This paper considers the problem of source coding with feedforward, where an encoder compresses an i.i.d. source into a message, and the decoder takes this message, along with causal noiseless side information, to con...
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This paper considers the problem of source coding with feedforward, where an encoder compresses an i.i.d. source into a message, and the decoder takes this message, along with causal noiseless side information, to construct an estimate of the source. The posterior matching scheme is an optimal feedback communication scheme for memoryless channels that results in the channel outputs being i.i.d. The duality between channel coding with feedback and source coding with feedforward motivates the idea of dualizing posterior matching for this setting. We demonstrate, using a Lyapunov exponent approach, that such a scheme attains the rate-distortion function.
We determine the rate region of a source coding problem with common reconstruction and action-dependent side information where an action sequence is taken by an encoder over a rate-limited link. We show that the rate ...
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We determine the rate region of a source coding problem with common reconstruction and action-dependent side information where an action sequence is taken by an encoder over a rate-limited link. We show that the rate region depends only on the sum-rate and the sum-rate distortion and cost function is characterized. The result serves as a fundamental limit in transmission scenarios where the encoder wants to control and monitor the quality of the decoder's reconstruction via the respective uses of action sequences and a common reconstruction constraint.
We consider a source coding scheme in which we use a mapping f /spl isin/ /spl Fscr/ as an encoder, where /spl Fscr/ is a class of universal hash functions. It is shown that, if /spl Fscr/ satisfies a certain conditio...
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We consider a source coding scheme in which we use a mapping f /spl isin/ /spl Fscr/ as an encoder, where /spl Fscr/ is a class of universal hash functions. It is shown that, if /spl Fscr/ satisfies a certain condition, for any discrete source there exist an encoder using an f /spl isin/ /spl Fscr/ and a decoder such that the decoding error probability becomes negligible for sufficiently large blocklength. We also give the error exponent of the minimum-entropy decoder for i.i.d. sources that is not less than the error exponent of linear encoders.
A key area of multimedia systems is source coding. We review the state of the art in source coding of speech, audio, image, and video signals, including discussions of both standards-based and nonstandard approaches t...
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A key area of multimedia systems is source coding. We review the state of the art in source coding of speech, audio, image, and video signals, including discussions of both standards-based and nonstandard approaches to coding. We demonstrate, via example, the current compression and coding capabilities of a wide range of algorithms, at various bit rates; for source coding of each of these signals. We also review the unique and challenging issues that face source coding on both wireless and data networks, and discuss the solutions that are currently being investigated.
We consider the problem of source coding with side information (SI) at the decoder only, when the joint distribution between the source and the SI is not perfectly known. Four parametric models for this joint distribu...
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We consider the problem of source coding with side information (SI) at the decoder only, when the joint distribution between the source and the SI is not perfectly known. Four parametric models for this joint distribution are considered, where uncertainty about the distribution is turned into uncertainty about the value of the parameters. More precisely, a prior distribution for the parameters may or may not be available. Moreover, the value of the parameters may either change at every symbol or remain constant for a while. This paper overviews the results on the performance of lossless source coding with SI at the decoder for the four models. The way LDPC-based encoding and decoding schemes should be designed to cope with model uncertainty is provided. Most of the proposed practical schemes perform close to the theoretical limits.
We consider the following rate distortion problem: given a source X and correlated, decoder side information Y, find the minimum encoding rate for X required to compute f(X,Y) at the decoder within distortion D. This ...
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ISBN:
(纸本)9781424413973;1424413974
We consider the following rate distortion problem: given a source X and correlated, decoder side information Y, find the minimum encoding rate for X required to compute f(X,Y) at the decoder within distortion D. This is a generalization of the classical Wyner-Ziv setup and was resolved by Yamamoto (1982). However, this result involved an auxiliary random variable that lacks explicit meaning. To provide a more direct link between this variable and the function f, Orlitsky and Roche (2001) established the minimal rate required in the zero-distortion case as an extension of Korner's graph entropy. Recently, we (with Jaggi) showed that the zero-distortion rate can be achieved by minimum entropy graph coloring of an appropriate product graph. This leads to a modular architecture for functional source coding with a preprocessing "functional coding" scheme operating on top of a classical Slepian-Wolf source coding scheme. In this paper, we give a characterization of Yamamoto's rate distortion function in terms of a reconstruction function. This (non-single-letter) characterization is an extension of our previous results as well as Orlitsky and Roche's results. We obtain a modular scheme operating with Slepian-Wolf's scheme for the problem of functional rate distortion. Further, we give an achievable rate (with single-letter characterization) utilizing this scheme that intuitively extends our previous results.
Practical schemes for distributed video coding with side information at the decoder need to consider non-standard correlation models in order to take non-stationarities into account. In this paper we introduce two cor...
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Practical schemes for distributed video coding with side information at the decoder need to consider non-standard correlation models in order to take non-stationarities into account. In this paper we introduce two correlation models for Gaussian sources, the Gaussian- Bernoulli-Gaussian (GBG) and the Gaussian-Erasure (GE) models, and evaluate lower and upper bounds on their rate-distortion functions. Provided that the probability of impulse noise or of erasures remains small, these bounds remain close to the rate-distortion function for Gaussian correlation. Two practical schemes for the GE correlation model are also presented, with performance about 1.5 dB away from the lower bound.
The continuous growth of traffic in the telecommunication networks has motivated the search for optimal source codes that can achieve high percentages of compression of the information to be transmitted. However, the ...
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ISBN:
(数字)9781728193656
ISBN:
(纸本)9781728193663
The continuous growth of traffic in the telecommunication networks has motivated the search for optimal source codes that can achieve high percentages of compression of the information to be transmitted. However, the compression rates are limited in the practice for the type of messages to encode. For this reason, new techniques have been developed in order to improve the compression rates of the traditional algorithms. In particular, source coding techniques based on computational intelligence algorithms are being studied lately. Hence, this paper proposes a new source coding technique for text compression based on two stages: the initial stage uses a deep neural network, called Text Embedding Neural Network, and the second stage uses a Canonical Huffman Code. The deep neural network increases the compression rate by controlling the level of syntax loss allowed in each message through a single adjustable parameter. This combination is able to reduce the size of the transmitted messages up to 30% with relation to only use traditional source coding algorithms.
The author considers an extended Slepian-Wolf system which has two decoders although the original Slepian-Wolf System has only one decoder. It is assumed that source outputs are i.i.d. but they are mutually correlated...
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The author considers an extended Slepian-Wolf system which has two decoders although the original Slepian-Wolf System has only one decoder. It is assumed that source outputs are i.i.d. but they are mutually correlated and the decoders communicate with each other via rate-restricted noiseless channels. Using the coding theorem derived the transmission rates of the decoders are examined.
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