently developed scalable video coding (SVC) extension of H.264/AVC with appropriate radio Link Buffer management for multiuser streaming services. The paper introduces the components of the proposed system and the used cross-layer interface. Simulation results verify the benefits of our approach.

  • Radio Link Buffer Management and Scheduling for Wireless Video Streaming
    Telecommunication Systems, 2005
    Co-Authors: Günther Liebl, Hrvoje Jenkac, Thomas Stockhammer, Christian Buchner
    Abstract:

    In this paper we compare strategies for joint radio Link Buffer management and scheduling for wireless video streaming. Based on previous work in this area [8], we search for an optimal combination of scheduler and drop strategy for different end-to-end streaming options including timestamp-based streaming and ahead-of-time streaming, both with variable initial playout delay. We will show that a performance gain versus the two best drop strategies in Liebl et al. [8], i.e. drop the HOL packet or drop the packet with the lowest priority starting from HOL, is possible: Provided that some basic side-information on the structure of the incoming video stream is available, a more sophisticated drop strategy removes packets from an HOL group of packets in such a way that the temporal dependencies usually present in video streams are not violated. This advanced Buffer management scheme yields significant improvements for almost all investigated scheduling algorithms and streaming options. In addition, we will demonstrate the importance of fairness among users when selecting a suitable scheduler, especially if ahead-of-time streaming is to be applied: Given a reasonable initial playout delay at the streaming media client, both the overall achievable quality averaged over all users, as well as the individual quality of users with bad channel conditions can be increased significantly by trading off fairness with maximum throughput of the system.

  • ICN (1) - Joint Buffer management and scheduling for wireless video streaming
    Networking - ICN 2005, 2005
    Co-Authors: Günther Liebl, Hrvoje Jenkac, Thomas Stockhammer, Christian Buchner
    Abstract:

    In this paper we revisit strategies for joint radio Link Buffer management and scheduling for wireless video streaming. Based on previous work [1], we search for an optimal combination of scheduler and drop strategy for different end–to–end streaming options. We will show that a performance gain vs. the two best drop strategies in [1], ie drop the HOL packet or drop the lowest priority packet starting from HOL, is possible: Provided that basic side-information on the video stream structure is available, a more sophisticated strategy removes packets from an HOL group of packets such that the temporal dependencies usually present in video streams are not violated. This advanced Buffer management scheme yields significant improvements for almost all investigated scheduling algorithms and streaming options. In addition, we will demonstrate the importance of fairness among users when selecting a suitable scheduler.

Guenther Liebl - One of the best experts on this subject based on the ideXlab platform.

  • Proxy-based transmission strategies for wireless video streaming
    Packet Video 2007, 2007
    Co-Authors: Guenther Liebl, Eckehard Steinbach
    Abstract:

    We present proxy-based transmission strategies for improving the quality of delay-critical video streams which are transmitted in parallel on the downLink of a cellular system. Compared to state-of-the-art radio Link Buffer management, our solution allows to shape the rate of the incoming video streams in a rate-distortion optimized way before congestion may occur. Furthermore, joint optimization across multiple parallel streams is possible to avoid blocking of certain users by less important data units of others. The proposed solution only requires periodic reporting of abstract side information from the radio Link layer in terms of the current Buffer status and the average throughput. We demonstrate the improved perceptual quality and fairness that can be achieved with our solution for a simple downLink scenario.

  • advancedwireless multiuser video streaming using the scalable video coding extensions of h 264 mpeg4 avc
    International Conference on Multimedia and Expo, 2006
    Co-Authors: Guenther Liebl, Thomas Schierl, Thomas Wiegand, Thomas Stockhammer
    Abstract:

    We propose a dynamic sharing of radio resources in a wireless multiuser system by combining a flexible video coding scheme, namely the currently developed scalable video coding (SVC) extension of H.264/AVC with appropriate radio Link Buffer management for multiuser streaming services. The paper introduces the components of the proposed system and the used cross-layer interface. Simulation results verify the benefits of our approach.

  • ICME - Advancedwireless Multiuser Video Streaming using the Scalable Video Coding Extensions of H.264/MPEG4-AVC
    2006 IEEE International Conference on Multimedia and Expo, 2006
    Co-Authors: Guenther Liebl, Thomas Schierl, Thomas Wiegand, Thomas Stockhammer
    Abstract:

    We propose a dynamic sharing of radio resources in a wireless multiuser system by combining a flexible video coding scheme, namely the currently developed scalable video coding (SVC) extension of H.264/AVC with appropriate radio Link Buffer management for multiuser streaming services. The paper introduces the components of the proposed system and the used cross-layer interface. Simulation results verify the benefits of our approach.

Jack Y. B. Lee - One of the best experts on this subject based on the ideXlab platform.

  • On Queue Length and Link Buffer Size Estimation in 3G/4G Mobile Data Networks
    IEEE Transactions on Mobile Computing, 2014
    Co-Authors: Stanley C. F. Chan, K M Chan, Ke Liu, Jack Y. B. Lee
    Abstract:

    The emerging mobile data networks fueled by the world-wide deployment of 3G, HSPA, and LTE networks created new challenges for the development of Internet applications. Unlike their wired counterpart, mobile data networks are known to exhibit highly variable bandwidth. Moreover, base stations are often equipped with large Buffers to absorb bandwidth fluctuations to prevent unnecessary packet losses. Consequently to optimize protocol performance in mobile data networks it is essential to be able to accurately characterize two key network properties: queue length and Buffer size of the bottleneck Link. This work tackles the challenge in estimating these two network properties in modern mobile data networks. Using extensive trace-driven simulations based on actual bandwidth trace data measured from production mobile data networks, we show that existing queue-length and Link Buffer size estimation algorithms no longer work well in bandwidth-varying networks. We develop a novel sum-of-delays algorithm which incorporates the effect of bandwidth variations into its estimation. Extensive trace-driven simulation results show that it can accurately estimate the queue length and Link Buffer size under both fixed and varying bandwidth conditions, outperforming existing algorithms by up to two orders of magnitude.

  • WiMob - A novel Link Buffer size estimation algorithm for bandwidth-varying mobile data networks
    2011 IEEE 7th International Conference on Wireless and Mobile Computing Networking and Communications (WiMob), 2011
    Co-Authors: Stanley C. F. Chan, Jack Y. B. Lee
    Abstract:

    The rapidly emerging mobile data networks fueled by the world-wide deployment of 3G, HSPA, and LTE networks created new challenges for the development of Internet applications. Unlike their wired counterpart, mobile data networks are known to exhibit highly variable bandwidth. Moreover, base stations are often equipped with large Buffers to absorb bandwidth fluctuations to prevent unnecessary packet losses. However these two factors together invalidate the assumptions used in conventional protocol designs, which routers are assumed to have fixed Link capacity and a small Buffer. Consequently to optimize protocol performance in mobile data networks it is essential to be able to accurately characterize the network properties such as bottleneck Link Buffer size. This work tackles the challenge in estimating Link Buffer size in modern mobile data networks. Using extensive trace-driven simulations based on actual bandwidth trace data measured from production mobile data networks, we show that existing Link Buffer size estimation algorithms such as max-min and loss-pair no longer work well in bandwidth-varying networks. We develop a novel sum-of-delays algorithm to tackle this challenge. Simulation results show that it can accurately estimate the Link Buffer size under both fixed and varying bandwidth conditions, outperforming the existing algorithms by multiple orders of magnitude.

Thomas Schierl - One of the best experts on this subject based on the ideXlab platform.

Thomas Wiegand - One of the best experts on this subject based on the ideXlab platform.