Now showing items 214-233 of 508

  • Lattice Algorithms for Compression Color Space Estimation in JPEG Images 

    Neelamani, Ramesh; de Queiroz, Ricardo; Baraniuk, Richard G. (2001-08-01)
    JPEG (Joint Photographic Experts Group) is an international standard to compress and store digital color images [5]. Given a color image that was previously JPEG-compressed in some hidden color space, we aim to estimate ...
  • Learning minimum volume sets with support vector machines 

    Davenport, Mark A.; Baraniuk, Richard G.; Scott, Clayton D. (2006-09-01)
    Given a probability law P on d-dimensional Euclidean space, the minimum volume set (MV-set) with mass beta , 0 < beta < 1, is the set with smallest volume enclosing a probability mass of at least beta. We examine the use ...
  • Lifting Construction of Non-Linear Wavelet Transforms 

    Claypoole, Roger L.; Baraniuk, Richard G.; Nowak, Robert David (1998-10-01)
    This paper analyzes non-linear wavelet transforms using the lifting construction. The lifting construction exploits a spatial-domain, prediction-error interpretation of the wavelet transform and provides a powerful framework ...
  • A Limitation of the Kernel Method for Joint Distributions of Arbitrary Variables 

    Baraniuk, Richard G. (1996-02-01)
    Recently, Cohen has proposed a construction for joint distributions of arbitrary physical quantities, in direct generalization of joint time-frequency representations. Actually this method encompasses two approaches, one ...
  • Limits of population coding 

    Johnson, Don (2003-07-20)
    To understand whether the population response expresses information better than the aggregate of the individual responses, the sum of the individual contributions is frequently used as a baseline against which to assess ...
  • Locating Available Bandwidth Bottlenecks 

    Ribeiro, Vinay Joseph; Riedi, Rudolf H.; Baraniuk, Richard G. (2004-09-01)
    The Spatio-temporal Available Bandwidth estimator (STAB), a new edge-based probing tool, locates thin links --- those links with less available bandwidth than all links preceeding them --- on end-to-end network paths. By ...
  • Long-Range Dependence: Now you see it now you don't! 

    Karagiannis , Thomas; Faloutsos , Michalis; Riedi, Rudolf H. (2002-11-20)
    Over the last few years, the network community has started to rely heavily on the use of novel concepts such as self-similarity and Long-Range Dependence (LRD). Despite their wide use, there is still much confusion regarding ...
  • Low Rank Estimation of Higher Order Statistics 

    Nowak, Robert David; Van Veen, Barry D. (1995-12-01)
    Low rank estimators for higher order statistics are considered in this paper. Rank reduction methods offer a general principle for trading estimator bias for reduced estimator variance. The bias-variance tradeoff is analyzed ...
  • M-Band Multiwavelet Systems 

    Burrus, C. Sidney; Fernandes, Felix (1999-03-20)
    In this paper we investigate multiwavelet systems whose scaling functions have disjoint support. We demonstrate that, with the exception of a trivial case, this property may not be attained by two band multiwavelet systems. ...
  • Magnitude Squared Design of Recursive Filters with the Chebyshev Norm Using a Constrained Rational Remez Algorithm 

    Selesnick, Ivan W.; Lang, Markus; Burrus, C. Sidney (1994-10-01)
    We describe a Remez type exchange algorithm for the design of stable recursive filters for which the Chebyschev norm of H(w) - F(w) is minimized, where H(w) and F(w) are the realized and desired magnitude squared frequency ...
  • Magnitude Squared Design of Recursive Filters with the Chebyshev Norm Using a Constrained Rational Remez Algorithm 

    Selesnick, Ivan W.; Lang, Markus; Burrus, C. Sidney (1994-05-01)
    We describe a Remez type exchange algorithm for the design of stable recursive filters for which the Chebyschev norm of H(w) - F(w) is minimized, where H(w) and F(w) are the realized and desired magnitude squared frequency ...
  • Magnitude Weighting and Time Segmentation for Phase-Only Reconstruction of Signals 

    Merchant, G.A.; Parks, T.W. (1981-04-01)
    Phase-only reconstruction of signals and its application to blind-deconvolution were introduced recently by Oppenheim, and by Hayes, et.al. In this report, we briefly present another description of this phase-only ...
  • Marginals vs. Covariance in Joint Distribution Theory 

    Baraniuk, Richard G. (1995-05-01)
    Recently, Cohen has proposed a method for constructing joint distributions of arbitrary physical quantities, in direct generalization of joint time-frequency representations. In this paper, we investigate the covariance ...
  • A Markov Chain Analysis of Blackjack Strategy 

    Wakin, Michael; Rozell, Chris (2004-07-01)
    Blackjack receives considerable attention from mathematicians and entrepreneurs alike, due to its simple rules, its inherent random nature, and the abundance of "prior" information available to an observant player. Many ...
  • Matrix Based Computation of Floating-Point Roundoff Noise 

    Van Veen, Barry D.; Baraniuk, Richard G. (1989-12-01)
    A matrix based procedure is presented for computing the output roundoff noise power for filters implemented with floating-point arithmetic. The filter's computational structure is represented in terms of a product of ...
  • Measurements vs. Bits: Compressed Sensing meets Information Theory 

    Sarvotham, Shriram; Baron, Dror; Baraniuk, Richard G. (2006-09-01)
    Compressed sensing is a new framework for acquiring sparse signals based on the revelation that a small number of linear projections (measurements) of the signal contain enough information for its reconstruction. The ...
  • Measuring Time-Frequency Information and Complexity using the Renyi Entropies 

    Baraniuk, Richard G.; Flandrin, Patrick; Michel, Olivier (1995-09-01)
    In search of a nonparametric indicator of deterministic signal complexity, we link the Renyi entropies to time-frequency representations. The resulting measures show promise in several situations where concepts like the ...
  • Measuring Time-Frequency Information Content using the Renyi Entropies 

    Baraniuk, Richard G.; Flandrin, Patrick; Janssen, A. J. E. M.; Michel, Olivier (2001-05-01)
    The generalized entropies of Renyi inspire new measures for estimating signal information and complexity in the time-frequency plane. When applied to a time-frequency representation (TFR) from Cohen's class or the affine ...
  • Minimax support vector machines 

    Davenport, Mark A.; Baraniuk, Richard G.; Scott, Clayton D. (2007-08-01)
    We study the problem of designing support vector machine (SVM) classifiers that minimize the maximum of the false alarm and miss rates. This is a natural classification setting in the absence of prior information regarding ...
  • Model-based Inverse Halftoning with Wavelet-Vaguelette Deconvolution 

    Neelamani, Ramesh; Nowak, Robert David; Baraniuk, Richard G. (2000-09-01)
    In this paper, we demonstrate based on the linear model of Kite that inverse halftoning is equivalent to the well-studied problem of deconvolution in the presence of colored noise. We propose the use of the simple and ...