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Error-resilient video streaming over wireless networks using combined scalable coding and multiple-description coding

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2007年第4期22卷 403-420页

作者： Chen, Chih-Ming Chen, Chien-Min Lin, Chia-Wen Chen, Yung-Chang Natl Tsing Hua Univ Dept Elect Engn Hsinchu 300 Taiwan Chunghwa Telecom Co Ltd Telecommun Labs Tao Yuan 326 Taiwan

In this paper, we propose a novel error-resilient coding technique, namely, multiple-description fine granularity scalability (MD-FGS) coding, to enhance error resiliency while retaining good temporal prediction efficiency for video transport over error-prone networks, especially for wireless channels. The proposed MD-FGS coding scheme is based on a combination of FGS and modified MD scalar quantization (MDSQ), named Base-MDSQ, in which partial prediction is utilized to control drifting error. We also propose an adaptive soft handoff algorithm to effectively mitigate video quality degradation caused by transient channel switching when a mobile client roams in wireless local area networks (WLANs). The handoff algorithm utilizes a channel estimator to decide which channels should be used for delivering video. Experimental results show that the proposed method effectively mitigates error propagation due to packet loss while maintaining good coding efficiency. (C) 2007 Elsevier B.V. All rights reserved.

关键词： video streaming error-resilient coding transcoding scalable coding path diversity multiple-description coding channel handoff

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LSP-based multiple-description coding for real-time low bit-rate voice over IP

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IEEE TRANSACTIONS ON MULTIMEDIA 2005年第1期7卷 167-178页

作者： Wah, BW Lin, D Univ Illinois Dept Elect & Comp Engn Urbana IL 61801 USA Univ Illinois Coordinated Sci Lab Urbana IL 61801 USA

A fundamental issue in real-time interactive voice transmissions over unreliable IP networks is the loss or late arrival of packets for playback. This problem is especially serious when transmitting low bit rate-coded speech with pervasive dependencies introduced. In this case, the loss or late arrival of a single packet will lead to the loss of subsequent dependent frames. In this paper, we study end-to-end loss-concealment schemes for ensuring high quality in playback. We propose a novel multiple description-coding method for concealing packet losses in transmitting low bit rate-coded speech. Based on high correlations observed in linear predictor parameters-in the form of Line Spectral Pairs (LSPs)-of adjacent frames, we generate multiple descriptions in senders by interleaving LSPs, and reconstruct lost LSPs in receivers by linear interpolations. As excitation codewords have low correlations, we further enlarge the segment size for excitation generation and replicate excitation codewords in all the descriptions in order to maintain the same transmission bandwidth. Our proposed scheme can be extended easily to more than two descriptions and can adapt its number of descriptions dynamically to network-loss conditions. Experimental results on FS-1016 CELP, ITU G.723.1, and FS MELP coders show good performance of our scheme.

关键词： Internet Line Spectral Pairs loss concealment low bit-rate speech coding multiple-description coding single-description coding UDP voice over IP

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PREDICTIVE POWER CONTROL AND multiple-description coding FOR WIRELESS SENSOR NETWORKS

PREDICTIVE POWER CONTROL AND MULTIPLE-DESCRIPTION CODING FOR...

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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Ostergaard, Jan Quevedo, Daniel E. Ahlen, Anders Aalborg Univ Dept Elect Syst Aalborg Denmark Univ Newcastle Sch Elect Engn & Comp Sci Newcastle NSW Australia Uppsala Univ Dept Engn Sci Signals & Syst Uppsala Sweden

ISBN: (纸本)9781424423538

We study state estimation via wireless sensor networks over fading channels affected by random packet loss. In the configuration examined, the sensors send their measurements to a single gateway, which decides upon the source coding scheme and the sensor transmitter power levels. The decision process is carried out on-line and adapts to changing channel conditions to achieve an optimal trade-off between estimation quality and sensor energy expenditure. In particular, if some channel conditions are poor, then the gateway commands the corresponding sensors to increase power levels and use multiple-description coding. Simulations based on measured channel data illustrate that the proposed scheme gives excellent results.

关键词： wireless sensor networks power control multiple-description coding

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Real-Time Perceptual Moving-Horizon multiple-description Audio coding

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2011年第9期59卷 4286-4299页

作者： Ostergaard, Jan Quevedo, Daniel E. Jensen, Jesper Aalborg Univ Dept Elect Syst DK-9220 Aalborg Denmark Univ Newcastle Sch Elect Engn & Comp Sci Callaghan NSW 2308 Australia Oticon DK-9220 Copenhagen Denmark

A novel scheme for perceptual coding of audio for robust and real-time communication is designed and analyzed. As an alternative to PCM, DPCM, and more general noise-shaping converters, we propose to use psychoacoustically optimized noise-shaping quantizers based on the moving-horizon principle. In moving-horizon quantization, a few samples look-ahead is allowed at the encoder, which makes it possible to better shape the quantization noise and thereby reduce the resulting distortion over what is possible with conventional noise-shaping techniques. It is first shown that significant gains over linear PCM can be obtained without introducing a delay and without requiring postprocessing at the decoder, i.e., the encoded samples can be stored as, e. g., 16-bit linear PCM on CD-ROMs, and played out on standards-compliant CD players. We then show that multiple-description coding can be combined with moving-horizon quantization in order to combat possible erasures on the wireless link without introducing additional delays.

关键词： Low delay source coding moving horizon quantization multiple-description coding perceptual audio coding

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LOW DELAY MOVING-HORIZON multiple-description AUDIO coding FOR WIRELESS HEARING AIDS

LOW DELAY MOVING-HORIZON MULTIPLE-DESCRIPTION AUDIO CODING F...

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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Ostergaard, Jan Quevedo, Daniel E. Jensen, Jesper Aalborg Univ Dept Elect Syst Aalborg Denmark Univ Newcastle Sch Elect Engn & Comp Sci Newcastle NSW Australia Oticon Copenhagen Denmark

ISBN: (纸本)9781424423538

In this work, we construct a novel scheme for efficient perceptual coding of audio for robust communication between encoders and wireless hearing aids. To limit the physical size of the hearing aids and to reduce power consumption and thereby increase the lifetime expectancy of the batteries, the hearing aids are constrained to be of low complexity. We therefore provide an asymmetric strategy where most of the computational load is placed at the encoding side. We make use of multiple-description coding. This combats possible erasures on the wireless link between the encoder and the hearing aids without introducing significant delay. Furthermore, we employ psychoacoustically optimized noise-shaping quantizers based on the moving-horizon principle, which exploits a finite prediction horizon.

关键词： multiple-description coding noise shaping perceptual audio coding low delay source coding

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Unbalanced multiple-description video coding with rate-distortion optimization

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2003年第1期2003卷 81-90页

作者： Comas, D Singh, R Ortega, A Marqués, F Tech Univ Catalonia Dept Signal Theory & Commun Image Proc Grp Barcelona 08034 Spain Indian Inst Technol IBM India Res Lab New Delhi India Univ So Calif Dept Elect Engn Inst Signal & Image Proc Los Angeles CA 90089 USA Univ So Calif Dept Elect Engn Integrated Media Syst Ctr Los Angeles CA 90089 USA

We propose to use multiple-description coding (MDC) to protect video information against packet losses and delay, while also ensuring that it can be decoded using a standard decoder. Video data a re encoded into a high-resolution stream using a standard compliant encoder. In addition, a low-resolution stream is generated by duplicating the relevant information (motion vectors, headers and some of the DCT coefficient) from the high-resolution stream while the remaining coefficients are set to zero. Both streams are independently decodable by a standard decoder. However, only in case of losses in the high resolution description, the corresponding information from the low resolution stream is decoded;else the received high resolution description is decoded. The main contribution of this paper is an optimization algorithm which, given the loss ratio, allocates bits to both descriptions and selects the right number of coefficients to duplicate in the low-resolution stream so as to minimize the expected distortion at the decoder end.

关键词： multiple-description coding robust video transmission rate-distortion optimization packet networks

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multiple-description predictive-vector quantization with applications to low bit-rate speech coding over networks

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IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2007年第3期15卷 749-755页

作者： Yahampath, Pradeepa Rondeau, Paul Univ Manitoba Dept Elect & Comp Engn Winnipeg MB R3T 5V6 Canada

An algorithm for designing linear prediction-based two-channel multiple-description predictive-vector quantizers;(MD-PVQs) for packet-loss channels is presented. This algorithm iteratively improves the encoder partition, the set of multiple description codebooks, and the linear predictor for a given channel loss probability, based on a training set of source data. The effectiveness of the designs obtained with the given algorithm is demonstrated using a waveform coding example involving a Markov source as well as vector quantization of speech line' spectral pairs.

关键词： multiple-description coding predictive coding speech coding vector quantization

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Power Control and coding Formulation for State Estimation With Wireless Sensors

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IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY 2014年第2期22卷 413-427页

作者： Quevedo, Daniel E. Ostergaard, Jan Ahlen, Anders Univ Newcastle Sch Elect Engn & Comp Sci Callaghan NSW 2308 Australia Aalborg Univ Dept Elect Syst DK-9220 Aalborg Denmark Uppsala Univ S-75121 Uppsala Sweden

Technological advances made wireless sensors cheap and reliable enough to be brought into industrial use. A major challenge arises from the fact that wireless channels introduce random packet dropouts. Power control and coding are key enabling technologies in wireless communications to ensure efficient communication. In this paper, we examine the role of power control and coding for Kalman filtering over wireless correlated channels. Two estimation architectures are considered;initially, the sensors send their measurements directly to a single gateway (GW). Next, wireless relay nodes provide additional links. The GW decides on the coding scheme and the transmitter power levels of the wireless nodes. The decision process is carried out online and adapts to varying channel conditions to improve the tradeoff between state estimation accuracy and energy expenditure. In combination with predictive power control, we investigate the use of multiple-description coding (MDC), zero-error coding (ZEC), and network coding and provide sufficient conditions for the expectation of the estimation error covariance matrix to be bounded. Numerical results suggest that the proposed method may lead to energy savings of around 50%, when compared with an alternative scheme, wherein transmission power levels and bit-rates are governed by simple logic. In particular, ZEC is preferable at time instances with high channel gains, whereas MDC is superior for time instances with low gains. When channels between the sensors and the GW are in deep fades, network coding improves estimation accuracy significantly without sacrificing energy efficiency.

关键词： Distributed source coding Kalman filtering multiple-description coding network coding power control relays wireless sensors (WSs)

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From Centralized to Decentralized Video Streaming Using multiple descriptions coding

From Centralized to Decentralized Video Streaming Using Mult...

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International Symposium on Ubiquitous Multimedia Computing (UMC-08)

作者： Lee, Ivan He, Yifeng Guan, Lino Univ S Australia Sch Comp & Informat Engn Mawson Lakes SA 5095 Australia Ryerson Polytech Inst Dept Elect & Comp Engn Toronto ON M5B 2K3 Canada

ISBN: (纸本)9780769534275

In this paper, we examine the frame loss probabilities for multiple-description coded (MDC) video transmitted over independent paths. We apply an efficient multiple description coding technique for the analysis, and we investigate the impact or drifting error in terms of the probability of receiving freeze frames for reconstructed video. The performance of centralized and decentralized Peer-to-Peer streaming are studied in this paper. This paper highlights the attributes of the lost traffic among centralized server and distributed P2P nodes, and a strategy to stabilize the frame loss rate by varying the Group-of-Picture length according to the number of MDC substreams is also presented in this paper.

关键词： Peer-to-Peer video streaming multiple-description coding

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A negotiation framework for content distribution in mobile transient networks

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JOURNAL OF NETWORK AND COMPUTER APPLICATIONS 2009年第5期32卷 1000-1011页

作者： Molina, Benjamin Pileggi, Salvatore F. Esteve, Manuel Palau, Carlos E. Univ Politecn Valencia Dept Commun Valencia 46022 Spain

Transient networks are spontaneous networks that appear for a short period of time in order to provide basic services Such as connectivity and content distribution among a small community. Nowadays mobile devices are becoming multimode by nature providing multiple connection paths. This paper investigates the efficiency and benefit of a mobile transient network where multiple nodes collaborate, offering a multihomed network with community set-vices by means of intelligent agents. The paper concretely proposes an architecture able to fully Support a peer-to-peer transient community during both negotiation and service steps for two different modes: file download and multimedia streaming. The first mode, implemented on intelligent and cooperative agents, provides two negotiation models (fair and dynamic) in order to guarantee wider flexibility for different possible scenarios and community models;the second one implements a content delivery system into transient community, taking advantage Of multihomed features of mobile devices. (C) 2009 Elsevier Ltd. All rights reserved.

关键词： Distributed and mobile transient network Social network Peer-to-peer Web semantic Intelligent agents multiple-description coding

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