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variable-length coding for performance improvement of asymptotically optimal unrestricted polar quantization of bivariate Gaussian source

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INFORMATION SCIENCES 2013年 252卷 157-167页

作者： Peric, Zoran Nikolic, Jelena Milic, Dejan Univ Nis Fac Elect Engn Nish Serbia

This paper considers the application of variable-length coding using two unrestricted polar quantizers (UPQs). for performance improvement of unrestricted polar quantization for bivariate Gaussian source. We propose the use of two UPQs, both designed for the bivariate Gaussian source of unit variance, having different sizes of codebooks and different optimal compressor functions. We show that the fixed-rate UPQ is a subset of our model, and we perform rigorous optimization procedure in order to obtain optimal parameter values maximizing the signal to quantization noise ratio (SQNR) for the given average bit rate. In addition, we study how gain in SQNR over the fixed-rate UPQ depends on the average bit rate and we show that the gain ranges from 0.619 dB to 0.869 dB depending on the average bit rate. Discussion is also provided about the proposed quantizer complexity and its performance in comparison to Shannon limit. The proposed UPQ provides a sophisticated choice of average bit rate compared to the fixed-rate UPQ. Features of the proposed quantizer indicate that the obtained model should be of high theoretical and practical significance. (c) 2013 Elsevier Inc. All rights reserved.

关键词： Bivariate Gaussian source Optimal compressor function Unrestricted polar quantization variable-length coding

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variable-length coding of Two-sided Asymptotically Mean Stationary Measures

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JOURNAL OF THEORETICAL PROBABILITY 2010年第1期23卷 237-256页

作者： Debowski, Lukasz Ctr Wiskunde & Informat NL-1098 XG Amsterdam Netherlands

We collect several observations that concern variable-length coding of two-sided infinite sequences in a probabilistic setting. Attention is paid to images and preimages of asymptotically mean stationary measures defined on subsets of these sequences. We point out sufficient conditions under which the variable-length coding and its inverse preserve asymptotic mean stationarity. Moreover, conditions for preservation of shift-invariant sigma-fields and the finite-energy property are discussed, and the block entropies for stationary means of coded processes are related in some cases. Subsequently, we apply certain of these results to construct a stationary nonergodic process with a desired linguistic interpretation.

关键词： Asymptotically mean stationary processes variable-length coding Synchronization Shift-invariant algebras Complete fix-free sets Finite-energy processes Block entropy

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variable-length coding With Shared Incremental Redundancy: Design Methods and Examples

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IEEE TRANSACTIONS ON COMMUNICATIONS 2019年第9期67卷 5981-5995页

作者： Wang, Haobo Ranganathan, Sudarsan V. S. Wesel, Richard D. SK Hynix Memory Solut Amer Inc San Jose CA 95134 USA MIT IDSS Cambridge MA 02142 USA Univ Calif Los Angeles Dept Elect & Comp Engn Los Angeles CA 90095 USA

variable-length (VL) coding with feedback is a commonly used technique that can approach point-to-point Shannon channel capacity with a significantly shorter average codeword length than fixed-length coding without feedback. This paper uses the inter-frame coding of Zeineddine and Mansour, originally introduced to address varying channel-state conditions in broadcast wireless communication, to approach capacity on point-to-point channels using VL codes without feedback. The per-symbol complexity is comparable to decoding the VL code with feedback (plus the additional complexity of a small peeling decoder amortized over many VL codes) and presents the opportunity for encoders and decoders that utilize massive parallel processing, where each VL decoder can process simultaneously. This paper provides an analytical framework and a design process for the degree distribution of the inter-frame code that allows the feedback-free system to achieve 96% or more of the throughput of the original VL code with feedback. As examples of VL codes, we consider non-binary (NB) low-density parity-check (LDPC), binary LDPC, and convolutional VL codes. The NB-LDPC VL code with an 8-bit CRC and an average codeword length of 336 bits achieves 85% of capacity with four rounds of ACK/NACK feedback. The proposed scheme using shared incremental redundancy without feedback achieves 97% of that performance or 83% of the channel capacity.

关键词： Forward error correction incremental redundancy feedback channel capacity broadcast point-to-point low density parity check codes non-binary low density parity check codes convolutional codes variable-length coding hybrid ARQ

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Test data compression scheme based on variable-to-fixed-plus-variable-length coding

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JOURNAL OF SYSTEMS ARCHITECTURE 2007年第11期53卷 877-887页

作者： Zhan, Wenfa Liang, Huaguo Shi, Feng Huang, Zhengfeng Hefei Univ Technol Sch Comp & Informat Hefei Anhui Peoples R China

A test data compression scheme based on variable-to-Fixed-Plus-variable-length (VTFPVL) coding is presented, by using which the test data can be compressed efficiently. In this scheme, code words are divided into fixed-length head section and variable-length tail section. In order to attain further compression, the highest bit of the tail is omitted from the code words, because all of the highest bits in the tail section of the code words are the same as 1. A special shift counter is also used, which further eases the control circuit. Experimental results of the MinTest fault sets which are part of ISCAS-89 benchmark circuits show that the proposed scheme is obviously better than traditional coding methods in the compression ratio and the implementation of decompression, such as Golomb, FDR, VIHC, v9C coding. (c) 2007 Elsevier B.V. All rights reserved.

关键词： test data compression coding fixed-length coding variable-length coding

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Extrinsic Jensen-Shannon Divergence: Applications to variable-length coding

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IEEE TRANSACTIONS ON INFORMATION THEORY 2015年第4期61卷 2148-2164页

作者： Naghshvar, Mohammad Javidi, Tara Wigger, Michele Univ Calif San Diego Dept Elect & Comp Engn San Diego CA 92093 USA Univ Calif San Diego Dept Elect & Comp Engn La Jolla CA 92093 USA Telecom ParisTech Dept Commun & Elect F-75013 Paris France

This paper considers the problem of variable-length coding over a discrete memoryless channel with noiseless feedback. This paper provides a stochastic control view of the problem whose solution is analyzed via a newly proposed symmetrized divergence, termed extrinsic Jensen-Shannon (EJS) divergence. It is shown that strictly positive lower bounds on EJS divergence provide nonasymptotic upper bounds on the expected code length. This paper presents strictly positive lower bounds on EJS divergence, and hence nonasymptotic upper bounds on the expected code length, for the following two coding schemes: 1) variable-length posterior matching and 2) MaxEJS coding scheme that is based on a greedy maximization of the EJS divergence. As an asymptotic corollary of the main results, this paper also provides a rate-reliability test. variable-length coding schemes that satisfy the condition(s) of the test for parameters R and E are guaranteed to achieve a rate R and an error exponent E. The results are specialized for posterior matching and MaxEJS to obtain deterministic one-phase coding schemes achieving capacity and optimal error exponent. For the special case of symmetric binary-input channels, simpler deterministic schemes of optimal performance are proposed and analyzed.

关键词： Discrete memoryless channel variable-length coding sequential analysis feedback gain Burnashev's reliability function optimal error exponent

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Distributed Hypothesis Testing With variable-length coding

IEEE JOURNAL ON SELECTED AREAS IN INFORMATION THEORY

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IEEE JOURNAL ON SELECTED AREAS IN INFORMATION THEORY 2020年第3期1卷 681-694页

作者： Salehkalaibar, Sadaf Wigger, Michele Univ Tehran Dept Elect & Comp Engn Coll Engn Tehran *** Iran Telecom Paris LTCI F-91120 Paris France

The problem of distributed testing against independence with variable-length coding is considered when the average and not the maximum communication load is constrained as in previous works. The paper characterizes the optimum type-II error exponent of a single-sensor single-decision center system given a maximum type-I error probability when communication is either over a noise-free rate-R link or over a noisy discrete memoryless channel (DMC) with stop-feedback. Specifically, let epsilon denote the maximum allowed type-I error probability. Then the optimum exponent of the system with a rate-R link under a constraint on the average communication load coincides with the optimum exponent of such a system with a rate R/(1 - epsilon) link under a maximum communication load constraint. A strong converse thus does not hold under an average communication load constraint. A similar observation also holds for testing against independence over DMCs. With variable-length coding and stop-feedback and under an average communication load constraint, the optimum type-II error exponent over a DMC of capacity C equals the optimum exponent under fixed-length coding and a maximum communication load constraint when communication is over a DMC of capacity C/(1 - epsilon).

关键词： variable-length coding distributed hypothesis testing discrete memoryless channels strong converse

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Cooperative Multi-Sensor Detection under variable-length coding

Cooperative Multi-Sensor Detection under Variable-Length Cod...

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IEEE Information Theory Workshop (ITW)

作者： Hamad, Mustapha Wigger, Michele Sarkiss, Mireille Telecom Paris IP Paris LTCI F-91120 Palaiseau France Telecom SudParis IP Paris SAMOVAR F-91011 Evry France

ISBN: (纸本)9781728159621

We investigate the testing-against-independence problem over a cooperative MAC with two sensors and a single detector under an average rate constraint on the sensors-detector links. For this setup, we design a variable-length coding scheme that maximizes the achievable type-II error exponent when the type-I error probability is limited to epsilon. Similarly to the single-link result, we show here that the optimal error exponent depends on epsilon and that variable-length coding allows to increase the rates over the optimal fixed-length coding scheme by the factor (1 - epsilon)(-1).

关键词： Distributed Hypothesis Testing Cooperative MAC variable-length coding Error Exponent

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A variable-length coding adjustable for compressed test application

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2007年第8期E90D卷 1235-1242页

作者： Ichihara, Hideyuki Ohara, Toshihiro Shintani, Michihiro Inoue, Tomoo Hiroshima City Univ Hiroshima 7313194 Japan

Test compression / decompression using variable-length coding is an efficient method for reducing the test application cost, i.e., test application time and the size of the storage of an LSI tester. However, some coding techniques impose slow test application, and consequently a large test application time is required despite the high compression. In this paper, we clarify the fact that test application time depends on the compression ratio and the length of codewords and then propose a new Huffman-based coding method for achieving small test application time in a given test environment. The proposed coding method adjusts both of the compression ratio and the minimum length of the codewords to the test environment. Experimental results show that the proposed method can achieve small test application time while keeping high compression ratio.

关键词： test compression variable-length coding test application time ATE Huffman code test environment

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variable length coding over an unknown channel

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IEEE TRANSACTIONS ON INFORMATION THEORY 2006年第5期52卷 2126-2145页

作者： Tchamkerten, A Telatar, IE MIT Dept Elect Engn & Comp Sci Cambridge MA 02139 USA Ecole Polytech Fed Lausanne Informat Theory Lab LTHI ISC I&C CH-1015 Lausanne Switzerland

Burnashev in 1976 gave an exact expression for the reliability function of a discrete memoryless channel (DMC) with noiseless feedback. A coding scheme that achieves this exponent needs, in general, to know the statistics of the channel. Suppose now that the coding scheme is designed knowing only that the channel belongs to a family Q of DMCs. Is there a coding scheme with noiseless feedback that achieves Burnashev's exponent uniformly over Q at a nontrivial rate? We answer the question in the affirmative for two families of channels (binary symmetric, and Z). For these families we show that, for any given fraction, there is a feedback coding strategy such that for any member of the family: i) guarantees this fraction of its capacity as rate, and ii) guarantees the corresponding Burnashev's exponent. Therefore, for these families, in terms of delay and error probability, the knowledge of the channel becomes asymptotically irrelevant in feedback code design: there are blind schemes that perform as well as the best coding scheme designed with the foreknowledge of the channel under use. However, a converse result shows that, in general, even for families that consist of only two channels, such blind schemes do not exist.

关键词： Burnashev's exponent error exponent feedback universal channel coding variable-length coding

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Reversible Data Hiding With Hierarchical Block variable length coding for Cloud Security

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IEEE TRANSACTIONS ON DEPENDABLE AND SECURE COMPUTING 2023年第5期20卷 4199-4213页

作者： Xu, Shuying Horng, Ji-Hwei Chang, Ching-Chun Chang, Chin-Chen Feng Chia Univ Dept Informat Engn & Comp Sci Taichung 407102 Taiwan Natl Quemoy Univ Dept Elect Engn Kinmen 892 Taiwan Univ Warwick Comp Sci Coventry CV4 7AL W Midlands England

Reversible data hiding in encrypted images (RDHEI) can serve as a technical solution to secure data in applications that rely on cloud storage. The key features of an RDHEI scheme are reversibility, security, and data embedding rate. To enlarge the embedding rate, this paper proposes a novel RDHEI scheme based on the median edge detector (MED) and a new proposed hierarchical block variable length coding (HBVLC) technique. In our scheme, the image owner first predicts the pixel values of the carrier image with MED. Then, the prediction error array is sliced into bit-planes and encoded plane by plane. By leveraging the inherent features of the prediction error bit-planes, the image owner adaptively decomposes a bit-plane into blocks of different hierarchical levels based on its local smoothness and encodes the blocks with a variable length coding method. As a result, the carrier image is efficiently compressed to provide spare room for data embedding. The encoded carrier image is then processed with the conventional steps of an RDHEI technique. Experimental results show that the proposed scheme not only can restore the secret data and the carrier image without loss but also outperforms state-of-the-art methods in the embedding rate for images with various features.

关键词： Cryptography Image coding Encryption Medical diagnostic imaging Encoding Medical services Streaming media Image encryption Median-edge detector Reversible data hiding variable-length coding

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