The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Recent results on source-channel coding for secure transmission show that separation holds in several cases under some less-noisy conditions. However, it has also been proved through a simple counterexample that pure analog schemes can be optimal and hence outperform digital ones. According to these observations and assuming matched-bandwidth, we present a novel hybrid digital/analog scheme that aims...
We study a secure distributed source coding problem. Two terminals with correlated observations would like to send their observations securely to a receiver using minimal transmission rates and key rates. By providing a converse, we show the optimality of a natural structure, in which Slepian-Wolf distributed compression is followed by an application of a onetime pad for encryption. Hence, in contrast...
This paper considers the problem of characterizing the optimal tradeoff between the total transmit versus receive rate in the Gray-Wyner network. This tradeoff plays a crucial role in many important practical applications including establishing fundamental limits in databases for correlated sources and in minimum cost routing for networks. We develop the insight into this tradeoff by defining two...
We recently proposed a new coding scheme for the L-channel multiple descriptions (MD) problem for general sources and distortion measures involving ‘Combinatorial Message Sharing’ (CMS) [7] leading to a new achievable rate-distortion region. Our objective in this paper is to establish that this coding scheme strictly subsumes the most popular region for this problem due to Venkataramani, Kramer and...
We study a problem in which a source is encoded into n packets, any t of which may be altered in an arbitrary way by Byzantine adversaries. The decoder receives the n packets and, without knowing which packets were altered, seeks to reconstruct the original source to meet a distortion constraint. We examine a layered architecture for this problem that separates the lossy compression from the coding...
Polar codes, introduced by Arikan recently, can achieve capacity of symmetric channel with low complexity successive cancellation decoding strategy. In this paper, we design efficient Bhattacharyya Parameters in Polar codes construction for common communications channels. We present the satisfactory recursive formula for the four conventional channels and discuss the initial value of each recursive...
Distributed compression or Distributed Source Coding (DSC) refers to separate compression and joint decompression of multiple correlated sources. Though theoretical foundations were set almost forty years ago, driven by applications such as wireless video surveillance and wireless multimedia communications, DSC has become and still is a very active research area with interest from both academia and...
This work studies the error resilience of pixel-domain distributed video coding in noisy wireless transmission environment. Turbo codes are used to implement the DVC coder and the AWGN model is assumed for the transmission channel. The goal is to find out whether symbol based coding or bit-plane based coding is more robust against channel noise. We compare the two in the context of joint source-channel...
A distributed coding algorithm is presented for compression of wavelet-transformed data. Data structures based on zerotrees are exploited for efficient compression of the significance map of wavelet coefficients. The coefficients are scanned in two stages, with a significance pass and refinement pass, similar to the SPIHT algorithm. The bits resulting from these passes are Slepian-Wolf coded using...
The problem of transmitting a source across a parallel channel with random states only known at the decoder is considered. We focus on minimizing the average distortion. The general problem is unsolved. There are two commonly used architecture, namely source coding diversity and channel coding diversity, which exploit diversity through parallel channel coding or multiple description (MD) source coding...
We consider the problem of gathering measurements in a wireless sensor network consisting of a large number of sensor nodes. A practical joint source-channel coding scheme is proposed and evaluated. The scheme uses lattices to extend a previously proposed scheme to higher dimensions. The key idea is to use conventional point-to-point communication for a subset of the sensor nodes and side-information...
A new coding concept called credit-based variable-to-variable length (cbv2v) coding is proposed in this paper. A binary cbv2v code is constructed, and analysis of its performance shows that cbv2v coding can achieve much better trade-off among the coding delay, redundancy, and space complexity than does variable-to-variable length (v2v) coding. Specifically, let L be the total number of source words...
Quantizer design for lossy compression with mismatched side information (SI) at the decoder is investigated. The statistical dependency between the source and SI is assumed to be a function of a random variable, dependency variable (DV). According to the available information about the DV, three design methods are proposed; namely, minimax solution, Average Distribution and Multi-Mode Decoder. The...
Practical codes are developed for quadratic Gaussian lossy compression when side information may be absent by hybridizing successively refinable trellis coded quantization (SR-TCQ) and low-density parity-check (LDPC) codes. A 2-refinement level SR-TCQ is used to generate a common description for both decoders and an individual description for the decoder with side information. Then, the common description...
We study the scenario of pixel-domain distributed video coding for noisy transmission environments and propose a method to allocate the available rate between source coding and channel coding to generate a robust video stream. Having observed in experiments the uncertainty of the source and the channel coding rate, we model them as random variables via offline training, estimate the decoding failure...
Canonical distributed quantization schemes do not scale to large sensor networks due to the exponential decoder storage complexity that they entail. Prior efforts to tackle this issue have largely been limited to the suboptimal schemes of source grouping and decoding, thus failing to use all available information at the decoder. We propose a new decoding paradigm where all received bits are used in...
In this paper a new scheme is proposed for progressive image transmission over coded Orthogonal Frequency Division Multiplexing (OFDM) system with Low Density Parity Check Coding (LDPC). Trigonometric transforms are used in this scheme for improving the performance of the OFDM systems and reducing the Peak-to-Average Power Ratio (PAPR) of OFDM signal. It improves the error resilience ability and transmission...
In this paper we consider the rate region of the vector Gaussian one-helper distributed source coding problem. In particular, we derive optimality conditions under which a weighted sum rate is minimum by using a contradiction-based argument. When the sources are specified to be scalar, the optimality conditions can always be constructed for any weighted sum rate. In the derivation of the optimality...
In this paper, the authors propose a variable length source code that achieves very good performance even for short sequences and has low encoding complexity, although it does not achieve the theoretical limit. Furthermore, the performance can be predicted for infinite codeword length with close form expressions, and has been proven to be good even when a suboptimum decoder with very low complexity...
Multiple description coding (MDC) is one of source coding techniques which generate several descriptions from a single data. A decoder of MDC reconstructs the data from these descriptions. Even if some descriptions are lost, the decoder can reconstruct a similar data from the other descriptions. Therefore, this coding technique is expected to apply applications which prefer accepting error of data...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.