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Lossy Multicasting Over Binary Symmetric Broadcast channels

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2011年第8期59卷 3915-3929页

作者： Bursalioglu, Ozgun Y. Fresia, Maria Caire, Giuseppe Poor, H. Vincent Univ So Calif Ming Hsieh Dept Elect Engn Los Angeles CA 90089 USA Intel Mobile Commun Munich Germany Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

Lossy multicasting of a set of independent, discrete-time, continuous-amplitude source components under the mean square error distortion measure over binary symmetric broadcast channels is investigated. The practically appealing concatenation of successive refinement source coding with broadcast coding and, specifically, time-sharing of linear binary codes, is considered. Three different system optimization criteria are formulated for the lossy multicasting problem. The resulting system optimization is fairly general and applies to a variety of combinations of successive refinement source codes and channel codes. The system optimization is investigated in depth for a class of channel optimized quantization with successive refinement, obtained by using standard embedded scalar quantizers and linear mapping of the (redundant) quantizer bitplanes onto channel codewords by using a systematic Raptor encoder. This scheme is referred to as quantization with linear index coding (QLIC). Unlike existing literature on progressive transmission with unequal error protection or channel optimized quantization, the focus here is on the regime of moderate-to-large code block length and the power of modern sparse-graph codes with iterative belief propagation decoding is leveraged. In this regime, the system optimization takes on the form of simple convex programming that reduces to linear programming for QLIC. The performance of QLIC compares favorably with respect to the state of the art channel optimized quantization in the conventional setting of a single Gaussian source over a binary symmetric channel. For the multicast scenario, the performance gap incurred by the practical QLIC design with respect to ideal source and channel codes is quantified.

关键词： Block codes channel-optimized quantization multicast communication rateless codes source-channel coding

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Advances in channel-adaptive video streaming

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WIRELESS COMMUNICATIONS & MOBILE COMPUTING 2002年第6期2卷 573-584页

作者： Girod, B Kalman, M Liang, YJ Zhang, R Stanford Univ Dept Elect Engn Informat Syst Lab Stanford CA 94305 USA

Despite the well-known challenges of variations in throughput, delay, and packet loss over the Internet, video streaming has experienced phenomenal growth, owing to the extensive research in video coding and transmission. In this paper, we review several recent advances for channel-adaptive video streaming that, we believe, will benefit the design of video streaming systems in the future. Employed in different components of the system, these techniques have the common objective of providing efficient, robust, scalable, and low-latency streaming video. Firstly, by allowing the client to control the rate at which it consumes data, adaptive media playout can be used to reduce receiver buffering and therefore average latency, and provide limited rate scalability. Secondly, rate-distortion optimized packet scheduling, a transport technique, provides a flexible framework to determine the best packet to send, given the channel behaviors, the packets' deadlines, their transmission histories, the distortion reduction associated with sending each packet, and the interpacket dependencies. Thirdly, at the source encoder, channel-adaptive packet-dependency control can greatly improve the error resilience of streaming video and reduce latency. Finally, we address the specific additional challenges for wireless video streaming. We consider three architectures for wireless video and discuss the utility of the reviewed techniques for each architecture. Copyright (C) 2002 John Wiley Sons, Ltd.

关键词： multimedia communication video streaming wireless video error-resilient video coding low latency rate distortion scalability source-channel coding

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Reconstruction of Correlated sources With Energy Harvesting Constraints in Delay-Constrained and Delay-Tolerant Communication Scenarios

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2017年第3期16卷 1974-1986页

作者： Calvo-Fullana, Miguel Matamoros, Javier Anton-Haro, Carles Ctr Tecnol Telecomunicac Catalunya Barcelona 08860 Spain

In this paper, we investigate the reconstruction of time-correlated sources in a point-to-point communications scenario comprising an energy-harvesting sensor and a Fusion Center (FC). Our goal is to minimize the average distortion in the reconstructed observations by using data from previously encoded sources as side information. First, we analyze a delay-constrained scenario, where the sources must be reconstructed before the next time slot. We formulate the problem in a convex optimization framework and derive the optimal transmission (i.e., power and rate allocation) policy. To solve this problem, we propose an iterative algorithm based on the subgradient method. Interestingly, the solution to the problem consists of a coupling between a 2-D directional water-filling algorithm (for power allocation) and a reverse water-filling algorithm (for rate allocation). Then, we find a more general solution to this problem in a delay-tolerant scenario where the time horizon for source reconstruction is extended to multiple time slots. Finally, we provide some numerical results that illustrate the impact of delay and correlation in the power and rate allocation policies, and in the resulting reconstruction distortion. We also discuss the performance gap exhibited by a heuristic online policy derived from the optimal (offline) one.

关键词： Energy harvesting wireless sensor networks source-channel coding distortion

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Variational Learned Talking-Head Semantic Coded Transmission System

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China Communications 2024年第7期21卷 37-49页

作者： Yue Weijie Si Zhongwei Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Video transmission requires considerable bandwidth,and current widely employed schemes prove inadequate when confronted with scenes featuring *** by the strides in talkinghead generative technology,the paper introduces a semantic transmission system tailored for talking-head *** system captures semantic information from talking-head video and faithfully reconstructs source video at the receiver,only one-shot reference frame and compact semantic features are required for the entire ***,we analyze video semantics in the pixel domain frame-by-frame and jointly process multi-frame semantic information to seamlessly incorporate spatial and temporal *** modeling is utilized to evaluate the diversity of importance among group semantics,thereby guiding bandwidth resource allocation for semantics to enhance system *** whole endto-end system is modeled as an optimization problem and equivalent to acquiring optimal rate-distortion *** evaluate our system on both reference frame and video transmission,experimental results demonstrate that our system can improve the efficiency and robustness of *** to the classical approaches,our system can save over 90%of bandwidth when user perception is close.

关键词： semantic communications source-channel coding talking-head transmission variational modeling

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Optimal error protection for real-time image and video transmission

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IEEE SIGNAL PROCESSING LETTERS 2004年第10期11卷 780-783页

作者： Farshchian, M Cho, S Pearlman, WA Rensselaer Polytech Inst Ctr Image Proc Res Dept Elect Comp & Syst Engn Troy NY 12180 USA

In this letter, a novel and computationally inexpensive analytic mean square error (mse) distortion rate (D-R) estimator for SPIHT which generates a nearly exact D-R function for the two- and three-dimensional SPIHT algorithm is presented. Utilizing our D-R estimate, we employ unequal error protection and equal error protection. in order to minimize the end to end mse distortion of the transform domain. A major contribution of this letter is the simple and extremely accurate analytical D-R model which potentially improves upon pre-existing methodologies and applications that rely on an accurate and computationally inexpensive D-R estimate.

关键词： image transmission source-channel coding SPIHT video transmission wireless transmission

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Two-Way Gaussian Networks With a Jammer and Decentralized Control

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IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS 2020年第1期7卷 446-457页

作者： McDonald, Curtis Alajaji, Fady Yuksel, Serdar Queens Univ Dept Math & Stat Kingston ON K7L 3N6 Canada

We consider the existence and structure of (zero-sum game) Nash equilibria for a two-way network in the presence of an intelligent jammer capable of tapping the channel signals in both directions. We assume that the source and channel noise signals are all Gaussian random variables, where the source signals are independent of each other, while the noise signals are arbitrarily correlated. We show that for fixed jammer power constraints, a Nash equilibrium exists with respect to the system wide mean square error, and equilibrium jamming policies are always Gaussian. We derive the equilibrium policies in closed form under various system parameters. Finally for two system scenarios, we analytically determine the optimal power allocation levels the jammer can deploy in each channel link, when allowed to operate under an overall power constraint.

关键词： Decentralized signaling and estimation game theory information theory source-channel coding two-way Gaussian networks

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The Gaussian source-and-Data-Streams Problem

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IEEE TRANSACTIONS ON COMMUNICATIONS 2019年第8期67卷 5618-5628页

作者： Bross, Shraga, I Lapidoth, Amos Bar Ilan Univ Fac Engn IL-52900 Ramat Gan Israel Swiss Fed Inst Technol CH-8092 Zurich Switzerland

A Gaussian source and two data streams are to be transmitted over a Gaussian broadcast channel: the first stream, the "common stream," is to be decoded by both receivers, and the second, the "private stream," only by the strong receiver. Both receivers wish to estimate the source sequence, though with possibly different mean squared-errors. The quadruples of achievable rates and estimation errors are characterized, and it is shown that-once the data rates have been fixed-there is no tension between the estimation errors. Only the "equal bandwidth" case is treated, where the rate at which the source emits symbols is also the rate at which the channel is used.

关键词： Gaussian broadcast channel Gaussian source mean squared-error source-channel coding

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A Joint source-channel Rate-Distortion Optimization Algorithm for H.264 Codec in Wireless Networks

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13th International-Computer-Society-of-Iran-Computer Conference

作者： Rasouli, Razieh Rabiee, Hamid R. Ghanbari, Mohammad Sharif Univ Technol Dept Comp Engn AICTC Res Ctr Tehran Iran

ISBN: (纸本)9783540899846

In recent years, the demand for video transmission over wireless communication networks is growing very fast. The H.264 video compression standard which offers high quality at low bit rates, is a suitable codec for applications that require efficient video transmission over wireless networks. While the compressed videos are transmitted through error-prone networks, error robustness becomes an important issue. In this paper, a joint source-channel Lagrange optimization method in which the distortion of the decoder is estimated without using feedback which can be used for both multicast and point-to-point applications is proposed. The experimental results show that the new algorithm has a good performance in video transmission over error-prone channels by concealing the lost packets at the decoder.

关键词： Wireless Networks H.264 Lagrange Rate-Distortion Optimization source-channel coding

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Reduced complexity algorithm for channel optimized switched split vector quantization: Application to wideband LSF parameters

Reduced complexity algorithm for channel optimized switched ...

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IEEE Jordan Conference on Applied Electrical Engineering and Computing Technologies (AEECT)

作者： Salah-Eddine, Cheraitia Bouzid, Merouane USTHB Univ Elect Fac Dept Telecommun Algiers Algeria

ISBN: (纸本)9781479923052;9781479923038

In this paper, a reduced complexity stochastic joint source-channel coding system is proposed for efficient and robust coding of wideband speech LSF (Line Spectral Frequencies) parameters. The aim of the initial version of this system was to achieve a transparent quantization quality of LSF parameters under noiseless channel conditions. It was developed based on the switched split vector quantization (SSVQ) technique and called "LSF-SSVQ coder". After that, we were interested on the improvement of the LSF-SSVQ coder robustness for real transmissions over a noisy channel. To protect implicitly our wideband LSF encoders, we developed a non-redundant joint source-channel coding system based on a reduced complexity stochastic version of the channel optimized SSVQ technique.

关键词： SSVQ Quantization source-channel coding robust speech coding LSF parameters

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source-optimized irregular repeat accumulate codes with inherent unequal error protection capabilities and their application to scalable image transmission

Source-optimized irregular repeat accumulate codes with inhe...

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37th Asilomar Conference on Signals, Systems and Computers

作者： Lan, Ching-Fu Xiong, Zixiang Narayanan, Krishna R. Texas A&M Univ Dept Elect & Comp Engn College Stn TX 77843 USA

The common practice for achieving unequal error protection (UEP) in scalable multimedia communication systems is to design rate-compatible punctured channel codes before computing the UEP rate assignments. This paper proposes a new approach to designing powerful irregular repeat accumulate (IRA) codes that are optimized for the multimedia source and to exploiting the inherent irregularity in IRA codes for UEP. Using the end-to-end distortion due to the first error bit in channel decoding as the cost function, which is readily given by the operational distortion-rate function of embedded source codes, we incorporate this cost function into the channel code design process via density evolution and obtain IRA codes that minimize the average cost function instead of the usual probability of error. Because the resulting IRA codes have inherent UEP capabilities due to irregularity, the new IRA code design effectively integrates channel code optimization and UEP rate assignments, resulting in source-optimized channel coding or joint source-channel coding. We simulate our source-optimized IRA codes for transporting SPIHT-coded images over a binary symmetric channel with crossover probability p. When p = 0.03 and the channel code length is long (e.g., with one codeword for the whole 512 x 512 image), we are able to operate at only 9.38% away from the channel capacity with code length 132380 bits, achieving the best published results in terms of average peak signal-to-noise ratio (PSNR). Compared to conventional IRA code design (that minimizes the probability of error) with the same code rate, the performance gain in average PSNR from using our proposed source-optimized IRA code design is 0.8759 dB when p = 0.1 and the code length is 12800 bits. As predicted by Shannon's separation principle, we observe that this performance gain diminishes as the code length increases.

关键词： irregular repeat accumulate (IRA) codes scalable source coding source-channel coding source-optimized channel coding unequal error protection (UEP)

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