Now showing items 45-64 of 210

    • The Effect of Local Fiber Model On Population Studies 

      Malcolm, James G.; Kubicki, Marek; Shenton, Martha E.; Rathi, Yogesh (Georgia Institute of Technology, 2009-09-24)
      Diffusion tensor imaging has made it possible to evaluate the organization and coherence of white matter fiber tracts. Hence, it has been used in many population studies, most notably, to find abnormalities in schizophrenia. ...
    • An efficient lapped orthogonal transform image coding technique 

      Kumar, Sunil; Rathi, Yogesh; Jain, R. C. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 1997-11)
      A fast and computationally less complex coding technique is described which uses partial-lapped orthogonal transform (LOT) computation algorithm and efficiently discards perceptually insignificant high frequency transform ...
    • An efficient numerical method for the solution of the L₂optimal mass transfer problem 

      Haber, Eldad; Rehman, Tauseef ur; Tannenbaum, Allen R. (Georgia Institute of TechnologySociety for Industrial and Applied Mathematics, 2010-02-05)
      In this paper we present a new computationally efficient numerical scheme for the minimizing flow approach for the computation of the optimal L₂mass transport mapping. In contrast to the integration of a time dependent ...
    • Expanded Pharmacokinetic model for population studies in Breast MRI 

      Mohan, Vandana; Shinagawa, Yoshihisa; Jian, Bing; Hermosillo Valadez, Gerardo (Georgia Institute of TechnologySociety of Photo-Optical Instrumentation Engineers, 2008-02-19)
      We propose a new model for pharmacokinetic analysis based on the one proposed by Tofts. Our model both eliminates the need for estimating the Arterial Input Function (AIF) and normalizes analysis so that comparisons across ...
    • Experiments on geometric image enhancement 

      Sapiro, Guillermo; Tannenbaum, Allen R.; You, Yu-La; Kaveh, Mos (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 1994-11)
      In this paper we experiment with geometric algorithms for image smoothing. Examples are given for MRI and ATR data. We emphasize experiments with the affine invariant geometric smoother or affine heat equation, originally ...
    • Expressive Autonomous Cinematography for Interactive Virtual Environments 

      Tomlinson, Bill; Blumberg, Bruce; Nain, Delphine (Georgia Institute of TechnologyAssociation for Computing Machinery (ACM), 2000-06)
      We have created an automatic cinematography system for interactive virtual environments. This system controls a virtual camera and lights in a three-dimensional virtual world inhabited by a group of autonomous and ...
    • Fast approximate curve evolution 

      Malcolm, James G.; Rathi, Yogesh; Yezzi, Anthony; Tannenbaum, Allen R. (Georgia Institute of TechnologySociety of Photo-Optical Instrumentation Engineers, 2008-01)
      The level set method for curve evolution is a popular technique used in image processing applications. However, the numerics involved make its use in high performance systems computationally prohibitive. This paper proposes ...
    • Fast approximate surface evolution in arbitrary dimension 

      Malcolm, James G.; Rathi, Yogesh; Yezzi, Anthony; Tannenbaum, Allen R. (Georgia Institute of TechnologySociety of Photo-Optical Instrumentation Engineers, 2008-02)
      The level set method is a popular technique used in medical image segmentation; however, the numerics involved make its use cumbersome. This paper proposes an approximate level set scheme that removes much of the computational ...
    • Fast Multigrid Optimal Mass Transport for Image Registration and Morphing 

      Rehman, Tauseef ur; Pryor, Gallagher D.; Tannenbaum, Allen R. (Georgia Institute of TechnologyBritish Machine Vision Association, 2007-09)
      In this paper we present a novel, computationally efficient algorithm for nonrigid 2D image registration based on the work of Haker et al.[1, 2]. We formulate the registration task as an Optimal Mass Transport (OMT) problem ...
    • Fast Optimal Mass Transport for Dynamic Active Contour Tracking on the GPU 

      Pryor, Gallagher D.; Rehman, Tauseef ur; Lankton, Shawn; Vela, Patricio A.; Tannenbaum, Allen R. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2007-12)
      In computational vision, visual tracking remains one of the most challenging problems due to noise, clutter, occlusion, and dynamic scenes. No one technique has yet managed to solve this problem completely, but those that ...
    • Filtered Multitensor Tractography 

      Malcolm, James G.; Shenton, Martha E.; Rathi, Yogesh (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2010-09)
      We describe a technique that uses tractography to drive the local fiber model estimation. Existing techniques use independent estimation at each voxel so there is no running knowledge of confidence in the estimated model ...
    • Filtered Tractography: State estimation in a constrained subspace 

      Malcolm, James G.; Shenton, Martha E.; Rathi, Yogesh (Georgia Institute of Technology, 2009-09-24)
      We describe amethod of deterministic tractography using model-based estimation that remains constrained to the subspace of valid tensor mixture models. Existing techniques estimate the local fiber orientation at each ...
    • Filtered Tractography: Validation on a Physical Phantom 

      Malcolm, James G.; Shenton, Martha E.; Rathi, Yogesh (Georgia Institute of Technology, 2009-09-24)
      This note summarizes a technique that uses tractography to drive the local fiber model estimation. Existing techniques use independent estimation at each voxel so there is no running knowledge of confidence in the estimated ...
    • Finsler Active Contours 

      Melonakos, John; Pichon, Eric; Angenent, Sigurd; Tannenbaum, Allen R. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2008-03)
      In this paper, we propose an image segmentation technique based on augmenting the conformal (or geodesic) active contour framework with directional information. In the isotropic case, the euclidean metric is locally ...
    • Finsler Level Set Segmentation for Imagery in Oriented Domains 

      Mohan, Vandana; Melonakos, John; Niethammer, Marc; Kubicki, Marek; Tannenbaum, Allen R. (Georgia Institute of TechnologyBritish Machine Vision Association, 2009-09)
      In this paper, we present a novel directional level set segmentation framework employing the theory of Finsler active contours. The framework provides a natural way to perform segmentation of image data in oriented domains. ...
    • Flattening Maps for the Visualization of Multibranched Vessels 

      Zhu, Lei; Haker, Steven; Tannenbaum, Allen R. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2005-02)
      In this paper, we present two novel algorithms which produce flattened visualizations of branched physiological surfaces, such as vessels. The first approach is a conformal mapping algorithm based on the minimization of ...
    • Flow Patterns and Wall Shear Stress Distributions at Atherosclerotic-Prone Sites in a Human Left Coronary Artery - An Exploration Using Combined Methods of CT and Computational Fluid Dynamics 

      Jin, Suo; Yang, Yan; Oshinski, John N.; Tannenbaum, Allen R.; Gruden, James; Giddens, Don P. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2004-09)
      Computed tomography (CT) slices are combined with computational fluid dynamics (CFD) to simulate the flow patterns in a human left coronary artery. The vascular model was reconstructed from CT slices scanned from a healthy ...
    • Flux driven fly-throughs 

      Bouix, Sylvain; Siddiqi, Kaleem; Tannenbaum, Allen R. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2003-06)
      We present a fast, robust and automatic method for computing central paths through tubular structures for application to virtual endoscopy. The key idea is to utilize a medial surface algorithm, which exploits properties ...
    • Formulating Invariant Heat-Type Curve Flows 

      Sapiro, Guillermo; Tannenbaum, Allen R. (Georgia Institute of TechnologyInternational Society for Optical Engineering, 1993-07-12)
      We describe a geometric method for formulating planar curve evolution equations which are invariant under a certain transformation group. The approach is based on concepts from the classical theory of differential invariants. ...
    • The four block problem for distributed systems 

      Foias, Ciprian; Tannenbaum, Allen R. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 1988-12)
      A study is made of the singular values of the four-block operator, which appears naturally in many H∞ control problems. Following the framework of the monograph of B.A. Francis (1987), almost all such robust design problems ...