Now showing items 1-20 of 110

    • 2-D Locally Regularized Tissue Strain Estimation From Radio-Frequency Ultrasound Images: Theoretical Developments and Results on Experimental Data 

      Author: Brusseau, Elisabeth; Kybic, Jan; Déprez, Jean-François; Basset, Olivier
      (IEEE, 2008-02)
      In this paper, a 2-D locally regularized strain estimation method for imaging deformation of soft biological tissues from radio-frequency (RF) ultrasound (US) data is introduced. Contrary to most 2-D techniques that model ...
    • 3D Ultrasound real-time monitoring of surgical tools 

      Author: Gaufillet, Fabian; Liebgott, Hervé; Uherčík, Marián; Cervenansky, Fréderic; Kybic, Jan; Cachard, Christian
      (IEEE, 2010-10)
      To assist surgeons during their surgical operations, which involve a tool insertion, a real-time application which is able to localise the surgical tool during its movement is proposed. The position of the needle is estimated ...
    • A common formalism for the integral formulations of the forward EEG problem 

      Author: Kybic, Jan; Clerc, Maureen; Abboud, Toufic; Faugeras, Olivier; Keriven, Renaud; Papadopoulo, Théo
      (IEEE, 2005-01)
      The forward electroencephalography (EEG) problem involves finding a potential V from the Poisson equation ∇·(σ∇V)=f, in which f represents electrical sources in the brain, and σ the conductivity of the head tissues. In the ...
    • A Linear Programming Approach to Max-sum Problem: A Review 

      Author: Werner, Tomáš
      (Center for Machine Perception, Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University, 2005-12)
      The max-sum labeling problem, de ned as maximizing a sum of functions of pairs of discrete variables, is a general optimization problem with numerous applications, e.g., computing MAP assignments of a Markov random eld. ...
    • A voting strategy for visual ego-motion from stereo 

      Author: Obdržálek, Štěpán; Matas, Jiří
      (IEEE, 2010-06)
      We present a procedure for egomotion estimation from visual input of a stereo pair of video cameras. The 3D egomotion problem, which has six degrees of freedom in general, is simplified to four dimensions and further ...
    • Active Testing Search for Point Cloud Matching 

      Author: Amável Pinheiro, Miguel; Sznitman, Raphael; Serradell, Eduard; Kybic, Jan; Moreno-Noguer, Francesc; Fua, Pascal
      (Springer, 2013)
      We present a general approach for solving the point-cloud matching problem for the case of mildly nonlinear transformations. Our method quickly nds a coarse approximation of the solution by exploring a reduced set of ...
    • AdaBoost with Totally Corrective Updates for Fast Face Detection 

      Author: Šochman, Jan; Matas, Jiří
      (IEEE, 2004-05)
      An extension of the AdaBoost learning algorithm is proposed and brought to bear on the face detection problem. In each weak classifier selection cycle, the novel totally corrective algorithm reduces aggressively the upper ...
    • Adaptive Parameter Optimization for Real-time Tracking 

      Author: Zimmermann, Karel; Svoboda, Tomáš; Matas, Jiří
      (IEEE, 2007-10)
      Adaptation of a tracking procedure combined in a common way with a Kalman filter is formulated as an constrained optimization problem, where a trade-off between precision and loss-of-lock probability is explicitly taken ...
    • Audio-Visual Person Verification 

      Author: Ben-Yacoub, S.; Luttin, J.; Jonsson, K.; Matas, J.; Kittler, J.
      (IEEE, 1999)
      In this paper we investigate benefits of classifier combination (fusion) for a multimodal system for personal identity verification. The system uses frontal face images and speech. We show that a sophisticated fusion ...
    • Automatic FPGA based implementation of a classification tree 

      Author: Mitéran, J.; Matas, J.; Dubois, J.; Bourennane, E.
      (IEEE, 2004)
      We propose a method of automatic hardware implementation of a decision rule based on the Adaboost algorithm. We review the principles of the classification method and we evaluate its hardware implementation cost in term ...
    • Bootstrap Optical Flow Confidence and Uncertainty Measure 

      Author: Kybic, Jan; Nieuwenhuis, Claudia
      (Elsevier, 2011)
      We address the problem of estimating the uncertainty of optical flow algorithm results. Our method estimates the error magnitude at all points in the image. It can be used as a confidence measure. It is based on bootstrap ...
    • Bootstrap Resampling for Image Registration Uncertainty Estimation Without Ground Truth 

      Author: Kybic, Jan
      (IEEE, 2010-01)
      We address the problem of estimating the uncertainty of pixel based image registration algorithms, given just the two images to be registered, for cases when no ground truth data is available. Our novel method uses bootstrap ...
    • Characterization of Complex Fractionated Atrial Electrograms by Sample Entropy: An International Multi-Center Study 

      Author: Novák, Daniel
      Atrial fibrillation (AF) is the most commonly clinically-encountered arrhythmia. Catheter ablation of AF is mainly based on trigger elimination and modification of the AF substrate. Substrate mapping ablation of complex ...
    • Classification of microscopy images of Langerhans islets 

      Author: Švihlík, Jan; Kybic, Jan; Habart, David; Berková, Zuzana; Girman, Peter; Kříž, Jan; Zacharovová, Klára
      (SPIE, 2014)
      Evaluation of images of Langerhans islets is a crucial procedure for planning an islet transplantation, which is a promising diabetes treatment. This paper deals with segmentation of microscopy images of Langerhans islets ...
    • Colour-Based Object Recognition for Video Annotation 

      Author: Koubaroulis, Dirnitrios; Matas, Jiří; Kittler, Josef
      (IEEE, 2002)
      We propose a colour-based object recognition method for video annotation. The semantic gap between image measurements and symbolic labelling is bridged by assuming the existence of objects whose appearance can be associated ...
    • Comparison of face verification results on the XM2VTS database 

      Author: Matas, J.; Hamouz, M.; Jonsson, K.; Kittler, J.; Li, Y.; Kotropoulos, C.; Tefas, A.; Pitas, I.; Teewoon Tan; Hong Yan; Smeraldi, F.; Bigun, J.; Capdevielle, N.; Gerstner, W.; Ben-Yacoub, S.; Abdeljaoued, Y.; Mayoraz, E.
      (IEEE, 2000)
      The pater presents results of the face verification contest that was organized in conjunction with International Conference on Pattern Recognition 2000. Participants had to use identical data sets from a large, publicly ...
    • Comparison of Methods for Tool Localization in Biological Tissue from 3D Ultrasound Data 

      Author: Barva, Martin; Kybic, Jan; Hlaváč, Václav; Liebgott, Hervé; Cachard, Christian
      (IEEE, 2006-10)
      In medical applications, miniature surgical instruments such as needles, or electrodes are introduced into human body. The position of instrument in tissue can be estimated using 3D ultrasound. In previous publications, ...
    • Construction of Precise Local Affine Frames 

      Author: Mikulik, Andrej; Matas, Jiří; Perd’och, Michal; Chum, Ondřej
      (IEEE, 2010-08)
      We propose a novel method for the refinement of Maximally Stable Extremal Region (MSER) boundaries to sub-pixel precision by taking into account the intensity function in the 2 × 2 neighborhood of the contour points. The ...
    • Dense Linear-Time Correspondences for Tracking 

      Author: Obdržálek, Štěpán; Perd’och, Michal; Matas, Jiří
      (IEEE, 2008-06)
      A novel method is proposed for the problem of frame-to-frame correspondence search in video sequences. The method, based on hashing of low-dimensional image descriptors, establishes dense correspondences and allows large ...
    • Dimension Selection in Axis-Parallel Brent-STEP Method for Black-Box Optimization of Separable Continuous Functions 

      Author: Pošík, Petr; Baudiš, Petr
      (ACM, 2015)
      The recently proposed Brent-STEP algorithm was gener alized for separable functions by performing axis-parallel searches, interleaving the steps in individual dimensions in a round-robin fashion. This article explores ...