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The method of types is frequently used to analyze commu nication channels with arbitrary memory. It is therefore a useful tool to study communication problems with an adversary (who need not be limited by memory constraints). This paper presents an introduction to the method of types and reviews recent applications of the method to information hiding. These problems include capacity and error -exponent...
At the heart of data compression is the search for how information is organized in data. This search for organization can focus on the data itself, on the source of the information, or on the sink, or user of the information. Analogous approaches can be used to identify how information is organized in the DNA sequence. In this talk we describe how techniques which have proven useful in developing...
In this paper, we present an algebraic description of the aliasing phenomena evident in the linear sampling process of multidimensional periodic band limited signals. Opposed to the classical Shannon sampling, periodic band limited signals underlie a different aliasing structure providing further freedom in the sampling strategy due to the discreteness of the spectrum. An algebraic formulation of...
In this study, a new approach is presented for analysis of EEG signals and detection and localization of sleep spindles. For automatic detection of sleep spindles, short term frequency analysis is applied to EEG data. Short Time Fourier Transform, and Wavelet Transform are used extensively. After the detection of sleep spindles, Teager Operator is applied to determine the duration of the spindle....
Recently, the authors have proposed a novel approach to Direction-Of-Arrival (DOA) estimation using the ℋ∞ criterion. This article examines the limits of performance of ℋ∞-based direction finding and arrives at a lower bound on the estimation error, analogous to the Cramer-Rao Bound (CRB). Furthermore, the analysis of the ℋ∞-based algorithm's prediction error using one of Akaike's information criteria...
This document describes a haptic application that allows blind people recognize three-dimensional (3D) objects that exist in virtual environment. The system allows blind people to touch, grasp and manipulate objects that exist in the haptic enabled VE. The system is designed in order to provide an alternative way of human computer interaction to blind users.
In this paper, we present two versions of a demonstrator for gaze direction estimation. The first version is based on the analysis and the interpretation of head movements, especially in case of important head rotations. In such a case, we suppose that the gaze direction coincides with the head orientation. The second version of the demonstrator is based on the analysis of the iris centres positions...
Automatic real-time translation of gestured languages for hearing-impaired would be a major advance on disabled integration path. In this paper, we present a demonstrator on Cued Speech hand gesture recognition.
In this paper, we address the blind separation problem of binaural mixed signals, and propose a novel blind separation method using Single-Input-Multiple-Output-model-based independent component analysis (SIMO-ICA) with a self-generator (SG) for the initial filter. SIMO-ICA which has been proposed by the authors can separate mixed signals, not into monaural source signals but into SIMO-model-based...
In adaptive signal processing, joint process estimation plays an important role in various estimation problems. It is well known that a joint process estimator consists of two structures, namely the orthogonalizer and the regression filter. In literature, orthogonalization step is performed either by orthogonal transformations or by linear predictors. While the orthogonal transformations do not preserve...
In this paper, we present a dynamic programming approach to voice transformation (VT). The goal of VT is to modify the speech of a source speaker such that it is perceived as if spoken by a target speaker. The speech model used in this work is based on MELP (Mixed Excitation Linear Prediction) speech coding algorithm. The designed system obtains speaker-specific codebooks of line spectral frequencies...
Programmability with its associated flexibility will be increasingly important in future multi-standard radio systems. We are presenting a fully programmable and flexible DSP platform capable of efficiently performing channel estimation and MRC-based channel equalization for several CDMA based wireless transmission systems in software. Our processor is based on a DSP core with SIMD-computing clusters...
In multi-class problems, within- and between-class scatters should be considered in classification criterion. The common vector approach (CVA) uses the discriminative information obtained from within-class scatter of any class. It has been shown that this classical CVA method gives high recognition rates in multi-class problems. In this study, improvements on the CVA method that consider both within-...
Coset-based codes are often proposed as an alternative to the theoretical probabilistic random binning in network coding. In this paper nested lattice codes recently proposed for multiterminal binning are used to devise a structured high dimensional Costa scheme for data hiding. The resulting embedding scheme overcomes both the famous Scalar Costa Scheme (SCS) and regular Quantization Index Modulation...
A new iterative speech enhancement scheme that can be seen as an approximation to the Expectation-Maximization (EM) algorithm is proposed. The algorithm employs a Kalman filter that models the excitation source as a spectrally white process with a rapidly time-varying variance, which calls for a high temporal resolution estimation of this variance. A Local Variance Estimator based on a Prediction...
In this paper, the pulse shape design for various communication systems including PAM, FSK, and PSK is considered. The pulse is designed by imposing constraints on the time and frequency domains constraints on the autocorrelation function of the pulse shape. Intersymbol interference, finite duration and spectral mask restrictions are a few examples leading to convex sets in L2. The autocorrelation...
We consider cyclically prefixed block transmission over frequency selective wireless multiple input multiple output (MIMO) channels. We make a bit rate comparison between MIMO cyclically prefixed single carrier (CP-SC) and MIMO orthogonal frequency division multiplexing (OFDM) systems. We analytically prove that MIMO CP-SC with decision feedback equalization (DFE) outperforms MIMO OFDM with linear...
The goal of partial encryption of a bit stream is to make the entire stream somehow useless for anyone that cannot decrypt its ciphered subset. In this paper we present the effects of the partial encryption of some H.264/AVC coding parameters, in order to obtain a moderate degradation of the video content, which can be appealing for commercial applications, like pay-per-view systems and others, without...
In this paper a new class of filters designed for the removal of impulsive noise in color images is presented. The proposed filter class is based on the nonparametric estimation of the density probability function of pixels in a sliding filtering window. The comparison of the new filtering method with the standard techniques used for impulsive noise removal, indicates good noise removal capabilities...
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