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	Author	Aura Hernandez-Sabate; Debora Gil; Petia Radeva; E.N.Nofrerias
	Title	Anisotropic processing of image structures for adventitia detection in intravascular ultrasound images			Type	Conference Article
	Year	2004	Publication	Proc. Computers in Cardiology	Abbreviated Journal
	Volume	31	Issue		Pages	229-232
	Keywords
	Abstract	The adventitia layer appears as a weak edge in IVUS images with a non-uniform grey level, which difficulties its detection. In order to enhance edges, we apply an anisotropic filter that homogenizes the grey level along the image significant structures (ridges, valleys and edges). A standard edge detector applied to the filtered image yields a set of candidate points prone to be unconnected. The final model is obtained by interpolating the former line segments along the tangent direction to the level curves of the filtered image with an anisotropic contour closing technique based on functional extension principles
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Chicago (USA)	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; MILAB			Approved	no
	Call Number	IAM @ iam @ HGR2004			Serial	1555
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	Author	Petia Radeva; Joan Serrat; Enric Marti
	Title	A snake for model-based segmentation			Type	Conference Article
	Year	1995	Publication	Proc. Conf. Fifth Int Computer Vision	Abbreviated Journal
	Volume		Issue		Pages	816-821
	Keywords	snakes; elastic matching; model-based segmenta tion
	Abstract	Despite the promising results of numerous applications, the hitherto proposed snake techniques share some common problems: snake attraction by spurious edge points, snake degeneration (shrinking and attening), convergence and stability of the deformation process, snake initialization and local determination of the parameters of elasticity. We argue here that these problems can be solved only when all the snake aspects are considered. The snakes proposed here implement a new potential eld and external force in order to provide a deformation convergence, attraction by both near and far edges as well as snake behaviour selective according to the edge orientation. Furthermore, we conclude that in the case of model-based seg mentation, the internal force should include structural information about the expected snake shape. Experiments using this kind of snakes for segmenting bones in complex hand radiographs show a signicant improvement.
	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		Medium
	Area		Expedition		Conference
	Notes	MILAB;ADAS;IAM			Approved	no
	Call Number	IAM @ iam @ RSM1995			Serial	1634
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	Author	Aura Hernandez-Sabate; Debora Gil; Albert Teis
	Title	How Do Conservation Laws Define a Motion Suppression Score in In-Vivo Ivus Sequences?			Type	Conference Article
	Year	2007	Publication	Proc. IEEE Ultrasonics Symp	Abbreviated Journal
	Volume		Issue		Pages	2231-2234
	Keywords	validation standards; IVUS motion compensation; conservation laws.
	Abstract	Evaluation of arterial tissue biomechanics for diagnosis and treatment of cardiovascular diseases is an active research field in the biomedical imaging processing area. IntraVascular UltraSound (IVUS) is a unique tool for such assessment since it reflects tissue morphology and deformation. A proper quantification and visualization of both properties is hindered by vessel structures misalignments introduced by cardiac dynamics. This has encouraged development of IVUS motion compensation techniques. However, there is a lack of an objective evaluation of motion reduction ensuring a reliable clinical application This work reports a novel score, the Conservation of Density Rate (CDR), for validation of motion compensation in in-vivo pullbacks. Synthetic experiments validate the proposed score as measure of motion parameters accuracy; while results in in vivo pullbacks show its reliability in clinical cases.
	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		Medium
	Area		Expedition		Conference
	Notes	IAM			Approved	no
	Call Number	IAM @ iam @ HTG2007			Serial	1550
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	Author	Aura Hernandez-Sabate; David Rotger; Debora Gil
	Title	Image-based ECG sampling of IVUS sequences			Type	Conference Article
	Year	2008	Publication	Proc. IEEE Ultrasonics Symp. IUS 2008	Abbreviated Journal
	Volume		Issue		Pages	1330-1333
	Keywords	Longitudinal Motion; Image-based ECG-gating; Fourier analysis
	Abstract	Longitudinal motion artifacts in IntraVascular UltraSound (IVUS) sequences hinders a properly 3D reconstruction and vessel measurements. Most of current techniques base on the ECG signal to obtain a gated pullback without the longitudinal artifact by using a specific hardware or the ECG signal itself. The potential of IVUS images processing for phase retrieval still remains little explored. In this paper, we present a fast forward image-based algorithm to approach ECG sampling. Inspired on the fact that maximum and minimum lumen areas are related to end-systole and end-diastole, our cardiac phase retrieval is based on the analysis of tissue density of mass along the sequence. The comparison between automatic and manual phase retrieval (0.07 ± 0.07 mm. of error) encourages a deep validation contrasting with ECG signals.
	Address	Beijing (China)
	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		Medium
	Area		Expedition		Conference
	Notes	IAM;MILAB			Approved	no
	Call Number	IAM @ iam @ HRG2008			Serial	1553
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	Author	V. Valev; Petia Radeva
	Title	Structural Pattern Recognition by Non-Reducible Descriptors			Type	Conference Article
	Year	1994	Publication	Proc. International Workshop on Syntactic and Structural Pattern Recognition.	Abbreviated Journal
	Volume		Issue		Pages
	Keywords
	Abstract
	Address	Nahariya, Israel
	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		Medium
	Area		Expedition		Conference
	Notes	MILAB			Approved	no
	Call Number	BCNPCL @ bcnpcl @ VaR1994			Serial	107
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	Author	V. Valev; Petia Radeva
	Title	A Method of Solving Pattern or image Recognition Problems by Learning Boolean Formulas.			Type	Miscellaneous
	Year	1992	Publication	Proc. of 11th IAPR International Conference on Pattern Recognition, Hague, Netherlands, IEEE Computer Society Press, vol. II, pp. 359–362.	Abbreviated Journal
	Volume		Issue		Pages
	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		Medium
	Area		Expedition		Conference
	Notes	MILAB			Approved	no
	Call Number	BCNPCL @ bcnpcl @ VaR1992b			Serial	253
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	Author	Aura Hernandez-Sabate; Petia Radeva; Antonio Tovar; Debora Gil
	Title	Vessel structures alignment by spectral analysis of ivus sequences			Type	Conference Article
	Year	2006	Publication	Proc. of CVII, MICCAI Workshop	Abbreviated Journal
	Volume		Issue		Pages	39-36
	Keywords
	Abstract	Three-dimensional intravascular ultrasound (IVUS) allows to visualize and obtain volumetric measurements of coronary lesions through an exploration of the cross sections and longitudinal views of arteries. However, the visualization and subsequent morpho-geometric measurements in IVUS longitudinal cuts are subject to distortion caused by periodic image/vessel motion around the IVUS catheter. Usually, to overcome the image motion artifact ECG-gating and image-gated approaches are proposed, leading to slowing the pullback acquisition or disregarding part of IVUS data. In this paper, we argue that the image motion is due to 3-D vessel geometry as well as cardiac dynamics, and propose a dynamic model based on the tracking of an elliptical vessel approximation to recover the rigid transformation and align IVUS images without loosing any IVUS data. We report an extensive validation with synthetic simulated data and in vivo IVUS sequences of 30 patients achieving an average reduction of the image artifact of 97% in synthetic data and 79% in real-data. Our study shows that IVUS alignment improves longitudinal analysis of the IVUS data and is a necessary step towards accurate reconstruction and volumetric measurements of 3-D IVUS.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Copenhaguen (Denmark),	Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title	1st International Wokshop on Computer Vision for Intravascular and Intracardiac Imaging (CVII’06)	Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes	IAM; MILAB			Approved	no
	Call Number	IAM @ iam @ HRT2006			Serial	1552
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	Author	J. Weickert; Bart M. Ter Haar Romeny; Antonio Lopez; W. Van Enk
	Title	Orientation Analysis by Coherence-Enhancing Diffusion.			Type	Miscellaneous
	Year	1997	Publication	Proc. of the Real World Computing Symposium.	Abbreviated Journal
	Volume		Issue		Pages
	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		Medium
	Area		Expedition		Conference
	Notes	ADAS			Approved	no
	Call Number	ADAS @ adas @ WTL1997			Serial	211
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	Author	Ernest Valveny; Enric Marti
	Title	Learning of structural descriptions of graphic symbols using deformable template matching			Type	Conference Article
	Year	2001	Publication	Proc. Sixth Int Document Analysis and Recognition Conf	Abbreviated Journal
	Volume		Issue		Pages	455-459
	Keywords
	Abstract	Accurate symbol recognition in graphic documents needs an accurate representation of the symbols to be recognized. If structural approaches are used for recognition, symbols have to be described in terms of their shape, using structural relationships among extracted features. Unlike statistical pattern recognition, in structural methods, symbols are usually manually defined from expertise knowledge, and not automatically infered from sample images. In this work we explain one approach to learn from examples a representative structural description of a symbol, thus providing better information about shape variability. The description of a symbol is based on a probabilistic model. It consists of a set of lines described by the mean and the variance of line parameters, respectively providing information about the model of the symbol, and its shape variability. The representation of each image in the sample set as a set of lines is achieved using deformable template matching.
	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		Medium
	Area		Expedition		Conference
	Notes	DAG;IAM;			Approved	no
	Call Number	IAM @ iam @ VMA2001			Serial	1654
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	Author	Robert Benavente; Laura Igual; Fernando Vilariño
	Title	Current Challenges in Computer Vision			Type	Book Whole
	Year	2008	Publication	Proccedings of the Third Internal Workshop	Abbreviated Journal
	Volume		Issue		Pages
	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	978-84-936529-0-6	Medium
	Area		Expedition		Conference	CVCRD
	Notes	MILAB;CIC;SIAI			Approved	no
	Call Number	BCNPCL @ bcnpcl @ BIV2008			Serial	1110
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	Author	Maria Vanrell; Felipe Lumbreras; A. Pujol; Ramon Baldrich; Josep Llados; Juan J. Villanueva
	Title	Colour Normalisation Based on Background Information.			Type	Miscellaneous
	Year	2001	Publication	Proceeding ICIP 2001, IEEE International Conference on Image Processing	Abbreviated Journal	ICIP 2001
	Volume		Issue	1	Pages	874–877
	Keywords
	Abstract
	Address	Grecia.
	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		Medium
	Area		Expedition		Conference
	Notes	ADAS;DAG;CIC			Approved	no
	Call Number	ADAS @ adas @ VLP2001			Serial	167
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	Author	Jose Luis Alba; A. Pujol; Juan J. Villanueva
	Title	Separating Geometry from Texture to Improve Face Analysis.			Type	Miscellaneous
	Year	2001	Publication	Proceeding ICIP 2001, IEEE International Conference on Image Processing, 2:673–676	Abbreviated Journal
	Volume		Issue		Pages
	Keywords
	Abstract
	Address	Grecia
	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		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	ISE @ ise @ APV2001c			Serial	71
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	Author	Aura Hernandez-Sabate; Debora Gil; Josefina Mauri; Petia Radeva
	Title	Reducing cardiac motion in IVUS sequences			Type	Conference Article
	Year	2006	Publication	Proceeding of Computers in Cardiology	Abbreviated Journal
	Volume	33	Issue		Pages	685-688
	Keywords
	Abstract	Cardiac vessel displacement is a main artifact in IVUS sequences. It hinders visualization of the main structures in an appropriate orientation and alignment and affects extracting vessel measurements. In this paper, we present a novel approach for image sequence alignment based on spectral analysis, which removes rigid dynamics, preserving at the same time the vessel geometry. First, we suppress the translation by taking, for each frame, the center of mass of the image as origin of coordinates. In polar coordinates with such point as origin, the rotation appears as a horizontal displacement. The translation induces a phase shift in the Fourier coefficients of two consecutive polar images. We estimate the phase by adjusting a regression plane to the phases of the principal frequencies. Experiments show that the presented strategy suppress cardiac motion regardless of the acquisition device. 1.
	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		Medium
	Area		Expedition		Conference
	Notes	IAM; MILAB			Approved	no
	Call Number	IAM @ iam @ HGM2006a			Serial	1554
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	Author	Joel Barajas; Jaume Garcia; Francesc Carreras; Sandra Pujades; Petia Radeva
	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	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	Aura Hernandez-Sabate; Debora Gil; Petia Radeva
	Title	On the usefulness of supervised learning for vessel border detection in IntraVascular Imaging			Type	Conference Article
	Year	2005	Publication	Proceeding of the 2005 conference on Artificial Intelligence Research and Development	Abbreviated Journal
	Volume		Issue		Pages	67-74
	Keywords	classification; vessel border modelling; IVUS
	Abstract	IntraVascular UltraSound (IVUS) imaging is a useful tool in diagnosis of cardiac diseases since sequences completely show the morphology of coronary vessels. Vessel borders detection, especially the external adventitia layer, plays a central role in morphological measures and, thus, their segmentation feeds development of medical imaging techniques. Deterministic approaches fail to yield optimal results due to the large amount of IVUS artifacts and vessel borders descriptors. We propose using classification techniques to learn the set of descriptors and parameters that best detect vessel borders. Statistical hypothesis test on the error between automated detections and manually traced borders by 4 experts show that our detections keep within inter-observer variability.
	Address
	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		Medium
	Area		Expedition		Conference
	Notes	IAM;MILAB			Approved	no
	Call Number	IAM @ iam @ HGR2005c			Serial	1549
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