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Author Jaume Garcia; Joel Barajas; Francesc Carreras; Sandra Pujades; Petia Radeva edit   pdf
doi  isbn
openurl 
  Title An intuitive validation technique to compare local versus global tagged MRI analysis Type Conference Article
  Year 2005 Publication Computers In Cardiology Abbreviated Journal  
  Volume 32 Issue Pages 29–32  
  Keywords  
  Abstract Myocardium appears as a uniform tissue that seen in convectional Magnetic Resonance Images (MRI) shows just the contractile part of its movement. MR Tagging is a unique imaging technique that prints a grid over the tissue which moves according to the underlying movement of the myocardium revealing the true deformation of the cardiac muscle. Optical flow techniques based on spectral information estimate tissue displacement by analyzing information encoded in the phase maps which can be obtained using, local (Gabor) and global (HARP) methods. In this paper we compare both in synthetic and real Tagged MR sequences. We conclude that local method is slightly more accurate than the global one. On the other hand, global method is more efficient as it is much faster and less parameters have to be taken into account  
  Address Lyon (France)  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 0-7803-9337-6 Medium  
  Area Expedition Conference  
  Notes IAM;MILAB Approved no  
  Call Number IAM @ iam @ GBC2005 Serial 639  
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Author Petia Radeva; A.Amini; J.Huang; Enric Marti edit   pdf
url  doi
isbn  openurl
  Title Deformable B-Solids and Implicit Snakes for Localization and Tracking of SPAMM MRI-Data Type Conference Article
  Year 1996 Publication Workshop on Mathematical Methods in Biomedical Image Analysis Abbreviated Journal  
  Volume Issue Pages 192-201  
  Keywords  
  Abstract To date, MRI-SPAMM data from different image slices have been analyzed independently. In this paper, we propose an approach for 3D tag localization and tracking of SPAMM data by a novel deformable B-solid. The solid is defined in terms of a 3D tensor product B-spline. The isoparametric curves of the B-spline solid have special importance. These are termed implicit snakes as they deform under image forces from tag lines in different image slices. The localization and tracking of tag lines is performed under constraints of continuity and smoothness of the B-solid. The framework unifies the problems of localization, and displacement fitting and interpolation into the same procedure utilizing B-spline bases for interpolation. To track motion from boundaries and restrict image forces to the myocardium, a volumetric model is employed as a pair of coupled endocardial and epicardial B-spline surfaces. To recover deformations in the LV an energy-minimization problem is posed where both tag and ...  
  Address San Francisco CA  
  Corporate Author Thesis  
  Publisher IEEE Computer Society Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 0-8186-7368-0 Medium  
  Area Expedition Conference MMBIA ’96  
  Notes MILAB;IAM; Approved no  
  Call Number IAM @ iam @ RAH1996 Serial 1630  
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Author Joel Barajas; Jaume Garcia; Francesc Carreras; Sandra Pujades; Petia Radeva edit   pdf
url  isbn
openurl 
  Title Angle Images Using Gabor Filters in Cardiac Tagged MRI Type Conference Article
  Year 2005 Publication Proceeding of the 2005 conference on Artificial Intelligence Research and Development Abbreviated Journal  
  Volume Issue Pages 107-114  
  Keywords Angle Images, Gabor Filters, Harp, Tagged Mri  
  Abstract Tagged Magnetic Resonance Imaging (MRI) is a non-invasive technique used to examine cardiac deformation in vivo. An Angle Image is a representation of a Tagged MRI which recovers the relative position of the tissue respect to the distorted tags. Thus cardiac deformation can be estimated. This paper describes a new approach to generate Angle Images using a bank of Gabor filters in short axis cardiac Tagged MRI. Our method improves the Angle Images obtained by global techniques, like HARP, with a local frequency analysis. We propose to use the phase response of a combination of a Gabor filters bank, and use it to find a more precise deformation of the left ventricle. We demonstrate the accuracy of our method over HARP by several experimental results.  
  Address Amsterdam; The Netherlands  
  Corporate Author Thesis  
  Publisher IOS Press Place of Publication Amsterdam, The Netherlands Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 1-58603-560-6 Medium  
  Area Expedition Conference CAIRD  
  Notes IAM;MILAB Approved no  
  Call Number BCNPCL @ bcnpcl @ BGC2005; IAM @ iam Serial 595  
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Author Debora Gil; Petia Radeva edit   pdf
url  doi
isbn  openurl
  Title Curvature Vector Flow to Assure Convergent Deformable Models for Shape Modelling Type Book Chapter
  Year 2003 Publication Energy Minimization Methods In Computer Vision And Pattern Recognition Abbreviated Journal LNCS  
  Volume 2683 Issue Pages 357-372  
  Keywords Initial condition; Convex shape; Non convex analysis; Increase; Segmentation; Gradient; Standard; Standards; Concave shape; Flow models; Tracking; Edge detection; Curvature  
  Abstract Poor convergence to concave shapes is a main limitation of snakes as a standard segmentation and shape modelling technique. The gradient of the external energy of the snake represents a force that pushes the snake into concave regions, as its internal energy increases when new inexion points are created. In spite of the improvement of the external energy by the gradient vector ow technique, highly non convex shapes can not be obtained, yet. In the present paper, we develop a new external energy based on the geometry of the curve to be modelled. By tracking back the deformation of a curve that evolves by minimum curvature ow, we construct a distance map that encapsulates the natural way of adapting to non convex shapes. The gradient of this map, which we call curvature vector ow (CVF), is capable of attracting a snake towards any contour, whatever its geometry. Our experiments show that, any initial snake condition converges to the curve to be modelled in optimal time.  
  Address  
  Corporate Author Thesis  
  Publisher Springer, Berlin Place of Publication Lisbon, PORTUGAL Editor Springer, B.  
  Language Summary Language Original Title  
  Series Editor Series Title Lecture Notes in Computer Science Abbreviated Series Title LNCS  
  Series Volume Series Issue Edition  
  ISSN 0302-9743 ISBN (up) 3-540-40498-8 Medium  
  Area Expedition Conference  
  Notes IAM;MILAB Approved no  
  Call Number IAM @ iam @ GIR2003b Serial 1535  
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Author Josep Llados; Ernest Valveny; Gemma Sanchez; Enric Marti edit   pdf
url  doi
isbn  openurl
  Title Symbol recognition: current advances and perspectives Type Book Chapter
  Year 2002 Publication Graphics Recognition Algorithms And Applications Abbreviated Journal LNCS  
  Volume 2390 Issue Pages 104-128  
  Keywords  
  Abstract The recognition of symbols in graphic documents is an intensive research activity in the community of pattern recognition and document analysis. A key issue in the interpretation of maps, engineering drawings, diagrams, etc. is the recognition of domain dependent symbols according to a symbol database. In this work we first review the most outstanding symbol recognition methods from two different points of view: application domains and pattern recognition methods. In the second part of the paper, open and unaddressed problems involved in symbol recognition are described, analyzing their current state of art and discussing future research challenges. Thus, issues such as symbol representation, matching, segmentation, learning, scalability of recognition methods and performance evaluation are addressed in this work. Finally, we discuss the perspectives of symbol recognition concerning to new paradigms such as user interfaces in handheld computers or document database and WWW indexing by graphical content.  
  Address London, UK  
  Corporate Author Thesis  
  Publisher Springer-Verlag Place of Publication Editor Dorothea Blostein and Young- Bin Kwon  
  Language Summary Language Original Title  
  Series Editor Series Title Lecture Notes in Computer Science Abbreviated Series Title LNCS  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 3-540-44066-6 Medium  
  Area Expedition Conference GREC  
  Notes DAG; IAM; Approved no  
  Call Number IAM @ iam @ LVS2002 Serial 1572  
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Author Josep Llados; Ernest Valveny; Enric Marti edit  isbn
openurl 
  Title Symbol Recognition in Document Image Analysis: Methods and Challenges Type Journal Article
  Year 2000 Publication Recent Research Developments in Pattern Recognition, Transworld Research Network, Abbreviated Journal  
  Volume 1 Issue Pages 151–178.  
  Keywords  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 81-86846-61-1 Medium  
  Area Expedition Conference  
  Notes DAG;IAM Approved no  
  Call Number IAM @ iam @ LVM2000 Serial 1575  
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Author Debora Gil edit   pdf
isbn  openurl
  Title Geometric Differential Operators for Shape Modelling Type Book Whole
  Year 2004 Publication PhD Thesis, Universitat Autonoma de Barcelona-CVC Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract Medical imaging feeds research in many computer vision and image processing fields: image filtering, segmentation, shape recovery, registration, retrieval and pattern matching. Because of their low contrast changes and large variety of artifacts and noise, medical imaging processing techniques relying on an analysis of the geometry of image level sets rather than on intensity values result in more robust treatment. From the starting point of treatment of intravascular images, this PhD thesis ad- dresses the design of differential image operators based on geometric principles for a robust shape modelling and restoration. Among all fields applying shape recovery, we approach filtering and segmentation of image objects. For a successful use in real images, the segmentation process should go through three stages: noise removing, shape modelling and shape recovery. This PhD addresses all three topics, but for the sake of algorithms as automated as possible, techniques for image processing will be designed to satisfy three main principles: a) convergence of the iterative schemes to non-trivial states avoiding image degeneration to a constant image and representing smooth models of the originals; b) smooth asymptotic behav- ior ensuring stabilization of the iterative process; c) fixed parameter values ensuring equal (domain free) performance of the algorithms whatever initial images/shapes. Our geometric approach to the generic equations that model the different processes approached enables defining techniques satisfying all the former requirements. First, we introduce a new curvature-based geometric flow for image filtering achieving a good compromise between noise removing and resemblance to original images. Sec- ond, we describe a new family of diffusion operators that restrict their scope to image level curves and serve to restore smooth closed models from unconnected sets of points. Finally, we design a regularization of snake (distance) maps that ensures its smooth convergence towards any closed shape. Experiments show that performance of the techniques proposed overpasses that of state-of-the-art algorithms.  
  Address  
  Corporate Author Thesis Ph.D. thesis  
  Publisher Ediciones Graficas Rey Place of Publication Barcelona (Spain) Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 84-933652-0-3 Medium prit  
  Area Expedition Conference  
  Notes IAM; Approved no  
  Call Number IAM @ iam @ GIL2004 Serial 1517  
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Author Enric Marti; Jordi Vitria; Alberto Sanfeliu edit   pdf
isbn  openurl
  Title Reconocimiento de Formas y Análisis de Imágenes Type Book Whole
  Year 1998 Publication Asociación Española de Reconocimientos de Formas y Análisis de Imágenes Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract Los sistemas actuales de reconocimiento automático del lenguaje oral se basan en dos etapas básicas de procesado: la parametrización, que extrae la evolución temporal de los parámetros que caracterizan la voz, y el reconocimiento propiamente dicho, que identifica la cadena de palabras de la elocución recibida con ayuda de los modelos que representan el conocimiento adquirido en la etapa de aprendizaje. Tomando como línea divisoria la palabra, dichos modelos son de tipo acústicofonético o gramatical. Los primeros caracterizan las palabras incluidas en el vocabulario de la aplicación o tarea a la que está orientado el sistema de reconocimiento, usando a menudo para ello modelos de unidades de habla de extensión inferior a la palabra, es decir, de unidades subléxicas. Por otro lado, la gramática incluye el conocimiento acerca de las combinaciones permitidas de palabras para formar las frases o su probabilidad. Queda fuera del esquema la denominada comprensión del habla, que utiliza adicionalmente el conocimiento semántico y pragmático para captar el significado de la elocución de entrada al sistema a partir de la cadena (o cadenas alternativas) de palabras que suministra el reconocedor.  
  Address  
  Corporate Author Thesis  
  Publisher AERFAI Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 84–922529–4–4 Medium  
  Area Expedition Conference  
  Notes IAM;OR;MV Approved no  
  Call Number IAM @ iam @ MVS1998 Serial 1620  
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Author Josep Llados; Ernest Valveny; Gemma Sanchez; Enric Marti edit  url
isbn  openurl
  Title A Case Study of Pattern Recognition: Symbol Recognition in Graphic Documentsa Type Conference Article
  Year 2003 Publication Proceedings of Pattern Recognition in Information Systems Abbreviated Journal  
  Volume Issue Pages 1-13  
  Keywords  
  Abstract  
  Address Angers, France  
  Corporate Author Thesis  
  Publisher ICEIS Press Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 972-98816-3-4 Medium  
  Area Expedition Conference PRIS'03  
  Notes DAG;IAM; Approved no  
  Call Number IAM @ iam @ LVS2003 Serial 1576  
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Author Jaume Garcia; Albert Andaluz; Debora Gil; Francesc Carreras edit   pdf
url  doi
isbn  openurl
  Title Decoupled External Forces in a Predictor-Corrector Segmentation Scheme for LV Contours in Tagged MR Images Type Conference Article
  Year 2010 Publication 32nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society Abbreviated Journal  
  Volume Issue Pages 4805-4808  
  Keywords  
  Abstract Computation of functional regional scores requires proper identification of LV contours. On one hand, manual segmentation is robust, but it is time consuming and requires high expertise. On the other hand, the tag pattern in TMR sequences is a problem for automatic segmentation of LV boundaries. We propose a segmentation method based on a predictorcorrector (Active Contours – Shape Models) scheme. Special stress is put in the definition of the AC external forces. First, we introduce a semantic description of the LV that discriminates myocardial tissue by using texture and motion descriptors. Second, in order to ensure convergence regardless of the initial contour, the external energy is decoupled according to the orientation of the edges in the image potential. We have validated the model in terms of error in segmented contours and accuracy of regional clinical scores.  
  Address Buenos Aires (Argentina)  
  Corporate Author IEEE EMB Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1557-170X ISBN (up) 978-1-4244-4123-5 Medium  
  Area Expedition Conference EMBC  
  Notes IAM Approved no  
  Call Number IAM @ iam @ GAG2010 Serial 1514  
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