Now showing items 291-310 of 508

    • New Dimensions In Wavelet Analysis 

      Baraniuk, Richard G.; Jones, Douglas L. (1992-03-01)
      In this paper we propose a new class of signal analysis tools that generalizes the popular wavelet and short-time Fourier transforms. The class allows skews and rotations of the analyzing wavelet in the time-frequency ...
    • A New Framework for Complex Wavelet Transforms 

      Fernandes, Felix; van Spaendonck, Rutger; Burrus, C. Sidney (2003-06-20)
      Although the Discrete Wavelet Transform (DWT) is a powerful tool for signal and image processing, it has three serious disadvantages: shift sensitivity, poor directionality and lack of phase information. To overcome these ...
    • A new look at the informational gain of soft decisions 

      Lexa, Michael; Johnson, Don (2003-04-20)
      This paper develops a new systematic method of studying the benefits of 2-bit soft decisions by applying the concepts of information processing theory. We quantify performance in terms of the information transfer ratio and ...
    • New multivariate dependence measures and applications to neural ensembles 

      Goodman, Ilan; Johnson, Don (2003-09-20)
      We develop two new multivariate statistical dependence measures. The first, based on the Kullback-Leibler distance, results in a single value that indicates the general level of dependence among the random variables. The ...
    • New Signal-Space Orthonormal Bases via the Metaplectic Transform 

      Baraniuk, Richard G.; Jones, Douglas L. (1992-10-01)
      The discretization of the metaplectic transform (MT) is considered, and it is shown that it can lead to completely new orthonormal bases (ONBs) for the signal space of square integrable functions. Two new classes of bases, ...
    • Noise Reduction Using an Undecimated Discrete Wavelet Transform 

      Lang, Markus; Guo, Haitao; Odegard, Jan E.; Burrus, C. Sidney; Wells, R.O. (1995-01-15)
      A new nonlinear noise reduction method is presented that uses the discrete wavelet transform. Similar to Donoho and Johnstone, we employ thresholding in the wavelet transform domain but, following a suggestion by Coifman, ...
    • Non-Redundant, Linear-Phase, Semi-Orthogonal, Directional Complex Wavelets 

      Fernandes, Felix; Wakin, Michael; Baraniuk, Richard G. (2004-05-01)
      The directionality and phase information provided by non-redundant complex wavelet transforms (NCWTs) provide significant potential benefits for image/video processing and compression applications. However, because existing ...
    • Nonlinear phase FIR filter design with minimum LS error and additional constraints 

      Lang, Markus; Bamberger, Joachim (1994-07-01)
      We examine the problem of approximating a complex frequency response by a real-valued FIR filter according to the <i>L<sub>2</sub></i> norm subject to additional inequality constraints for the complex error function. ...
    • Nonlinear Processing of a Shift Invariant DWT for Noise Reduction 

      Lang, Markus; Guo, Haitao; Odegard, Jan E.; Burrus, C. Sidney; Wells, R.O. (1995-04-20)
      A novel approach for noise reduction is presented. Similar to Donoho, we employ thresholding in some wavelet transform domain but use a nondecimated and consequently redundant wavelet transform instead of the usual orthogonal ...
    • Nonlinear Processing of a Shift Invariant DWT for Noise Reduction 

      Lang, Markus; Guo, Haitao; Odegard, Jan E.; Burrus, C. Sidney; Wells, R.O. (1995-03-20)
      A novel approach for noise reduction is presented. Similar to Donoho, we employ thresholding in some wavelet transform domain but use a nondecimated and consequently redundant wavelet transform instead of the usual orthogonal ...
    • Nonlinear Wavelet Processing for Enhancement of Images 

      Odegard, Jan E.; Lang, Markus; Guo, Haitao; Gopinath, Ramesh A.; Burrus, C. Sidney (1994-05-20)
      In this note we apply some recent results on nonlinear wavelet analysis to image processing. In particular we illustrate how the (soft) thresholding algorithm due to Donoho and Johnstone can successfully be used to remove ...
    • Nonlinear Wavelet Transforms for Image Coding 

      Claypoole, Roger L.; Davis, Geoffrey; Sweldens, Wim; Baraniuk, Richard G. (1997-11-01)
      We examine the central issues of invertibility, stability, artifacts, and frequency-domain characteristics in the construction of nonlinear analogs of the wavelet transform. The lifting framework for wavelet construction ...
    • Nonlinear Wavelet Transforms for Image Coding via Lifting 

      Claypoole, Roger L.; Davis, Geoffrey; Sweldens, Wim; Baraniuk, Richard G. (2003-12-01)
      We investigate central issues such as invertibility, stability, synchronization, and frequency characteristics for nonlinear wavelet transforms built using the lifting framework. The nonlinearity comes from adaptively ...
    • Nonlinear Wigner-Ville Spectrum Estimation using Wavelet Soft Thresholding 

      Baraniuk, Richard G. (1995-04-01)
      The large variance of the Wigner-Ville distribution makes smoothing essential for producing readable estimates of the time-varying power spectrum of noise corrupted signals. Since linear smoothing trades reduced variance ...
    • Nonlinear-Phase Maximally-Flat FIR Filter Deisgn 

      Selesnick, Ivan W.; Burrus, C. Sidney (1996-09-20)
      This paper reports a new analytic technique for the design of nonlinear-phase maximally-flat lowpass FIR filters. By subjecting the response magnitude and the group delay (individually) to differing numbers of flatness ...
    • Nonparametric, Low Bias, and Low Variance Time-Frequency Analysis of Myoelectric Signals 

      Farry, Kristin A; Baraniuk, Richard G.; Walker, Ian D (1995-09-01)
      The authors apply Thomson's multiple window method (see D. Thomson â Spectrum Estimation and Harmonic Analysisâ , Proc. of the IEEE, vol. 70, no. 9, p. 1055-96) to myoelectric signal time-frequency analysis for the first ...
    • Nonstationary signal classification using pseudo power signatures 

      Venkatachalam, Vidya; Aravena, Jorge.L. (1998-06-20)
      This paper deals with the problem of classification of nonstationary signals using signatures which are essentially independent of the signal length. We develop the notion of a separable approximation to the Continuous ...
    • Nonstationary signal classification using pseudo power signatures: The Matrix SVD Approach 

      Aravena, Jorge.L.; Venkatachalam, Vidya (1999-12-20)
      This paper deals with the problem of classification of nonstationary signals using signatures which are essentially independent of the signal length. This independence is a requirement in common classification problems ...
    • Nonstationary Signal Enhancement Using The Wavelet Transform 

      Venkatachalam, Vidya; Aravena, Jorge.L. (1996-03-20)
      Conventional signal processing typically involves frequency selective techniques which are highly inadequate for nonstationary signals. In this paper, we present an approach to perform time-frequency selective processing ...
    • Numerical Estimates of Generalized Dimensions D_q for Negative q 

      Riedi, Rudolf H. (1996-01-01)
      Usual fixed-size box-counting algorithms are inefficient for computing generalized fractal dimensions D(<i>q</i>) in the range of <i>q</i><0. In this Letter we describe a new numerical algorithm specifically devised to ...