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487
Mobile video transmission using scalable video coding
- IEEE Transactions on Circuits and Systems for Video Technology
, 2007
"... Abstract—The Scalable Video Coding (SVC) standard as an ex-tension of H.264/AVC allows efficient, standard-based temporal, spatial, and quality scalability of video bit streams. Scalability of a video bit stream allows for media bit rate as well as for device ca-pability adaptation. Moreover, adapta ..."
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Cited by 54 (2 self)
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Abstract—The Scalable Video Coding (SVC) standard as an ex-tension of H.264/AVC allows efficient, standard-based temporal, spatial, and quality scalability of video bit streams. Scalability of a video bit stream allows for media bit rate as well as for device ca-pability adaptation. Moreover, adaptation of the bit rate of a video signal is a desirable key feature, if limitation in network resources, mostly characterized by throughput variations, varying delay or transmission errors, need to be considered. Typically, in mobile networks the throughput, delay and errors of a connection (link) depend on the current reception conditions, which are largely in-fluenced by a number of physical factors. In order to cope with the typically varying characteristics of mobile communication chan-nels in unicast, multicast, or broadcast services, different methods for increasing robustness and achieving quality of service are desir-able. We will give an overview of SVC and its relation to mobile de-livery methods. Furthermore, innovative use cases are introduced which apply SVC in mobile networks. Index Terms—Content delivery, DVB-H, mobile, protocols, raptor codes, video, wireless, 3 GPP, H.264/AVC. I.
Traffic and Quality Characterization of Single-Layer Video Streams Encoded with the H.264/MPEG–4 Advanced Video Coding Standard and Scalable Video Coding Extension
"... The recently developed H.264/AVC video codec with Scalable Video Coding (SVC) extension, compresses non-scalable (single-layer) and scalable video significantly more efficiently than MPEG–4 Part 2. Since the traffic characteristics of encoded video have a significant impact on its network transport, ..."
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Cited by 45 (9 self)
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The recently developed H.264/AVC video codec with Scalable Video Coding (SVC) extension, compresses non-scalable (single-layer) and scalable video significantly more efficiently than MPEG–4 Part 2. Since the traffic characteristics of encoded video have a significant impact on its network transport, we examine the bit rate-distortion and bit rate variability-distortion performance of single-layer video traffic of the H.264/AVC codec and SVC extension using long CIF resolution videos. We also compare the traffic characteristics of the hierarchical B frames (SVC) versus classical B frames. In addition, we examine the impact of frame size smoothing on the video traffic to mitigate the effect of bit rate variabilities. We find that compared to MPEG–4 Part 2, the H.264/AVC codec and SVC extension achieve lower average bit rates at the expense of significantly increased traffic variabilities that remain at a high level even with smoothing. Through simulations we investigate the implications of this increase in rate variability on (i) frame losses when transmitting a single video, and (ii) on the number of supported video streams in a bufferless statistical multiplexing scenario with restricted link capacity and information loss. We find increased frame losses, and rate-distortion/rate-variability/encoding complexity tradeoffs. We conclude that solely assessing bit rate-distortion improvements of video encoder technologies is not sufficient to predict the performance in specific networked application scenarios. Index Terms Frame loss ratio, H.264/AVC, hierarchical B frames, rate-distortion (RD), rate variability-distortion (VD), single-layer video, statistical multiplexing, SVC, video traffic. I.
CloudStream: Delivering high-quality streaming videos through a cloud-based SVC proxy
- in Proc. IEEE INFOCOM Mini-conf
"... SVC proxy ..."
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Adaptive video streaming over a mobile network with TCP-friendly rate control
- in Proc. IWCMC, 2009
"... This paper investigates the performance of TCP-Friendly Rate Control (TFRC) to control the transmission rate of scalable video streams when used in a mobile network. The streams are encoded using the Scalable Video Coding (SVC) extension of the H.264/AVC standard. Adding or removing the layers is de ..."
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Cited by 19 (0 self)
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This paper investigates the performance of TCP-Friendly Rate Control (TFRC) to control the transmission rate of scalable video streams when used in a mobile network. The streams are encoded using the Scalable Video Coding (SVC) extension of the H.264/AVC standard. Adding or removing the layers is decided based on the TFRC during varying channel conditions of the mobile network. We conduct simulations in various realistic use cases, evaluate and compare the performance with and without TFRC-based adaptation. The results show significant improvements in terms of lower loss rate, delay, required buffer size and less playback interruption.
Video telephony for end-consumers: Measurement study of google+, ichat, and skype. http://eeweb.poly.edu/faculty/ yongliu/docs/imc12tech.pdf
, 2012
"... Video telephony requires high-bandwidth and low-delay voice and video transmissions between geographically distributed users. It is challenging to deliver high-quality video tele-phony to end-consumers through the best-effort Internet. In this paper, we present our measurement study on three popular ..."
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Cited by 16 (5 self)
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Video telephony requires high-bandwidth and low-delay voice and video transmissions between geographically distributed users. It is challenging to deliver high-quality video tele-phony to end-consumers through the best-effort Internet. In this paper, we present our measurement study on three popular video telephony systems on the Internet: Google+, iChat, and Skype. Through a series of carefully designed ac-tive and passive measurements, we are able to unveil impor-tant information about their key design choices and perfor-mance, including application architecture, video generation and adaptation schemes, loss recovery strategies, end-to-end voice and video delays, resilience against random and bursty losses, etc. Obtained insights can be used to guide the design of applications that call for high-bandwidth and low-delay data transmissions under a wide range of “best-effort ” net-work conditions.
Video transport evaluation with H.264 video traces
- Fourth Quarter
, 2012
"... Abstract—The performance evaluation of video transport mechanisms becomes increasingly important as encoded video accounts for growing portions of the network traffic. Compared to the widely studied MPEG-4 encoded video, the recently adopted H.264 video coding standards include novel mechanisms, suc ..."
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Cited by 16 (4 self)
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Abstract—The performance evaluation of video transport mechanisms becomes increasingly important as encoded video accounts for growing portions of the network traffic. Compared to the widely studied MPEG-4 encoded video, the recently adopted H.264 video coding standards include novel mechanisms, such as hierarchical B frame prediction structures and highly efficient quality scalable coding, that have important implications for network transport. This tutorial introduces a trace-based evaluation methodology for the network transport of H.264 encoded video. We first give an overview of H.264 video coding, and then present the trace structures for capturing the characteristics of H.264 encoded video. We give an overview of the typical video traffic and quality characteristics of H.264 encoded video. Finally, we explain how to account for the H.264 specific coding mechanisms, such as hierarchical B frames, in networking studies. Index Terms—H.264 encoded video, hierarchical B frames, medium grain scalability (MGS), network transport, simulation, traffic variability, video trace.
Chameleon: Adaptive Peer-toPeer Streaming with Network Coding
- Proc. of IEEE INFOCOM 2010
, 2009
"... Abstract—Layered streaming can be used to adapt to the available download capacity of an end-user, and such adaptation is very much required in real world HTTP media streaming. The multiple layer codec has become more refined, as SVC (the scalable extension of the H.264/AVC standard) has been standa ..."
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Cited by 15 (2 self)
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Abstract—Layered streaming can be used to adapt to the available download capacity of an end-user, and such adaptation is very much required in real world HTTP media streaming. The multiple layer codec has become more refined, as SVC (the scalable extension of the H.264/AVC standard) has been standardized with a bit rate overhead of around 10 % and an indistinguishable visual quality, compared to the state of the art single layer codec. Peer-to-peer streaming systems have also become the reality. The important question is how such layered coding can be used in real world peer-to-peer streaming systems. This paper tries to explore the feasibility of using network coding to make layered peer-to-peer streaming much more realistic, by combining network coding and SVC in a fine granularity manner. We present Chameleon, our new peer-to-peer streaming algorithm designed to incorporate network coding seamlessly with SVC. Key components with different design options of Chameleon are presented and experimentally evaluated, with the objective of investigating benefits of network coding in combination with SVC. We carry out extensive experiments on real stream data to (i) evaluate the performance of Chameleon in terms of playback skips and delivered video quality, and (ii) understand its insights. Our results demonstrate the feasibility of the approach and bring us one step closer to real adaptive peer-to-peer streaming. I.
1 Scalable Video Multicast in Hybrid 3G/Ad-hoc Networks
"... Mobile video broadcasting service, or mobile TV, is expected to become a popular application for 3G wireless network operators. Most existing solutions for video Broadcast Multicast Services (BCMCS) in 3G networks employ a single transmission rate to cover all viewers. The system-wide video quality ..."
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Cited by 15 (5 self)
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Mobile video broadcasting service, or mobile TV, is expected to become a popular application for 3G wireless network operators. Most existing solutions for video Broadcast Multicast Services (BCMCS) in 3G networks employ a single transmission rate to cover all viewers. The system-wide video quality of the cell is therefore throttled by a few viewers close to the boundary, and is far from reaching the social-optimum allowed by the radio resources available at the base station. In this paper, we propose a novel scalable video broadcast/multicast solution, SV-BCMCS, that efficiently integrates scalable video coding, 3G broadcast and ad-hoc forwarding to balance the system-wide and worst-case video quality of all viewers at 3G cell. In our solution, video is encoded into multiple layers. The base station broadcasts different layers at different rates to cover viewers at different ranges. All viewers are guaranteed to receive the base layer, and viewers closer to the base station can receive more enhancement layers. Using ad-hoc connections, viewers far away from the base station can obtain from their neighbors closer to the base station the enhancement layers that they cannot receive directly from the base station. We study the optimal resource allocation problem in SV-BCMCS and develop practical helper finding and relay routing algorithms. Through analysis and extensive OPNET simulations, we demonstrated that SV-BCMCS can significantly improve the system-wide video quality at the price of slight quality degradation of a few viewers close to the boundary.
Thread Tailor: Dynamically Weaving Threads Together for Efficient, Adaptive Parallel Applications
"... Extracting performance from modern parallel architectures requires that applications be divided into many different threads of execution. Unfortunately selecting the appropriate number of threads for an application is a daunting task. Having too many threads can quickly saturate shared resources, su ..."
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Cited by 15 (2 self)
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Extracting performance from modern parallel architectures requires that applications be divided into many different threads of execution. Unfortunately selecting the appropriate number of threads for an application is a daunting task. Having too many threads can quickly saturate shared resources, such as cache capacity or memory bandwidth, thus degrading performance. On the other hand, having too few threads makes inefficient use of the resources available. Beyond static resource assignment, the program inputs and dynamic system state (e.g., what other applications are executing in the system) can have a significant impact on the right number of threads to use for a particular application. To address this problem we present the Thread Tailor, a dynamic system that automatically adjusts the number of threads in an application to optimize system efficiency. The Thread Tailor leverages offline analysis to estimate what type of threads will exist at runtime and the communication patterns between them. Using this information Thread Tailor dynamically combines threads to better suit the needs of the target system. Thread Tailor adjusts not only to the architecture, but also other applications in the system, and this paper demonstrates that this type of adjustment can lead to significantly better use of thread-level parallelism in real-world architectures.
Optimal Bandwidth Sharing in Multi-Swarm Multi-Party P2P Video Conferencing Systems
"... In a multi-party video conference, multiple users simultaneously distribute video streams to their receivers. As the traditional server-based solutions incur high infrastructure and bandwidth cost, conventional Peer-to-Peer (P2P) solutions only leveraging end users’ upload bandwidth, are normally no ..."
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Cited by 14 (3 self)
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In a multi-party video conference, multiple users simultaneously distribute video streams to their receivers. As the traditional server-based solutions incur high infrastructure and bandwidth cost, conventional Peer-to-Peer (P2P) solutions only leveraging end users’ upload bandwidth, are normally not self-sustainable: the video streaming workload increases quadratically with the number of users as each user could generate and distribute video streams, while the user upload bandwidth only increases linearly. Recently, hybrid solutions have been proposed that employ helpers to address the bandwidth deficiency in P2P video conferencing swarms. It is also noticed that a system hosting multiple parallel conferencing swarms can benefit from cross-swarm bandwidth sharing. However, how to optimally share bandwidth in such systems has not been explored so far. In this paper, we study the optimal bandwidth sharing in multi-swarm multi-party P2P video conferencing systems with helpers and investigate two cross-swarm bandwidth sharing scenarios: 1) Swarms are independent and peers from different swarms share a common pool of helpers; 2) Swarms are cooperative and peers in a bandwidth-rich swarm can further share their bandwidth with peers in a bandwidth-poor swarm. For each scenario, we develop distributed algorithms for intra-swarm and inter-swarm bandwidth allocation under a utility-maximization framework. Through analysis and simulation, we show that the proposed algorithms are robust to peer dynamics, and can adaptively allocate peer and helper bandwidth across swarms so as to achieve the system-wide optimum.
