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Author | Debora Gil; Jaume Garcia; Aura Hernandez-Sabate; Enric Marti | ||||
Title | Manifold parametrization of the left ventricle for a statistical modelling of its complete anatomy | Type | Conference Article | ||
Year | 2010 | Publication | 8th Medical Imaging | Abbreviated Journal | |
Volume | 7623 | Issue | 762304 | Pages | 304 |
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Abstract | Distortion of Left Ventricle (LV) external anatomy is related to some dysfunctions, such as hypertrophy. The architecture of myocardial fibers determines LV electromechanical activation patterns as well as mechanics. Thus, their joined modelling would allow the design of specific interventions (such as peacemaker implantation and LV remodelling) and therapies (such as resynchronization). On one hand, accurate modelling of external anatomy requires either a dense sampling or a continuous infinite dimensional approach, which requires non-Euclidean statistics. On the other hand, computation of fiber models requires statistics on Riemannian spaces. Most approaches compute separate statistical models for external anatomy and fibers architecture. In this work we propose a general mathematical framework based on differential geometry concepts for computing a statistical model including, both, external and fiber anatomy. Our framework provides a continuous approach to external anatomy supporting standard statistics. We also provide a straightforward formula for the computation of the Riemannian fiber statistics. We have applied our methodology to the computation of complete anatomical atlas of canine hearts from diffusion tensor studies. The orientation of fibers over the average external geometry agrees with the segmental description of orientations reported in the literature. | ||||
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Corporate Author | Thesis | ||||
Publisher | SPIE | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | SPIE | ||
Notes | IAM | Approved | no | ||
Call Number | IAM @ iam @ GGH2010a | Serial | 1522 | ||
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Author | Jaume Garcia; Debora Gil; Luis Badiella; Aura Hernandez-Sabate; Francesc Carreras; Sandra Pujades; Enric Marti | ||||
Title | A Normalized Framework for the Design of Feature Spaces Assessing the Left Ventricular Function | Type | Journal Article | ||
Year | 2010 | Publication | IEEE Transactions on Medical Imaging | Abbreviated Journal | TMI |
Volume | 29 | Issue | 3 | Pages | 733-745 |
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Abstract | A through description of the left ventricle functionality requires combining complementary regional scores. A main limitation is the lack of multiparametric normality models oriented to the assessment of regional wall motion abnormalities (RWMA). This paper covers two main topics involved in RWMA assessment. We propose a general framework allowing the fusion and comparison across subjects of different regional scores. Our framework is used to explore which combination of regional scores (including 2-D motion and strains) is better suited for RWMA detection. Our statistical analysis indicates that for a proper (within interobserver variability) identification of RWMA, models should consider motion and extreme strains. | ||||
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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 | 0278-0062 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | IAM | Approved | no | ||
Call Number | IAM @ iam @ GGH2010b | Serial | 1507 | ||
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Author | Jaume Garcia; Debora Gil; Aura Hernandez-Sabate | ||||
Title | Endowing Canonical Geometries to Cardiac Structures | Type | Book Chapter | ||
Year | 2010 | Publication | Statistical Atlases And Computational Models Of The Heart | Abbreviated Journal | |
Volume | 6364 | Issue | Pages | 124-133 | |
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Abstract | International conference on Cardiac electrophysiological simulation challenge
In this paper, we show that canonical (shape-based) geometries can be endowed to cardiac structures using tubular coordinates defined over their medial axis. We give an analytic formulation of these geometries by means of B-Splines. Since B-Splines present vector space structure PCA can be applied to their control points and statistical models relating boundaries and the interior of the anatomical structures can be derived. We demonstrate the applicability in two cardiac structures, the 3D Left Ventricular volume, and the 2D Left-Right ventricle set in 2D Short Axis view. |
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Publisher | Springer Berlin / Heidelberg | Place of Publication | Editor | Camara, O.; Pop, M.; Rhode, K.; Sermesant, M.; Smith, N.; Young, A. | |
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 | Medium | |||
Area | Expedition | Conference | |||
Notes | IAM | Approved | no | ||
Call Number | IAM @ iam @ GGH2010b | Serial | 1515 | ||
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Author | Sandra Pujades;Francesc Carreras;Manuel Ballester; Jaume Garcia; Debora Gil | ||||
Title | A Normalized Parametric Domain for the Analysis of the Left Ventricular Function | Type | Conference Article | ||
Year | 2008 | Publication | Proceedings of the Third International Conference on Computer Vision Theory and Applications (VISAPP’08) | Abbreviated Journal | |
Volume | 1 | Issue | Pages | 267-274 | |
Keywords | Helical Ventricular Myocardial Band; Myocardial Fiber; Tagged Magnetic Resonance; HARP; Optical Flow Variational Framework; Gabor Filters; B-Splines. | ||||
Abstract | Impairment of left ventricular (LV) contractility due to cardiovascular diseases is reflected in LV motion patterns. The mechanics of any muscle strongly depends on the spatial orientation of its muscular fibers since the motion that the muscle undergoes mainly takes place along the fiber. The helical ventricular myocardial band (HVMB) concept describes the myocardial muscle as a unique muscular band that twists in space in a non homogeneous fashion. The 3D anisotropy of the ventricular band fibers suggests a regional analysis of the heart motion. Computation of normality models of such motion can help in the detection and localization of any cardiac disorder. In this paper we introduce, for the first time, a normalized parametric domain that allows comparison of the left ventricle motion across patients. We address, both, extraction of the LV motion from Tagged Magnetic Resonance images, as well as, defining a mapping of the LV to a common normalized domain. Extraction of normality motion patterns from 17 healthy volunteers shows the clinical potential of our LV parametrization. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | IAM; | Approved | no | ||
Call Number | IAM @ iam @ GGP2008 | Serial | 1627 | ||
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Author | Debora Gil; Jordi Gonzalez; Gemma Sanchez (eds) | ||||
Title | Computer Vision: Advances in Research and Development | Type | Book Whole | ||
Year | 2007 | Publication | Proceedings of the 2nd CVC International Workshop | Abbreviated Journal | |
Volume | Issue | Pages | |||
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Publisher | UAB | Place of Publication | Bellaterra (Spain) | Editor | Debora Gil; Jordi Gonzalez; Gemma Sanchez |
Language | Summary Language | Original Title | |||
Series Editor | Series Title | 2 | Abbreviated Series Title | ||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | 978-84-935251-4-9 | Medium | ||
Area | Expedition | Conference | |||
Notes | IAM; ISE; DAG | Approved | no | ||
Call Number | IAM @ iam @ GGS2007 | Serial | 1493 | ||
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Author | Debora Gil; Jaume Garcia; Mariano Vazquez; Ruth Aris; Guilleaume Houzeaux | ||||
Title | Patient-Sensitive Anatomic and Functional 3D Model of the Left Ventricle Function | Type | Conference Article | ||
Year | 2008 | Publication | 8th World Congress on Computational Mechanichs (WCCM8) | Abbreviated Journal | |
Volume | Issue | Pages | |||
Keywords | Left Ventricle, Electromechanical Models, Image Processing, Magnetic Resonance. | ||||
Abstract | Early diagnosis and accurate treatment of Left Ventricle (LV) dysfunction significantly increases the patient survival. Impairment of LV contractility due to cardiovascular diseases is reflected in its motion patterns. Recent advances in medical imaging, such as Magnetic Resonance (MR), have encouraged research on 3D simulation and modelling of the LV dynamics. Most of the existing 3D models [1] consider just the gross anatomy of the LV and restore a truncated ellipse which deforms along the cardiac cycle. The contraction mechanics of any muscle strongly depends on the spatial orientation of its muscular fibers since the motion that the muscle undergoes mainly takes place along the fibers. It follows that such simplified models do not allow evaluation of the heart electro-mechanical function and coupling, which has recently risen as the key point for understanding the LV functionality [2]. In order to thoroughly understand the LV mechanics it is necessary to consider the complete anatomy of the LV given by the orientation of the myocardial fibres in 3D space as described by Torrent Guasp [3].
We propose developing a 3D patient-sensitive model of the LV integrating, for the first time, the ven- tricular band anatomy (fibers orientation), the LV gross anatomy and its functionality. Such model will represent the LV function as a natural consequence of its own ventricular band anatomy. This might be decisive in restoring a proper LV contraction in patients undergoing pace marker treatment. The LV function is defined as soon as the propagation of the contractile electromechanical pulse has been modelled. In our experiments we have used the wave equation for the propagation of the electric pulse. The electromechanical wave moves on the myocardial surface and should have a conductivity tensor oriented along the muscular fibers. Thus, whatever mathematical model for electric pulse propa- gation [4] we consider, the complete anatomy of the LV should be extracted. The LV gross anatomy is obtained by processing multi slice MR images recorded for each patient. Information about the myocardial fibers distribution can only be extracted by Diffusion Tensor Imag- ing (DTI), which can not provide in vivo information for each patient. As a first approach, we have Figure 1: Scheme for the Left Ventricle Patient-Sensitive Model. computed an average model of fibers from several DTI studies of canine hearts. This rough anatomy is the input for our electro-mechanical propagation model simulating LV dynamics. The average fiber orientation is updated until the simulated LV motion agrees with the experimental evidence provided by the LV motion observed in tagged MR (TMR) sequences. Experimental LV motion is recovered by applying image processing, differential geometry and interpolation techniques to 2D TMR slices [5]. The pipeline in figure 1 outlines the interaction between simulations and experimental data leading to our patient-tailored model. |
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Address | Venice; Italy | ||||
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 | 9788496736559 | Medium | ||
Area | Expedition | Conference | |||
Notes | IAM; | Approved | no | ||
Call Number | IAM @ iam @ GGV2008b | Serial | 993 | ||
Permanent link to this record | |||||
Author | Debora Gil; Jaume Garcia; Manuel Vazquez; Ruth Aris; Guillaume Houzeaux | ||||
Title | Patient-Sensitive Anatomic and Functional 3D Model of the Left Ventricle Function | Type | Conference Article | ||
Year | 2008 | Publication | 8th World Congress on Computational Mechanichs (WCCM8)/5th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2008) | Abbreviated Journal | |
Volume | Issue | Pages | |||
Keywords | Left Ventricle; Electromechanical Models; Image Processing; Magnetic Resonance. | ||||
Abstract | Early diagnosis and accurate treatment of Left Ventricle (LV) dysfunction significantly increases the patient survival. Impairment of LV contractility due to cardiovascular diseases is reflected in its motion patterns. Recent advances in medical imaging, such as Magnetic Resonance (MR), have encouraged research on 3D simulation and modelling of the LV dynamics. Most of the existing 3D models consider just the gross anatomy of the LV and restore a truncated ellipse which deforms along the cardiac cycle. The contraction mechanics of any muscle strongly depends on the spatial orientation of its muscular fibers since the motion that the muscle undergoes mainly takes place along the fibers. It follows that such simplified models do not allow evaluation of the heart electro-mechanical function and coupling, which has recently risen as the key point for understanding the LV functionality . In order to thoroughly understand the LV mechanics it is necessary to consider the complete anatomy of the LV given by the orientation of the myocardial fibres in 3D space as described by Torrent Guasp. We propose developing a 3D patient-sensitive model of the LV integrating, for the first time, the ven- tricular band anatomy (fibers orientation), the LV gross anatomy and its functionality. Such model will represent the LV function as a natural consequence of its own ventricular band anatomy. This might be decisive in restoring a proper LV contraction in patients undergoing pace marker treatment. The LV function is defined as soon as the propagation of the contractile electromechanical pulse has been modelled. In our experiments we have used the wave equation for the propagation of the electric pulse. The electromechanical wave moves on the myocardial surface and should have a conductivity tensor oriented along the muscular fibers. Thus, whatever mathematical model for electric pulse propa- gation [4] we consider, the complete anatomy of the LV should be extracted. The LV gross anatomy is obtained by processing multi slice MR images recorded for each patient. Information about the myocardial fibers distribution can only be extracted by Diffusion Tensor Imag- ing (DTI), which can not provide in vivo information for each patient. As a first approach, we have computed an average model of fibers from several DTI studies of canine hearts. This rough anatomy is the input for our electro-mechanical propagation model simulating LV dynamics. The average fiber orientation is updated until the simulated LV motion agrees with the experimental evidence provided by the LV motion observed in tagged MR (TMR) sequences. Experimental LV motion is recovered by applying image processing, differential geometry and interpolation techniques to 2D TMR slices [5]. The pipeline in figure 1 outlines the interaction between simulations and experimental data leading to our patient-tailored model. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Venezia (Italia) | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | B-31470-08 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | IAM | Approved | no | ||
Call Number | IAM @ iam @ GGV2008c | Serial | 1521 | ||
Permanent link to this record | |||||
Author | Debora Gil; Aura Hernandez-Sabate; Mireia Burnat; Steven Jansen; Jordi Martinez-Vilalta | ||||
Title | Structure-Preserving Smoothing of Biomedical Images | Type | Conference Article | ||
Year | 2009 | Publication | 13th International Conference on Computer Analysis of Images and Patterns | Abbreviated Journal | |
Volume | 5702 | Issue | Pages | 427-434 | |
Keywords | non-linear smoothing; differential geometry; anatomical structures segmentation; cardiac magnetic resonance; computerized tomography. | ||||
Abstract | Smoothing of biomedical images should preserve gray-level transitions between adjacent tissues, while restoring contours consistent with anatomical structures. Anisotropic diffusion operators are based on image appearance discontinuities (either local or contextual) and might fail at weak inter-tissue transitions. Meanwhile, the output of block-wise and morphological operations is prone to present a block structure due to the shape and size of the considered pixel neighborhood. In this contribution, we use differential geometry concepts to define a diffusion operator that restricts to image consistent level-sets. In this manner, the final state is a non-uniform intensity image presenting homogeneous inter-tissue transitions along anatomical structures, while smoothing intra-structure texture. Experiments on different types of medical images (magnetic resonance, computerized tomography) illustrate its benefit on a further process (such as segmentation) of images. | ||||
Address | Münster, Germany | ||||
Corporate Author | Thesis | ||||
Publisher | Springer Berlin Heidelberg | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | LNCS | ||
Series Volume | Series Issue | Edition | |||
ISSN | 0302-9743 | ISBN | 978-3-642-03766-5 | Medium | |
Area | Expedition | Conference | CAIP | ||
Notes | IAM | Approved | no | ||
Call Number | IAM @ iam @ GHB2009 | Serial | 1527 | ||
Permanent link to this record | |||||
Author | Debora Gil; Aura Hernandez-Sabate; Mireia Brunat;Steven Jansen; Jordi Martinez-Vilalta | ||||
Title | Structure-preserving smoothing of biomedical images | Type | Journal Article | ||
Year | 2011 | Publication | Pattern Recognition | Abbreviated Journal | PR |
Volume | 44 | Issue | 9 | Pages | 1842-1851 |
Keywords | Non-linear smoothing; Differential geometry; Anatomical structures; segmentation; Cardiac magnetic resonance; Computerized tomography | ||||
Abstract | Smoothing of biomedical images should preserve gray-level transitions between adjacent tissues, while restoring contours consistent with anatomical structures. Anisotropic diffusion operators are based on image appearance discontinuities (either local or contextual) and might fail at weak inter-tissue transitions. Meanwhile, the output of block-wise and morphological operations is prone to present a block structure due to the shape and size of the considered pixel neighborhood. In this contribution, we use differential geometry concepts to define a diffusion operator that restricts to image consistent level-sets. In this manner, the final state is a non-uniform intensity image presenting homogeneous inter-tissue transitions along anatomical structures, while smoothing intra-structure texture. Experiments on different types of medical images (magnetic resonance, computerized tomography) illustrate its benefit on a further process (such as segmentation) of images. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-3203 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | IAM; ADAS | Approved | no | ||
Call Number | IAM @ iam @ GHB2011 | Serial | 1526 | ||
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Author | Debora Gil; Aura Hernandez-Sabate; Oriol Rodriguez; J. Mauri; Petia Radeva | ||||
Title | Statistical Strategy for Anisotropic Adventitia Modelling in IVUS | Type | Journal Article | ||
Year | 2006 | Publication | IEEE Transactions on Medical Imaging | Abbreviated Journal | |
Volume | 25 | Issue | 6 | Pages | 768-778 |
Keywords | Corners; T-junctions; Wavelets | ||||
Abstract | Vessel plaque assessment by analysis of intravascular ultrasound sequences is a useful tool for cardiac disease diagnosis and intervention. Manual detection of luminal (inner) and mediaadventitia (external) vessel borders is the main activity of physicians in the process of lumen narrowing (plaque) quantification. Difficult definition of vessel border descriptors, as well as, shades, artifacts, and blurred signal response due to ultrasound physical properties trouble automated adventitia segmentation. In order to efficiently approach such a complex problem, we propose blending advanced anisotropic filtering operators and statistical classification techniques into a vessel border modelling strategy. Our systematic statistical analysis shows that the reported adventitia detection achieves an accuracy in the range of interobserver variability regardless of plaque nature, vessel geometry, and incomplete vessel borders. Index Terms–-Anisotropic processing, intravascular ultrasound (IVUS), vessel border segmentation, vessel structure classification. | ||||
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ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | IAM;MILAB | Approved | no | ||
Call Number | IAM @ iam @ GHR2006 | Serial | 1525 | ||
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Author | Debora Gil | ||||
Title | Regularized Curvature Flow | Type | Report | ||
Year | 2002 | Publication | CVC Technical Report | Abbreviated Journal | |
Volume | Issue | 63 | Pages | ||
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Publisher | Computer Vision Centre | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
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ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | IAM; | Approved | no | ||
Call Number | IAM @ iam @ Gil2002 | Serial | 1518 | ||
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Author | Debora Gil | ||||
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 | |||
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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. | ||||
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Corporate Author | Thesis | Ph.D. thesis | |||
Publisher | Ediciones Graficas Rey | Place of Publication | Barcelona (Spain) | Editor | Jordi Saludes i Closa;Petia Radeva |
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | 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 | Debora Gil; Petia Radeva | ||||
Title | Curvature based Distance Maps | Type | Report | ||
Year | 2003 | Publication | CVC Technical Report | Abbreviated Journal | |
Volume | Issue | 70 | Pages | ||
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Publisher | Computer Vision Center | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
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Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | IAM;MILAB | Approved | no | ||
Call Number | IAM @ iam @ GIR2003a | Serial | 1534 | ||
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Author | Debora Gil; Petia Radeva | ||||
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. | ||||
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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 | 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 | Debora Gil; Petia Radeva | ||||
Title | Inhibition of False Landmarks | Type | Book Chapter | ||
Year | 2004 | Publication | Recent Advances in Artificial Intelligence Research and Development | Abbreviated Journal | |
Volume | Issue | Pages | 233-244 | ||
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Abstract | We argue that a corner detector should be based on the degree of continuity of the tangent vector to the image level sets, work on the image domain and need no assumptions on neither the image local structure nor the particular geometry of the corner/junction. An operator measuring the degree of differentiability of the projection matrix on the image gradient fulfills the above requirements. Its high sensitivity to changes in vector directions makes it suitable for landmark location in real images prone to need smoothing to reduce the impact of noise. Because using smoothing kernels leads to corner misplacement, we suggest an alternative fake response remover based on the receptive field inhibition of spurious details. The combination of both orientation discontinuity detection and noise inhibition produce our Inhibition Orientation Energy (IOE) landmark locator. | ||||
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Publisher | IOS Press | Place of Publication | Barcelona (Spain) | Editor | al, J.V. et |
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Area | Expedition | Conference | |||
Notes | IAM;MILAB | Approved | no | ||
Call Number | IAM @ iam @ GiR2004a | Serial | 1533 | ||
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