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162
An Evaluation Framework for More Realistic Simulations of MPEG Video Transmission
- Journal of
"... We present a novel and complete tool-set for evaluating the delivery quality of MPEG video transmissions in simulations of a network environment. This tool-set is based on the EvalVid framework. We extend the connecting interfaces of EvalVid to re-place its simple error simulation model by a more ge ..."
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We present a novel and complete tool-set for evaluating the delivery quality of MPEG video transmissions in simulations of a network environment. This tool-set is based on the EvalVid framework. We extend the connecting interfaces of EvalVid to re-place its simple error simulation model by a more general network simulator like NS2. With this combination, researchers and practitioners in general can analyze through simulation the performance of real video streams, i.e. taking into account the video se-mantics, under a large range of network scenarios. To demonstrate the usefulness of our new tool-set, we point out that it enables the investigation of the relationship between two popular objective metrics for Quality of Service (QoS) assessment of video quality delivery: the PSNR (Peak Signal to Noise Ratio) and the fraction of decodable frames. The results show that the fraction of decodable frames reflects well the behavior of the PSNR metric, while being less time-consuming. Therefore, the fraction of decodable frames can be an alternative metric to objectively assess through simulations the delivery quality of transmission in a network of publicly available video trace files.
Efficient error estimating coding: Feasibility and applications
- In Proc. ACM SIGCOMM
, 2010
"... Motivated by recent emerging systems that can leverage partially correct packets in wireless networks, this paper proposes the novel concept of error estimating coding (EEC). Without correcting the errors in the packet, EEC enables the receiver of the packet to estimate the packet’s bit error rate, ..."
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Cited by 19 (1 self)
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Motivated by recent emerging systems that can leverage partially correct packets in wireless networks, this paper proposes the novel concept of error estimating coding (EEC). Without correcting the errors in the packet, EEC enables the receiver of the packet to estimate the packet’s bit error rate, which is perhaps the most important meta-information of a partially correct packet. Our EEC design provides provable estimation quality, with rather low redundancy and computational overhead. To demonstrate the utility of EEC, we exploit and implement EEC in two wireless network applications, Wi-Fi rate adaptation and real-time video streaming. Our real-world experiments show that these applications can significantly benefit from EEC. 1
Video transport evaluation with H.264 video traces
, 2011
"... 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 hie ..."
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Cited by 18 (4 self)
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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.
Inferring the QoE of HTTP Video Streaming from User-Viewing Activities
- In SIGCOMM W-MUST
, 2011
"... HTTP video streaming, employed by most of the videosharing websites, allows users to control the video playback using, for example, pausing and switching the bit rate. These user-viewing activities can be used to mitigate the temporal structure impairments of the video quality. On the other hand, ot ..."
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Cited by 11 (0 self)
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HTTP video streaming, employed by most of the videosharing websites, allows users to control the video playback using, for example, pausing and switching the bit rate. These user-viewing activities can be used to mitigate the temporal structure impairments of the video quality. On the other hand, other activities, such as mouse movement, do not help reduce the impairment level. In this paper, we have performed subjective experiments to analyze userviewing activities and correlate themwith networkpathperformance and user quality of experience. The results show that network measurement alone may miss important information about user dissatisfaction with the video quality. Moreover, video impairments can trigger user-viewing activities, notably pausing and reducing the screen size. By including the pause events into the prediction model, we can increase its explanatory power.
A “GAP-Model ” based Framework for Online VVoIP QoE
"... Abstract: Increased access to broadband networks has led to a fast-growing demand for Voice and Video over IP (VVoIP) applications such as Internet telephony (VoIP), videoconferencing, and IP television (IPTV). For pro-active troubleshooting of VVoIP performance bottlenecks that manifest to end-user ..."
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Cited by 9 (0 self)
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Abstract: Increased access to broadband networks has led to a fast-growing demand for Voice and Video over IP (VVoIP) applications such as Internet telephony (VoIP), videoconferencing, and IP television (IPTV). For pro-active troubleshooting of VVoIP performance bottlenecks that manifest to end-users as performance impairments such as video frame freezing and voice dropouts, network operators cannot rely on actual end-users to report their subjective Quality of Experience (QoE). Hence, automated and objective techniques that provide real-time or online VVoIP QoE estimates are vital. Objective techniques developed to-date estimate VVoIP QoE by performing frame-to-frame Peak-Signal-to-Noise Ratio (PSNR) comparisons of the original video sequence and the reconstructed video sequence obtained from the sender-side and receiver-side, respectively. Since processing such video sequences is time consuming and computationally intensive, existing objective techniques cannot provide online VVoIP QoE. In this paper, we present a novel framework that can provide online estimates of VVoIP QoE on network paths without end-user involvement and without requiring any video sequences. The framework features the “GAP-Model”, which is an offline model of QoE expressed as a function of measurable network factors such as bandwidth, delay, jitter, and loss. Using the GAP-model, our online framework can produce VVoIP QoE estimates in terms of “Good”, “Acceptable” or “Poor ” (GAP) grades of perceptual quality solely from the online measured network conditions. Index Terms: Network management, user QoE, video quality. I.
A Distortion-minimizing Rate Controller for Wireless Multimedia Sensor Networks
- Computer Communications (Elsevier
, 2010
"... Abstract—The availability of inexpensive CMOS cameras and microphones that can ubiquitously capture multimedia content from the environment is fostering the development of Wireless Multimedia Sensor Networks (WMSNs), i.e., distributed systems of wirelessly networked devices that can retrieve video a ..."
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Cited by 9 (6 self)
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Abstract—The availability of inexpensive CMOS cameras and microphones that can ubiquitously capture multimedia content from the environment is fostering the development of Wireless Multimedia Sensor Networks (WMSNs), i.e., distributed systems of wirelessly networked devices that can retrieve video and audio streams, still images, and scalar sensor data. WMSNs require the sensor network paradigm to be re-thought in view of the need for mechanisms to deliver multimedia content with a pre-defined level of quality of service (QoS). A new rate control scheme for WMSNs is introduced in this paper with a two-fold objective: i) maximize the video quality of each individual video stream; ii) maintain fairness in video quality between different video streams. The rate control scheme is based on both analytical and empirical models and consists of a new cross-layer control algorithm that jointly regulates the end-to-end data rate, the video quality, and the strength of the channel coding at the physical layer. The end-to-end data rate is regulated to avoid congestion while maintaining fairness in the domain of video quality rather than data rate. Once the endto-end data rate has been determined, the sender adjusts the video encoder rate and the channel encoder rate based on the overall rate and the current channel quality, with the objective of minimizing the distortion of the received video. Simulations show that the proposed algorithm considerably improves the received video quality without sacrificing fairness. I.
performance evaluation
"... IEEE 802.16e is a mobile version of Worldwide Interoperability for Microwave Access (WiMAX) that plays an important role in the evolution towards 4G. In this study, we focus on multimedia performance measurement for the purpose of a more realistic mobile WiMAX network test. This study aims to make a ..."
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Cited by 7 (3 self)
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IEEE 802.16e is a mobile version of Worldwide Interoperability for Microwave Access (WiMAX) that plays an important role in the evolution towards 4G. In this study, we focus on multimedia performance measurement for the purpose of a more realistic mobile WiMAX network test. This study aims to make a contribution in better understanding the mobile WiMAX performance for multimedia applications. For that purpose, we employ Voice over Internet Protocol (VoIP) and video streaming to test the network performance, where two distinct evaluation systems are used, professional and user-friendly. Our test results show that the mobile WiMAX network can support well the bandwidth-intense and delay-sensitive multimedia application. We find that the VoIP quality at the cell center is perfect, where the value of Perceptual Evaluation of Speech Quality exceeds 4. At the cell edge, the quality is degraded but still adequate. We also observe that the downlink of mobile WiMAX network can support video streaming up to 4 Mbps with the Mean Opinion Score (MOS) value of 4.5. On the uplink, the bitrate of 1 Mbps is supported with MOS 4.5 at the cell center and with MOS 3.2 at the cell edge, respectively. Our experiments further indicate that a smooth playback of YouTube 480P video is consistently provided. Finally, the handover case has very limited impact to the overall quality degradation of both VoIP and video streaming.
An overview of quality of experience measurement challenges for video applications
- in IP networks,” in Wired/Wireless Internet Communications, ser. Lecture Notes in Computer Science
"... Abstract. The increase in multimedia content on the Internet has created a re-newed interest in quality assessment. There is however a main difference from the traditional quality assessment approaches, as now, the focus relies on the user per-ceived quality, opposed to the network centered approach ..."
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Abstract. The increase in multimedia content on the Internet has created a re-newed interest in quality assessment. There is however a main difference from the traditional quality assessment approaches, as now, the focus relies on the user per-ceived quality, opposed to the network centered approach classically proposed. In this paper we overview the most relevant challenges to perform Quality of Experi-ence (QoE) assessment in IP networks and highlight the particular considerations necessary when compared to alternative mechanisms, already deployed, such as Quality of Service (QoS). To assist on the handling of such challenges we first discuss the different approaches to Quality of Experience assessment along with the most relevant QoE metrics, and then we discuss how they are used to provide objective results about user satisfaction.
G.-M.; “Performance Evaluation of Multimedia Content Distribution Over Multi-Homed Wireless Networks
- IEEE Transactions on Broadcasting Issue
, 2011
"... Abstract—The growing availability of IP based heterogeneous wireless access technologies coupled with the increasing capabil-ities of mobile devices is creating opportunities for multimedia dis-tribution. Through its multi-homing feature, the ability to sup-port multiple network connections in a sin ..."
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Cited by 7 (3 self)
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Abstract—The growing availability of IP based heterogeneous wireless access technologies coupled with the increasing capabil-ities of mobile devices is creating opportunities for multimedia dis-tribution. Through its multi-homing feature, the ability to sup-port multiple network connections in a single end to end associ-ation, the transport layer Stream Control Transmission Protocol (SCTP) can enable seamless and transparent communication ses-sions over multiple heterogeneous networks. This paper analyzes the performance of multimedia distribution when making use of two multi-homing SCTP-based approaches: Single Path Transfer and Concurrent Multi-path Transfer, in which a single or all paths within an association are used simultaneously for data transmis-sion. In this investigation various retransmission policies and dif-ferent parameter sets are used in turn and recommendations are made for achieving best results during video delivery. In order to perform this study a novel realistic evaluation tool-set was pro-posed and is described, which can simulate video delivery over SCTP. Our simulation results and analysis show how to optimize the transmission of multimedia content over SCTP associations in both single and multipath scenarios. Index Terms—Concurrent multi-path transfer, multi-homing, multimedia distribution, SCTP, single path transfer. I.
