Video Transmission Over Wireless Channels PDF Download

Author: Negar Nejati
Publisher:
ISBN: 9781109668698
Category :
Languages : en
Pages : 112

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Book Description
Multimedia applications over wireless channels have received a great attention recently. This demand for such applications has motivated many researchers to design and provide various transmission strategies and schemes. Despite all improvements in multimedia transmission techniques and wireless network infrastructure, still many challenges exist in providing an acceptable level of Quality of Service (QoS) for these applications. In this thesis we start with looking at the distortion-optimal schemes for video trans- mission over a wireless channel. We identify an analytical expression for the expected distortion of a single layer video bitstream. Utilizing this model, we provide a low complexity Unequal Error Protection (UEP) method for transmitting the sequence over a tandem channel, considering the priority of different types of frames in the video sequence, as well as the channel conditions. Then we extend our work by considering a scalable video bitstream including both Base Layer (BL) and Enhancement Layer (EL). Assuming the BL is received free of error, we propose an expected distortion model for progressive EL. A low-complexity distortion-optimal budget allocation scheme is provided here for EL transmission over such a channel with both bit errors and packet erasures. Utilizing the provided expected models and transmission schemes, we propose an analytical expression to model a scalable video bitstream including both BL and EL bitstreams. Considering the different priority of BL and EL bitstreams, we allocate the total transmission budget among these bitstreams and transmit them with the previously proposed distortion-optimal UEP schemes over a wireless channel. In the next step, we provide a rate-optimal method for transmitting a single layer video over a Multiple Input Multiple Output (MIMO) wireless channel considering bit errors. In this part of our work, we propose a low-complexity algorithm to select the best available source rate, channel code rate and Space-Time Code (STC) to maximize the probability of bitstream recovery at the receiver side, considering the channel conditions.

Author: Chao Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 350

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Book Description
Video traffic is growing rapidly in wireless networks. Different from ordinary data traffic, video streams have higher data rates and tighter delay constraints. The ever-varying throughput of wireless links, however, cannot support continuous video playback if the video data rate is kept at a high level. To this end, adaptive video transmission techniques are employed to reduce the risk of playback interruptions by dynamically matching the video data rate to the varying channel throughput. In this dissertation, I develop new models to capture viewers' quality of experience (QoE) and design adaptive transmission algorithms to optimize the QoE. The contributions of this dissertation are threefold. First, I develop a new model for the viewers' QoE in rate-switching systems in which the video source rate is adapted every several seconds. The model is developed to predict an important aspect of QoE, the time-varying subjective quality (TVSQ), i.e., the up-to-the-moment subjective quality of a video as it is played. I first build a video database of rate-switching videos and measure TVSQs via a subjective study. Then, I parameterize and validate the TVSQ model using the measured TVSQs. Finally, based on the TVSQ model, I design an adaptive rate-switching algorithm that optimizes the time-averaged TVSQs of wireless video users. Second, I propose an adaptive video transmission algorithm to optimize the Overall Quality (OQ) of rate-switching videos, i.e., the viewers' judgement on the quality of the whole video. Through the subjective study, I find that the OQ is strongly correlated with the empirical cumulative distribution function (eCDF) of the video quality perceived by viewers. Based on this observation, I develop an adaptive video transmission algorithm that maximizes the number of video users who satisfy given constraints on the eCDF of perceived video qualities. Third, I propose an adaptive transmission algorithm for scalable videos. Different from the rate-switching systems, scalable videos support rate adaptation for each video frame. The proposed adaptive transmission algorithm maximizes the time-averaged video quality while maintaining continuous video playback. When the channel throughput is high, the algorithm increases the video data rate to improve video quality. Otherwise, the algorithm decreases the video data rate to buffer more videos and to reduce the risk of playback interruption. Simulation results show that the performance of the proposed algorithm is close to a performance upper bound.

Author: Bhumin Pathak
Publisher: LAP Lambert Academic Publishing
ISBN: 9783848493074
Category :
Languages : en
Pages : 308

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Book Description
A variety of applications range from simple web-browsing to real time video transmission in unicast or multicast modes are widely used over different wireless communication services. Error prone and bandwidth limited wireless environment presents a specific set of challenges to terrestrial radio mobile communication system such as UMTS to provide enhanced end-user service experience. In this presented research, some of the problems related to transmission error for a video application over a UMTS wireless environment are investigated. Compression algorithm required to utilize bandwidth effectively converts independent raw video frames into a highly hierarchical structure with introduction of coding dependences between frames. A transmission error can result into significant error propagation over successive frames degrading the quality of the received video sequence. The problem of error propagation in compressed video sequence transmitted over UMTS mobile radio network is identified, quantified and addressed in this book

Author: Qinqing Zhang
Publisher:
ISBN:
Category :
Languages : en
Pages : 166

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Book Description

Author: Fan Zhai
Publisher: Morgan & Claypool Publishers
ISBN: 1598290452
Category : Technology & Engineering
Languages : en
Pages : 148

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Book Description
This book deals with the problem of joint source-channel video transmission, i.e., the joint optimal allocation of resources at the application layer and the other network layers, such as data rate adaptation, channel coding, power adaptation in wireless networks, quality of service (QoS) support from the network, and packet scheduling, for efficient video transmission. Real-time video communication applications, such as videoconferencing, video telephony, and on-demand video streaming, have gained increased popularity. However, a key problem in video transmission over the existing Internet and wireless networks is the incompatibility between the nature of the network conditions and the QoS requirements (in terms, for example, of bandwidth, delay, and packet loss) of real-time video applications. To deal with this incompatibility, a natural approach is to adapt the end-system to the network. The joint source-channel coding approach aims to efficiently perform content-aware cross-layer resource allocation, thus increasing the communication efficiency of multiple network layers. Our purpose in this book is to review the basic elements of the state-of-the-art approaches toward joint source-channel video transmission for wired and wireless systems. In this book, we present a general resource-distortion optimization framework, which is used throughout the book to guide our discussions on various techniques of joint source-channel video transmission. In this framework, network resources from multiple layers are assigned to each video packet according to its level of importance. It provides not only an optimization benchmark against which the performance of other sub-optimal systems can be evaluated, but also a useful tool for assessing the effectiveness of different error control components in practical system design. This book is therefore written to be accessible to researchers, expert industrial R&D engineers, and university students who are interested in the cutting edge technologies in joint source-channel video transmission. Contents: Introduction / Elements of a Video Communication System / Joint Source-Channel Coding / Error-Resilient Video Coding / Channel Modeling and Channel Coding / Internet Video Transmission / Wireless Video Transmission / Conclusions

Author: Siyuan Xiang
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
With the increasing demand of video applications in wireless networks, how to better support video transmission over wireless networks has drawn much attention to the research community. Time-varying and error-prone nature of wireless channel makes video transmission in wireless networks a challenging task to provide the users with satisfactory watching experience. For different video applications, we choose different video coding techniques accordingly. E.g., for Internet video streaming, we choose standardized H.264 video codec; for video transmission in sensor networks or multicast, we choose simple and energy-conserving video coding technique based on compressive sensing. Thus, the challenges for different video transmission applications are different. Therefore, This dissertation tackles video transmission problem in three different applications. First, for dynamic adaptive streaming over HTTP (DASH), we investigate the streaming strategy. Specifically, we focus on the rate adaptation algorithm for streaming scalable video (H.264/SVC) in wireless networks. We model the rate adaptation problem as a Markov Decision Process (MDP), aiming to find an optimal streaming strategy in terms of user-perceived quality of experience (QoE) such as playback interruption, average playback quality and playback smoothness. We then obtain the optimal MDP solution using dynamic programming. However, the optimal solution requires the knowledge of the available bandwidth statistics and has a large number of states, which makes it difficult to obtain the optimal solution in real time. Therefore, we further propose an online algorithm which integrates the learning and planning process. The proposed online algorithm collects bandwidth statistics and makes streaming decisions in real time. A reward parameter has been defined in our proposed streaming strategy, which can be adjusted to make a good trade-off between the average playback quality and playback smoothness. We also use a simple testbed to validate our proposed algorithm. Second, for video transmission in wireless sensor networks, we consider a wireless sensor node monitoring the environment and it is equipped with a compressive-sensing based, single-pixel image camera and other sensors such as temperature and humidity sensors. The wireless node needs to send the data out in a timely and energy efficient way. This transmission control problem is challenging in that we need to jointly consider perceived video quality, quality variation, power consumption and transmission delay requirements, and the wireless channel uncertainty. We address the above issues by first building a rate-distortion model for compressive sensing video. Then we formulate the deterministic and stochastic optimization problems and design the transmission control algorithm which jointly performs rate control, scheduling and power control. Third, we propose a low-complex, scalable video coding architecture based on compressive sensing (SVCCS) for wireless unicast and multicast transmissions ...

Author: Ce Zhu
Publisher: CRC Press
ISBN: 1351832743
Category : Computers
Languages : en
Pages : 523

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Book Description
Wireless video communications encompass a broad range of issues and opportunities that serve as the catalyst for technical innovations. To disseminate the most recent advances in this challenging yet exciting field, Advanced Video Communications over Wireless Networks provides an in-depth look at the fundamentals, recent technical achievements, challenges, and emerging trends in mobile and wireless video communications. The editors have carefully selected a panel of researchers with expertise in diverse aspects of wireless video communication to cover a wide spectrum of topics, including the underlying theoretical fundamentals associated with wireless video communications, the transmission schemes tailored to mobile and wireless networks, quality metrics, the architectures of practical systems, as well as some novel directions. They address future directions, including Quality-of-Experience in wireless video communications, video communications over future networks, and 3D video communications. The book presents a collection of tutorials, surveys, and original contributions, providing an up-to-date, accessible reference for further development of research and applications in mobile and wireless video communication systems. The range of coverage and depth of expertise make this book the go-to resource for facing current and future challenges in this field.

Author: Shengjie Zhao
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Compressed video bitstream transmissions over wireless networks are addressed in this work. We first consider error control and power allocation for transmitting wireless video over CDMA networks in conjunction with multiuser detection. We map a layered video bitstream to several CDMA fading channels and inject multiple source/parity layers into each of these channels at the transmitter. We formulate a combined optimization problem and give the optimal joint rate and power allocation for each of linear minimum mean-square error (MMSE) multiuser detector in the uplink and two types of blind linear MMSE detectors, i.e., the direct-matrix-inversion (DMI) blind detector and the subspace blind detector, in the downlink. We then present a multiple-channel video transmission scheme in wireless CDMA networks over multipath fading channels. For a given budget on the available bandwidth and total transmit power, the transmitter determines the optimal power allocations and the optimal transmission rates among multiple CDMA channels, as well as the optimal product channel code rate allocation. We also make use of results on the large-system CDMA performance for various multiuser receivers in multipath fading channels. We employ a fast joint source-channel coding algorithm to obtain the optimal product channel code structure. Finally, we propose an end-to-end architecture for multi-layer progressive video delivery over space-time differentially coded orthogonal frequency division multiplexing (STDC-OFDM) systems. We propose to use progressive joint source-channel coding to generate operational transmission distortion-power-rate (TD-PR) surfaces. By extending the rate-distortion function in source coding to the TD-PR surface in joint source-channel coding, our work can use the 'equal slope' argument to effectively solve the transmission rate allocation problem as well as the transmission power allocation problem for multi-layer video transmission. It is demonstrated through simulations that as the wireless channel conditions change, these proposed schemes can scale the video streams and transport the scaled video streams to receivers with a smooth change of perceptual quality.

Author: King N. Ngan
Publisher: CRC Press
ISBN: 148229009X
Category : Technology & Engineering
Languages : en
Pages : 560

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Book Description
"Explains the transmission of image and video information over wireless channels. Describes MPEG-4, the latest video coding standard. Discusses error resilient combined source channel image and video coders, and multiple access spread spectrum and future generation wireless video communication systems."

Author: Fan Zhai
Publisher: Morgan & Claypool Publishers
ISBN: 1598290444
Category : Coding theory
Languages : en
Pages : 149

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Book Description
Examines the problem of joint source-channel video transmission - the joint optimal allocation of resources at the application layer and the other network layers, such as data rate adaptation, channel coding, power adaptation in wireless networks, quality of service (QoS) support from the network, and packet scheduling, for efficient video transmission.