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46
Model-based Distortion Estimation For Perceptual Classification of Video Packets
- in Proc. of IEEE Workshop on Multimedia Signal Processing (MMSP
, 2004
"... Abstract — In video communications over IP networks, quality of service (QoS) guarantees must be introduced to limit the effect of packet losses. In particular, end–to–end QoS can be improved if packets are protected according to the distortion that would be introduced at the receiver by their loss. ..."
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Cited by 12 (3 self)
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Abstract — In video communications over IP networks, quality of service (QoS) guarantees must be introduced to limit the effect of packet losses. In particular, end–to–end QoS can be improved if packets are protected according to the distortion that would be introduced at the receiver by their loss. In the traditional Analysis–by–Synthesis (AbS) approach, each packet is assumed lost, error concealment applied, the sequence decoded and the resulting overall distortion computed. This process produces reliable distortion estimates, but is computationally demanding. In this work we present a hybrid approach: the distortion introduced in the current frame is evaluated with the AbS method, while the distortion in future frames is estimated by means of a statistical error–propagation model. Results obtained on eight, widely different H.264 sequences show that the proposed model successfully estimates overall distortion with very low complexity. Network simulations also show that model–based packet classification, when used for video transmission over DiffServ networks, delivers PSNR results which are consistently within 0.1 dB compared to the AbS technique. I.
Quantitative Assessment of User-Level QoS and its Mapping
"... Abstract — This paper proposes a scheme for quantitative assessment of user-level (or perceptual) QoS for audio-video transmission by means of two psychometric methods: the method of paired comparisons and the law of comparative judgment. Moreover, we discuss QoS mapping from application-level QoS t ..."
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Cited by 11 (6 self)
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Abstract — This paper proposes a scheme for quantitative assessment of user-level (or perceptual) QoS for audio-video transmission by means of two psychometric methods: the method of paired comparisons and the law of comparative judgment. Moreover, we discuss QoS mapping from application-level QoS to user-level QoS by principal component analysis and multiple regression analysis. In the assessment, we simulate the transmission of an audio-video stream over a loaded network. In order to investigate the effect of the contents on QoS mapping, we treat two types of audio-video streams. By experiment, we demonstrate that our scheme can construct an interval scale as the user-level QoS parameter for each stream and represent it as a function of two application-level QoS parameters with high accuracy. We notice that the multiple regression line depends on the contents. We also propose the concept of control gain by media synchronization, which indicates how much media synchronization control subjectively lightens the average network load. Index Terms — user-level QoS, psychometric methods, QoS mapping, multiple regression analysis, principal component analysis. I.
Advances in Network-adaptive Video Streaming
- in Proc. of the International Workshop on Digital Communications (IWDC 2002
, 2002
"... Internet transmission is characterized by variations in throughput, delay, and packet loss, which can severely affect the quality of multimedia presentations delivered over the network. Still, Internet video streaming has experienced phenomenal growth in the last few years, owing to the extensive re ..."
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Cited by 9 (1 self)
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Internet transmission is characterized by variations in throughput, delay, and packet loss, which can severely affect the quality of multimedia presentations delivered over the network. Still, Internet video streaming has experienced phenomenal growth in the last few years, owing to the extensive research in video coding and transmission. In this paper, we review several recent advances for network-adaptive video streaming that, we believe, will benefit the design of video streaming systems in the future. Employed in different system components, these techniques have the common objective of providing efficient, robust, scalable and low-latency streaming video. They range from purely server or source encoder-based techniques, through transmission schemes that could be implemented either at the sender or at the receiver, to purely client-based techniques. We discuss each of them in detail, presenting also related work and experimental results. We end the paper with a summary of the reviewed techniques and a brief discussion of future research directions.
An automated policy-based management framework for differentiated communication systems
- IEEE Journal on Selected Areas in Communications
, 2005
"... Abstract—This paper presents a novel paradigm to approach the issue of autonomous policy-based management of wired/wireless differentiated communication systems. In contrast to existing management approaches which require static a priori policy configurations, policies are created dynamically. The p ..."
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Cited by 9 (0 self)
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Abstract—This paper presents a novel paradigm to approach the issue of autonomous policy-based management of wired/wireless differentiated communication systems. In contrast to existing management approaches which require static a priori policy configurations, policies are created dynamically. The proposed framework addresses the management issue from a new perspective through posing it as a problem of learning from current system behavior, while creating new policies at runtime in response to changing requirements. A hierarchical policy model is used to capture users and administrators ’ higher level goals into network level objectives. Given sets of network objectives and constraints, policies are assembled at runtime. The new approach gives more flexibility to users and applications to dynamically change their quality-of-service (QoS) requirements while maintaining a smooth delivery of QoS through network monitors feedback. Simulation results demonstrate the performance of the proposed work. Index Terms—Adaptive policies, autonomic communication systems, policy-based management, quality-of-service (QoS). I.
Optimized Cross-Layer Design for Scalable Video Transmission over the IEEE 802.11e Networks
"... Abstract — A cross-layer design for optimizing 3D wavelet scalable video transmission over the IEEE 802.11e networks is proposed. A thorough study on the behavior of the IEEE 802.11e protocol is conducted. Based on our findings, all timescales rate control is developed featuring a unique property of ..."
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Cited by 8 (0 self)
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Abstract — A cross-layer design for optimizing 3D wavelet scalable video transmission over the IEEE 802.11e networks is proposed. A thorough study on the behavior of the IEEE 802.11e protocol is conducted. Based on our findings, all timescales rate control is developed featuring a unique property of soft capacity support for multimedia delivery. The design consists of a macro timescale and a micro timescale rate control schemes residing at the application layer and the network sublayer respectively. The macro rate control uses bandwidth estimation to achieve optimal bit allocation with minimum distortion. The micro rate control employs an adaptive mapping of packets from video classifications to appropriate network priorities which preemptively drops less important video packets to maximize the transmission protection to the important video packets. The performance is investigated by simulations highlighting advantages of our crosslayer design.
Multi-layer Active Queue Management and Congestion Control for Scalable Video Streaming
- IN PROC. IEEE ICDCS
, 2004
"... Video streaming is becoming an increasingly important part of the current Internet; however, before high-quality streaming becomes a reality, the best-effort model of the Internet may need to be adapted to provide certain scalable services specifically targeted at video flows. In this paper, we stud ..."
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Cited by 7 (4 self)
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Video streaming is becoming an increasingly important part of the current Internet; however, before high-quality streaming becomes a reality, the best-effort model of the Internet may need to be adapted to provide certain scalable services specifically targeted at video flows. In this paper, we study one such mechanism and propose a new video streaming framework, which allows applications to mark their own packets with different priority and use multi-queue congestion control inside routers to automatically drop the less-important packets during buffer overflows. We describe priority AQM algorithms that provide optimal performance for video applications and study a variation of Kelly's congestion controls as part of this framework. Through simulation and analytical investigation, we find that our AQM based solution allows the application to maintain a much higher quality of video for the end-user compared to similar scenarios in a best-effort network. We call the combined framework PELS --- Partitioned Enhancement Layer Streaming.
A Simulative Study of Analysis-By-Synthesis Perceptual Video Classification and Transmission over DiffServ IP Networks,”
- IEEE International Conference on Communications (ICC),
, 2003
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Adaptive packet classification for constant perceptual quality of service delivery of video streams over time-varying networks
- in Proc. ICME
, 2003
"... This paper describes a technique to deliver video streams with constant perceptual quality of service (QoS) over time-varying packeterasure channels that support differentiated classes of service. During compression, the encoder estimates the distortion introduced at the decoder by each video packet ..."
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Cited by 5 (0 self)
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This paper describes a technique to deliver video streams with constant perceptual quality of service (QoS) over time-varying packeterasure channels that support differentiated classes of service. During compression, the encoder estimates the distortion introduced at the decoder by each video packet both in case it is received and in case it is lost. Concealment and error propagation due to inter-frame prediction are taken into account. During transmission, an optimization algorithm assigns packets to different service classes according to the estimated distortion, the current channel status and a constraint on the desired quality at the receiver. This technique is compared with other video packet classification approaches in the specific case of a DiffServ IP network implementing the Assured Forwarding scheme. Network simulations show that the proposed technique delivers higher and more constant levels of perceptual QoS than traditional approaches. Moreover, the technique is characterized by reactiveness to congestions and fairness in the use of network resources. 1.
Offset distortion traces for trace-based evaluation of video quality after network transport (extended version),” Apr. 2005, availabe from http://trace.eas.asu.edu
"... Abstract — Video traces containing the sizes and (PSNR) quali-ties of the individual frames of a video encoding are a convenient video representation for the evaluation of video networking mechanisms. These video traces can be used to find the frame loss probabilities of a lossy networking mechanism ..."
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Cited by 4 (3 self)
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Abstract — Video traces containing the sizes and (PSNR) quali-ties of the individual frames of a video encoding are a convenient video representation for the evaluation of video networking mechanisms. These video traces can be used to find the frame loss probabilities of a lossy networking mechanism, but can not give the PSNR video quality after lossy network transport. To date the video quality after lossy network transport could only be determined through experiments with actual video or by approximating the quality of the frames affected by a loss with some low PSNR quality. In this paper we introduce and evaluate offset distortion traces with which the video quality after lossy network transport can be accurately determined without requiring experiments with actual video. We explain how the offset distortion traces can be used by networking researchers without equipment or experience in video signal processing to accurately evaluate video networking mechanisms in terms of the PSNR video quality. Index Terms — Offset distortion, video traces, video quality estimation, PSNR, RMSE I.
