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218
Multiple Description Coding with Many Channels
 IEEE TRANS. INFORM. THEORY
, 2003
"... An achievable region for thechannel multiple description coding problem is presented. This region generalizes twochannel results of El Gamal and Cover and of Zhang and Berger. It further generalizes threechannel results of Gray and Wyner and of Zhang and Berger. A source that is successively refi ..."
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Cited by 74 (1 self)
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An achievable region for thechannel multiple description coding problem is presented. This region generalizes twochannel results of El Gamal and Cover and of Zhang and Berger. It further generalizes threechannel results of Gray and Wyner and of Zhang and Berger. A source that is successively refinable on chains is shown to be successively refinable on trees. A new outer bound on the ratedistortion (RD) region for memoryless Gaussian sources with mean squared error distortion is also derived. The achievable region meets this outer bound for certain symmetric cases.
nchannel symmetric multiple descriptions–part I: (n, k) sourcechannel erasure codes
 IEEE Trans. Inform. Theory
, 2004
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A Comparison of Layering and Stream Replication Video Multicast Schemes
, 2001
"... The heterogeneity of the Internet's transmission resources and end system capability makes it difficult to agree on acceptable traffic characteristics among the multiple receivers of a multicast video stream. Three basic approaches have been proposed to deal with this problem: 1) multicasting o ..."
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Cited by 60 (2 self)
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The heterogeneity of the Internet's transmission resources and end system capability makes it difficult to agree on acceptable traffic characteristics among the multiple receivers of a multicast video stream. Three basic approaches have been proposed to deal with this problem: 1) multicasting of replicated video streams at different rates, 2) multicasting the video encoded in cumulative layers, and 3) multicasting the video encoded in noncumulative layers. Even though there is a common belief that the layering approach is better than the replicated stream approach, there has been no studies that compare these schemes. This paper is devoted to such a systematic comparison. Our starting point is an observation (substantiated by results in the literature) that a bandwidth penalty is incurred by encoding a video stream in layers. We argue that a fair comparison of these schemes needs to take into account this penalty as well as the specifics of the encoding used in each scheme, protocol complexity, and the topological placement of the video source and the receivers relative to each other. Our results show that the believed superiority of layered multicast transmission relative to stream replication is not as clear cut as is widely believed and that there are indeed scenarios where replication is the preferred approach.
Image coding based on a morphological representation of wavelet data
 IEEE TRANSACTIONS ON IMAGE PROCESSING
, 1999
"... In this paper, an experimental study of the statistical properties of wavelet coefficients of image data is presented, as well as the design of two different morphologybased image coding algorithms that make use of these statistics. A salient feature of the proposed methods is that, by a simple ch ..."
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Cited by 52 (7 self)
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In this paper, an experimental study of the statistical properties of wavelet coefficients of image data is presented, as well as the design of two different morphologybased image coding algorithms that make use of these statistics. A salient feature of the proposed methods is that, by a simple change of quantizers, the same basic algorithm yields high performance embedded or fixed rate coders. Another important feature is that the shape information of morphological sets used in this coder is encoded implicitly by the values of wavelet coefficients, thus avoiding the use of explicit and rate expensive shape descriptors. These proposed algorithms, while achieving nearly the same objective performance of stateoftheart zerotree based methods, are able to produce reconstructions of a somewhat superior perceptual quality, due to a property of joint compression and noise reduction they exhibit.
Fifty Years of Shannon Theory
, 1998
"... A brief chronicle is given of the historical development of the central problems in the theory of fundamental limits of data compression and reliable communication. ..."
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Cited by 50 (1 self)
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A brief chronicle is given of the historical development of the central problems in the theory of fundamental limits of data compression and reliable communication.
Sourcechannel diversity for parallel channels
 IEEE TRANSACTIONS ON INFORMATION THEORY
, 2005
"... We consider transmitting a source across a pair of independent, nonergodic channels with random states (e.g., slowfading channels) so as to minimize the average distortion. The general problem is unsolved. Hence, we focus on comparing two commonly used source and channel encoding systems which corr ..."
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Cited by 49 (5 self)
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We consider transmitting a source across a pair of independent, nonergodic channels with random states (e.g., slowfading channels) so as to minimize the average distortion. The general problem is unsolved. Hence, we focus on comparing two commonly used source and channel encoding systems which correspond to exploiting diversity either at the physical layer through parallel channel coding or at the application layer through multiple description (MD) source coding. For on–off channel models, source coding diversity offers better performance. For channels with a continuous range of reception quality, we show the reverse is true. Specifically, we introduce a new figure of merit called the distortion exponent which measures how fast the average distortion decays with signaltonoise ratio. For continuousstate models such as additive white Gaussian noise (AWGN) channels with multiplicative Rayleigh fading, optimal channel coding diversity at the physical layer is more efficient than source coding diversity at the application layer in that the former achieves a better distortion exponent. Finally, we consider a third decoding architecture: MD encoding with joint source–channel decoding. We show that this architecture achieves the same distortion exponent as systems with optimal channel coding diversity for continuousstate channels, and maintains the advantages of MD systems for on–off channels. Thus, the MD system with joint decoding achieves the best performance from among the three architectures considered, on both continuousstate and on–off channels.
Multiresolution vector quantization
 IEEE TRANS. INF. THEORY
, 2004
"... Multiresolution source codes are data compression algorithms yielding embedded source descriptions. The decoder of a multiresolution code can build a source reproduction by decoding the embedded bit stream in part or in whole. All decoding procedures start at the beginning of the binary source descr ..."
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Cited by 45 (4 self)
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Multiresolution source codes are data compression algorithms yielding embedded source descriptions. The decoder of a multiresolution code can build a source reproduction by decoding the embedded bit stream in part or in whole. All decoding procedures start at the beginning of the binary source description and decode some fraction of that string. Decoding a small portion of the binary string gives a lowresolution reproduction; decoding more yields a higher resolution reproduction; and so on. Multiresolution vector quantizers are block multiresolution source codes. This paper introduces algorithms for designing fixed and variablerate multiresolution vector quantizers. Experiments on synthetic data demonstrate performance close to the theoretical performance limit. Experiments on natural images demonstrate performance improvements of up to 8 dB over treestructured vector quantizers. Some of the lessons learned through multiresolution vector quantizer design lend insight into the design of more sophisticated multiresolution codes.
Capacity of a class of modulosum relay channels
 IEEE Trans. Inf. Theory
, 2009
"... Abstract—This paper characterizes the capacity of a class of modulo additive noise relay channels, in which the relay observes a corrupted version of the noise and has a separate channel to the destination. The capacity is shown to be strictly below the cutset bound in general and achievable using ..."
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Cited by 44 (3 self)
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Abstract—This paper characterizes the capacity of a class of modulo additive noise relay channels, in which the relay observes a corrupted version of the noise and has a separate channel to the destination. The capacity is shown to be strictly below the cutset bound in general and achievable using a quantizeandforward strategy at the relay. This result confirms a conjecture by Ahlswede and Han about the capacity of channels with rate limited state information at the destination for this particular class of channels. I.
Analog errorcorrecting codes based on chaotic dynamical systems.
 IEEE Trans. Communications,
, 1998
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Asymptotic Analysis of Multiple Description Quantizers
 IEEE Trans. Inform. Theory
, 1998
"... A high rate analysis is presented for multiple description quantizers introduced in [1], for rth power distortions and general source densities. Both, fixed length and variable length encoding of the quantizer indices are considered. Optimal companding functions are shown to be the same as for singl ..."
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Cited by 39 (5 self)
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A high rate analysis is presented for multiple description quantizers introduced in [1], for rth power distortions and general source densities. Both, fixed length and variable length encoding of the quantizer indices are considered. Optimal companding functions are shown to be the same as for single channel quantizers. As compared to the bound in [2], a gap of 8.69 dB and 3.07 dB exists between the entropyconstrained and levelconstrained cases, respectively, for a memoryless Gaussian source and r = 2, Index terms: Source Coding, Quantization, Data Compression, Multiple Descriptions, Diversity Systems. This work was was presented in part at the 1994 IEEE International Symposium on Information Theory, Trondheim, Norway, and was supported by grants NSF NCR9104566 and NSF NCR9314221. This work was performed while the first author was at Texas A&M University. 1 I Introduction We present an asymptotic analysis of multiple description scalar quantizers (MDSQ's), introduced in [1] fo...