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A Watermarking Method for Digital Speech Self-Recovery

IEEE-ACM TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2015年第11期23卷 1917-1925页

作者： Sarreshtedari, Saeed Akhaee, Mohammad Ali Abbasfar, Aliazam Univ Tehran Dept Elect & Comp Engn Coll Engn Tehran *** Iran

Authentication and tampering detection of the digital signals is one of the main applications of the digital watermarking. Recently, watermarking algorithms for digital images are developed to not only detect the image tampering, but also to recover the lost content to some extent. In this paper, a new watermarking scheme is introduced to generate digital self-embedding speech signals enjoying the self-recovery feature. For this purpose, the compressed version of the speech signal generated by a speech codec and protected against the tampering by the proper channel coding is embedded into the original speech signal. Experimental results show that the self-embedding speech signal is recoverable with proper speech quality for high tampering rates, without significant loss in the quality of the original speech signal.

关键词： Digital speech self-recovery digital speech watermarking source-channel coding speech authentication

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Hybrid Digital-Analog Codes for source-channel Broadcast of Gaussian sources Over Gaussian channels

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IEEE TRANSACTIONS ON INFORMATION THEORY 2011年第7期57卷 4573-4588页

作者： Prabhakaran, Vinod M. Puri, Rohit Ramchandran, Kannan Ecole Polytech Fed Lausanne CH-1015 Lausanne Switzerland Cisco Syst Inc San Jose CA 95134 USA Univ Calif Berkeley Dept EECS Wireless Fdn Berkeley CA 94702 USA

The problem of broadcasting a parallel Gaussian source over an additive white Gaussian noise broadcast channel under the mean-squared error distortion criterion is studied. A hybrid digital-analog coding strategy which combines source coding with side information, channel coding with side information, layered source coding, and superposition broadcast channel coding is presented. When specialized to the open problem of broadcasting a white Gaussian source over an additive white Gaussian noise broadcast channel with bandwidth mismatch, which has been the subject of several previous investigations, this coding scheme strictly improves on the state of the art.

关键词： Bandwidth mismatch broadcast channel dirty-paper coding Gel'fand-Pinsker hybrid-digital-analog MMSE estimation parallel Gaussian source source broadcasting source-channel coding Wyner-Ziv

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

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2006年第7期15卷 1740-1750页

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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Jointly Optimized Mode Decisions in Redundant Video Streaming

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2011年第4期21卷 513-518页

作者： Schmidt, J. Christian Rose, Kenneth Univ Calif Santa Barbara Dept Elect & Comp Engn Santa Barbara CA 93106 USA

This letter investigates source-channel coding for error-resilient video streaming using redundant encoding. We estimate the end-to-end distortion per redundantly encoded macroblock (MB) via extension of the recursive optimal per-pixel estimate to encompass redundant transmissions. Redundant encoding is formulated as joint optimization of the MB parameters in the primary and redundant transmissions. We present three encoding strategies with different gain-complexity tradeoffs. The proposed methods are general in nature, and could be implemented on top of any (hybrid) video codec. Simulation results employing H.264's redundant slice mechanism show significant performance gains over conventional error-resilient encoding methods and naive redundant encoding schemes.

关键词： Error resilience H.264 redundant slices source-channel coding video streaming

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Robust coding of wideband speech immittance spectral frequencies

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SPEECH COMMUNICATION 2014年 65卷 94-108页

作者： Salah-Eddine, Cheraitia Merouane, Bouzid USTHB Elect Fac Speech Commun & Signal Proc Lab Algiers 16111 Algeria

In this paper, we propose a reduced complexity stochastic joint source-channel coding system developed for efficient and robust coding of wideband speech ISF (Immittance Spectral Frequency) parameters. Initially, the aim of this encoding system was to achieve a transparent quantization of ISF parameters for ideal transmissions over a noiseless channels. It was designed based on the switched split vector quantization (SSVQ) technique and called "ISF-SSVQ coder". After that, our interest was drawn to the improvement of the ISF-SSVQ robustness for transmissions over a noisy channel. To protect implicitly our ISF coders, we developed a stochastic joint source-channel coding system based on a reduced complexity version of the channel optimized SSVQ technique. Simulation results will show that our new encoding system, called ISF-SCOSSVQ coder, can provide a good implicit protection to ISF parameters. The ISF-SCOSSVQ coder was further used to encode the ISF parameters of the Adaptive Multi-rate Wideband (AMR-WB, ITU-T G.722.2) speech coder operating over a noisy channel. We will show that the proposed ISF-SCOSSVQ coder contribute significantly in the improvement of the AMR-WB performance by ensuring a good coding robustness of its ISF parameters. (C) 2014 Elsevier B.V. All rights reserved.

关键词： SSVQ quantization source-channel coding Robust speech coding ISF parameters Wideband speech coder

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source fidelity over fading channels: Performance of erasure and scalable codes

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IEEE TRANSACTIONS ON COMMUNICATIONS 2008年第7期56卷 1080-1091页

作者： Zachariadis, Konstantinos E. Honig, Michael L. Katsaggelos, Aggelos K. NW Univ Kellogg Sch Management Evanston IL 60201 USA NW Univ Dept Elect Engn & Comp Sci Evanston IL 60208 USA

We consider the transmission of a Gaussian source through a block fading channel. Assuming each block is decoded independently, the received distortion depends on the trade-off between quantization accuracy and probability of outage. Namely higher quantization accuracy requires a higher. channel code rate, which increases the probability of outage. We first treat an outage as an erasure, and evaluate the received mean distortion with erasure coding across blocks as a function of the code length. We then evaluate the performance of scalable, or multi-resolution coding in which coded layers are superimposed within a coherence block, and-the layers are sequentially decoded. Both the rate and power allocated to each layer are optimized. In addition to analyzing the performance with a finite number of layers, we evaluate the mean distortion at high Signal-to-Noise Ratios as the number of layers becomes infinite. As the block length of the erasure code increases to infinity, the received distortion converges to a deterministic limit, which is less than the mean distortion with an infinite-layer scalable coding scheme. However, for the same standard deviation in received distortion, infinite layer scalable coding performs slightly better than erasure coding, and with much less decoding delay.

关键词： source-channel coding scalable coding fading channel broadcast channel rate distortion

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Power-Reductive Precoding for the Transmission of Correlated Information Sequences

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IEEE TRANSACTIONS ON COMMUNICATIONS 2013年第4期61卷 1393-1403页

作者： Tanahashi, Makoto Ochiai, Hideki Toshiha Res & Dev Ctr Kawasaki Kanagawa Japan Yokohama Natl Univ Dept Elect & Comp Engn Yokohama Kanagawa 2408501 Japan

In communication theory, the conventional role of precoding is to reshape a spectrally flat sequence of data symbols in favor of a particular inter-symbol interference (ISI) channel such that signal-to-noise power ratio (SNR) is maximized. In contrast, in this paper a novel precoding technique is devised to exploit a particular property of the information source rather than the channel. Specifically, we focus on the scenario where the source sequence has an inherent correlation that is known a priori, and design a precoding filter that attempts to reduce the average power of the resulting transmit symbol sequences. The proposed precoding technique is thus termed power-reductive precoding (PRP). This reduction of average transmit power accrues without changing the amplitude of the original sequence and thus can be treated as a system gain. An apparent drawback of this approach is the intentional ISI introduced by the precoding filter, which may lessen the minimum distance among legitimate sequences. Nevertheless, we show that even if the loss associated with the minimum distance penalty is properly taken into account, the achievable error rate versus SNR can be made superior to the case without precoding.

关键词： Correlated sources source-channel coding ISI channel precoding

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Optimal binary index assignments for a class of equiprobable scalar and vector quantizers

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IEEE TRANSACTIONS ON INFORMATION THEORY 1995年第6期41卷 2031-2037页

作者： McLaughlin, SW Neuhoff, DL Ashley, JJ UNIV MICHIGAN DEPT ELECT ENGN & COMP SCIANN ARBORMI 48109 IBM CORP ALMADEN RES CTRSAN JOSECA 95120

The problem of scalar and vector quantization in conjunction with a noisy binary symmetric channel is considered. The issue is the assignment of the shortest possible distinct binary sequences to quantization levels or vectors so as to minimize the mean-squared error caused by channel errors. By formulating the assignment as a matrix (or vector in the scalar case) and showing that the mean-squared error due to channel errors is determined by the projections of its columns onto the eigenspaces of the multidimensional channel transition matrix, a class of source/quantizer pairs Is identified for which the optimal index assignment has a simple and natural form. Among other things, this provides a simpler and more accessible proof of the result of Crimmins et al., that the natural binary code is an optimal index assignment for the uniform scalar quantizer and uniform source. It also provides a potentially useful approach to further developments in source-channel coding.

关键词： source-channel coding natural binary code vector quantization

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A Multiway Relay channel With Balanced sources

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IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第12期63卷 4809-4823页

作者： Ong, Lawrence Timo, Roy Univ Newcastle Sch Elect Engn & Comp Sci Callaghan NSW 2308 Australia Tech Univ Munich Inst Commun Engn D-80333 Munich Germany

We consider a joint source-channel coding problem on a finite-field multiway relay channel, and we give closed-form lower and upper bounds on the optimal source-channel rate. These bounds are shown to be tight for all discrete memoryless sources in a certain class P*, and we demonstrate that strict source-channel separation is optimal within this class. We show how to test whether a given source belongs to P*, we give a balanced-information regularity condition for P*, and we express P* in terms of conditional multiple-mutual information. Finally, we show that P* is useful for a centralized storage problem.

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Multistage vector quantizer optimization for packet networks

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2003年第7期51卷 1870-1879页

作者： Khalil, H Rose, K Univ Calif Santa Barbara Dept Elect & Comp Engn Santa Barbara CA 93106 USA

A multistage vector quantizer (MSVQ) based coding system is source-channel optimized for packet networks.,Resilience to packet loss is enhanced by a proposed interleaving approach that ensures that a single lost packet only eliminates a subset of the vector stages. The design is optimized while taking into account compression efficiency, packet loss rate, and the interleaving technique in use. The new source-channel-optimized MSVQ is tested on memoryless speech line spectral frequency (LSF) parameter quantization as well as block-based image compression. With LSF coding, a source-channel-optimized MSVQ is shown to yield gains of up to 2.0 dB in signal-to-ratio (SNR) over traditional MSVQ and to substantially enhance the robustness of packetized speech transmission. Substantial gains were also obtained in the case of block-based image compression. Although the formulation is given in the context of packet networks, the work is directly extendible to the broader category of erasure channels.

关键词： erasure channels multistage vector quantizer packet networks source-channel coding

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