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Author Sergio Escalera; David M.J. Tax; Oriol Pujol; Petia Radeva; Robert P.W. Duin
Title Subclass Problem-Dependent Design for Error-Correcting Output Codes Type Journal
Year 2008 Publication IEEE Trans. on Pattern Analysis and Machine Intelligence, vol.30(6):1041–1054 Abbreviated Journal
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Area Expedition Conference
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ ETP2008 Serial 951
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Author Sergio Escalera; Oriol Pujol; Petia Radeva
Title Detection of Complex Salient Regions Type Journal
Year 2008 Publication EURASIP Journal on Advances in Signal Processing, vol. 2008, article ID451389, 11 pages Abbreviated Journal
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Area Expedition Conference
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPR2008b Serial 960
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Author Sergio Escalera; Oriol Pujol; Petia Radeva
Title Sub-Class Error-Correcting Output Codes Type Book Chapter
Year 2008 Publication Computer Vision Systems. 6th International Conference Abbreviated Journal
Volume 5008 Issue Pages 494–504
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Abstract
Address Santorini (Greece)
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 ICVS
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPR2008c Serial 963
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Author Sergio Escalera; Oriol Pujol; Petia Radeva
Title Loss-Weighted Decoding for Error-Correcting Output Coding Type Conference Article
Year 2008 Publication 3rd International Conference on Computer Vision Theory and Applications, Abbreviated Journal
Volume 2 Issue Pages 117–122
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Abstract
Address Madeira (Portugal)
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 VISAPP
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPR2008a Serial 964
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Author O. Rodriguez-Leor; Carlo Gatta; E Fernandez-Nofrerias; Oriol Pujol; Neus Salvatella; C. Bosch; H. Tizon; Petia Radeva; J. Mauri
Title Computationally Efficient Image-based IVUS Pullbacks Gating Type Journal
Year 2008 Publication European Heart Journal, ESC Supplement, Munich, 2008, p. 775 Abbreviated Journal
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Abstract
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Area Expedition Conference
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ RGF2008 Serial 1036
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Author Carlo Gatta; Oriol Pujol; O. Rodriguez-Leor; J. Mauri; Petia Radeva
Title Robust Image-based IVUS Pullbacks Gating Type Book Chapter
Year 2008 Publication Proceedings 11th International ConferenceMedical Image Computing and Computer–Assisted Intervention Abbreviated Journal
Volume 5242 Issue Pages 518–525
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Abstract
Address NY (USA)
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title LNCS
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference MICCAI
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ GPR2008a Serial 1037
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Author Carlo Gatta; Oriol Pujol; O. Rodriguez-Leor; Josefina Mauri; Petia Radeva
Title Improved Rigid Registration of Vessel Structures using the Fast Radial Symmetry Transform Type Conference Article
Year 2008 Publication Computer Vision for Intravascular Imaging CVII’08 Workshop Medical Image Computing and Computer–Assisted Intervention , 11th International Conference Abbreviated Journal
Volume Issue Pages 128–136
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Abstract
Address NY (USA)
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 MICCAI
Notes (down) MILAB;HUPBA Approved no
Call Number BCNPCL @ bcnpcl @ GPR2008b Serial 1038
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Author Sergio Escalera; Oriol Pujol; J. Mauri; Petia Radeva
Title IVUS Tissue Characterization with Sub-class Error-correcting Output Codes Type Conference Article
Year 2008 Publication Computer Vision and Pattern Recognition Workshops, 2008. CVPR Workshops 2008. IEEE Computer Society Conference on, pp. 1–8, 23–28 juny 2008. Abbreviated Journal
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Abstract Intravascular ultrasound (IVUS) represents a powerful imaging technique to explore coronary vessels and to study their morphology and histologic properties. In this paper, we characterize different tissues based on Radio Frequency, texture-based, slope-based, and combined features. To deal with the classification of multiple tissues, we require the use of robust multi-class learning techniques. In this context, we propose a strategy to model multi-class classification tasks using sub-classes information in the ECOC framework. The new strategy splits the classes into different subsets according to the applied base classifier. Complex IVUS data sets containing overlapping data are learnt by splitting the original set of classes into sub-classes, and embedding the binary problems in a problem-dependent ECOC design. The method automatically characterizes different tissues, showing performance improvements over the state-of-the-art ECOC techniques for different base classifiers and feature sets.
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 CVPR
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPM2008 Serial 1041
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Author Sergio Escalera; Oriol Pujol; Petia Radeva
Title Separability of Ternary Codes for Sparse Designs of Error-Correcting Output Codes Type Journal Article
Year 2009 Publication Pattern Recognition Letters Abbreviated Journal PRL
Volume 30 Issue 3 Pages 285–297
Keywords
Abstract Error Correcting Output Codes (ECOC) represent a successful framework to deal with multi-class categorization problems based on combining binary classifiers. In this paper, we present a new formulation of the ternary ECOC distance and the error-correcting capabilities in the ternary ECOC framework. Based on the new measure, we stress on how to design coding matrices preventing codification ambiguity and propose a new Sparse Random coding matrix with ternary distance maximization. The results on the UCI Repository and in a real speed traffic categorization problem show that when the coding design satisfies the new ternary measures, significant performance improvement is obtained independently of the decoding strategy applied.
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 (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPR2009a Serial 1153
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Author Francesco Ciompi; Oriol Pujol; O. Rodriguez-Leor; Carlo Gatta; Angel Serrano; Petia Radeva
Title Enhancing In-Vitro IVUS Data for Tissue Characterization Type Conference Article
Year 2009 Publication 4th Iberian Conference on Pattern Recognition and Image Analysis Abbreviated Journal
Volume 5524 Issue Pages 241–248
Keywords
Abstract Intravascular Ultrasound (IVUS) data validation is usually performed by comparing post-mortem (in-vitro) IVUS data and corresponding histological analysis of the tissue, obtaining a reliable ground truth. The main drawback of this method is the few number of available study cases due to the complex procedure of histological analysis. In this work we propose a novel semi-supervised approach to enhance the in-vitro training set by including examples from in-vivo coronary plaques data set. For this purpose, a Sequential Floating Forward Selection method is applied on in-vivo data and plaque characterization performances are evaluated by Leave-One-Patient-Out cross-validation technique. Supervised data inclusion improves global classification accuracy from 89.39% to 91.82%.
Address Póvoa de Varzim, Portugal
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 978-3-642-02171-8 Medium
Area Expedition Conference IbPRIA
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ CPR2009a Serial 1162
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Author Sergio Escalera; Eloi Puertas; Petia Radeva; Oriol Pujol
Title Multimodal laughter recognition in video conversations Type Conference Article
Year 2009 Publication 2nd IEEE Workshop on CVPR for Human communicative Behavior analysis Abbreviated Journal
Volume Issue Pages 110–115
Keywords
Abstract Laughter detection is an important area of interest in the Affective Computing and Human-computer Interaction fields. In this paper, we propose a multi-modal methodology based on the fusion of audio and visual cues to deal with the laughter recognition problem in face-to-face conversations. The audio features are extracted from the spectogram and the video features are obtained estimating the mouth movement degree and using a smile and laughter classifier. Finally, the multi-modal cues are included in a sequential classifier. Results over videos from the public discussion blog of the New York Times show that both types of features perform better when considered together by the classifier. Moreover, the sequential methodology shows to significantly outperform the results obtained by an Adaboost classifier.
Address Miami (USA)
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 2160-7508 ISBN 978-1-4244-3994-2 Medium
Area Expedition Conference CVPR
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPR2009c Serial 1188
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Author Sergio Escalera; Oriol Pujol; Petia Radeva
Title Recoding Error-Correcting Output Codes Type Conference Article
Year 2009 Publication 8th International Workshop of Multiple Classifier Systems Abbreviated Journal
Volume 5519 Issue Pages 11–21
Keywords
Abstract One of the most widely applied techniques to deal with multi- class categorization problems is the pairwise voting procedure. Recently, this classical approach has been embedded in the Error-Correcting Output Codes framework (ECOC). This framework is based on a coding step, where a set of binary problems are learnt and coded in a matrix, and a decoding step, where a new sample is tested and classified according to a comparison with the positions of the coded matrix. In this paper, we present a novel approach to redefine without retraining, in a problem-dependent way, the one-versus-one coding matrix so that the new coded information increases the generalization capability of the system. Moreover, the final classification can be tuned with the inclusion of a weighting matrix in the decoding step. The approach has been validated over several UCI Machine Learning repository data sets and two real multi-class problems: traffic sign and face categorization. The results show that performance improvements are obtained when comparing the new approach to one of the best ECOC designs (one-versus-one). Furthermore, the novel methodology obtains at least the same performance than the one-versus-one ECOC design.
Address Reykjavik (Iceland)
Corporate Author Thesis
Publisher Springer Berlin Heidelberg Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0302-9743 ISBN 978-3-642-02325-5 Medium
Area Expedition Conference MCS
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ EPR2009d Serial 1190
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Author Francesco Ciompi; Oriol Pujol; O. Rodriguez-Leor; Angel Serrano; J. Mauri; Petia Radeva
Title On in-vitro and in-vivo IVUS data fusion Type Conference Article
Year 2009 Publication 12th International Conference of the Catalan Association for Artificial Intelligence Abbreviated Journal
Volume 202 Issue Pages 147-156
Keywords
Abstract The design and the validation of an automatic plaque characterization technique based on Intravascular Ultrasound (IVUS) usually requires a data ground-truth. The histological analysis of post-mortem coronary arteries is commonly assumed as the state-of-the-art process for the extraction of a reliable data-set of atherosclerotic plaques. Unfortunately, the amount of data provided by this technique is usually few, due to the difficulties in collecting post-mortem cases and phenomena of tissue spoiling during histological analysis. In this paper we tackle the process of fusing in-vivo and in-vitro IVUS data starting with the analysis of recently proposed approaches for the creation of an enhanced IVUS data-set; furthermore, we propose a new approach, named pLDS, based on semi-supervised learning with a data selection criterion. The enhanced data-set obtained by each one of the analyzed approaches is used to train a classifier for tissue characterization purposes. Finally, the discriminative power of each classifier is quantitatively assessed and compared by classifying a data-set of validated in-vitro IVUS data.
Address Cardona (Spain)
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 978-1-60750-061-2 Medium
Area Expedition Conference CCIA
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ CPR2009d Serial 1204
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Author Pierluigi Casale; Oriol Pujol; Petia Radeva
Title Face-to-face social activity detection using data collected with a wearable device Type Conference Article
Year 2009 Publication 4th Iberian Conference on Pattern Recognition and Image Analysis Abbreviated Journal
Volume 5524 Issue Pages 56–63
Keywords
Abstract In this work the feasibility of building a socially aware badge that learns from user activities is explored. A wearable multisensor device has been prototyped for collecting data about user movements and photos of the environment where the user acts. Using motion data, speaking and other activities have been classified. Images have been analysed in order to complement motion data and help for the detection of social behaviours. A face detector and an activity classifier are both used for detecting if users have a social activity in the time they worn the device. Good results encourage the improvement of the system at both hardware and software level
Address Póvoa de Varzim, Portugal
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 978-3-642-02171-8 Medium
Area Expedition Conference IbPRIA
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ CPR2009b Serial 1206
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Author Francesco Ciompi; Oriol Pujol; E Fernandez-Nofrerias; J. Mauri; Petia Radeva
Title ECOC Random Fields for Lumen Segmentation in Radial Artery IVUS Sequences Type Conference Article
Year 2009 Publication 12th International Conference on Medical Image and Computer Assisted Intervention Abbreviated Journal
Volume 5762 Issue II Pages
Keywords
Abstract The measure of lumen volume on radial arteries can be used to evaluate the vessel response to different vasodilators. In this paper, we present a framework for automatic lumen segmentation in longitudinal cut images of radial artery from Intravascular ultrasound sequences. The segmentation is tackled as a classification problem where the contextual information is exploited by means of Conditional Random Fields (CRFs). A multi-class classification framework is proposed, and inference is achieved by combining binary CRFs according to the Error-Correcting-Output-Code technique. The results are validated against manually segmented sequences. Finally, the method is compared with other state-of-the-art classifiers.
Address London, UK
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 978-3-642-04270-6 Medium
Area Expedition Conference MICCAI
Notes (down) MILAB;HuPBA Approved no
Call Number BCNPCL @ bcnpcl @ CPF2009 Serial 1228
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