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Fernando Vilariño, & Enric Marti. (2008). New didactic techniques in the EHES applying mobile technologies.
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H. Chouaib, Oriol Ramos Terrades, Salvatore Tabbone, F. Cloppet, & N. Vincent. (2008). Feature Selection Combining Genetic Algorithm and Adaboost Classifiers. In 19th International Conference on Pattern Recognition (pp. 1–4).
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T.O. Nguyen, Salvatore Tabbone, & Oriol Ramos Terrades. (2008). Symbol Descriptor Based on Shape Context and Vector Model of Information Retrieval. In Proceedings of the 8th IAPR International Workshop on Document Analysis Systems, (pp. 191–197).
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H. Chouaib, Salvatore Tabbone, Oriol Ramos Terrades, F. Cloppet, N. Vincent, & A.T. Thierry Paquet. (2008). Sélection de Caractéristiques à partir d'un algorithme génétique et d'une combinaison de classifieurs Adaboost. In Colloque International Francophone sur l'Ecrit et le Document (pp. 181–186).
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T.O. Nguyen, Salvatore Tabbone, Oriol Ramos Terrades, & A.T. Thierry. (2008). Proposition d'un descripteur de formes et du modèle vectoriel pour la recherche de symboles. In Colloque International Francophone sur l'Ecrit et le Document (pp. 79–84).
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Salvatore Tabbone, Oriol Ramos Terrades, & S. Barrat. (2008). Histogram of radon transform. A useful descriptor for shape retrieval. In 19th International Conference on Pattern Recognition (pp. 1–4).
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Sergio Escalera. (2008). Coding and Decoding Design of ECOCs for Multi-class Pattern and Object Recognition A (Petia Radeva, & Oriol Pujol, Eds.). Ph.D. thesis, Ediciones Graficas Rey, .
Abstract: Many real problems require multi-class decisions. In the Pattern Recognition field,
many techniques have been proposed to deal with the binary problem. However,
the extension of many 2-class classifiers to the multi-class case is a hard task. In
this sense, Error-Correcting Output Codes (ECOC) demonstrated to be a powerful
tool to combine any number of binary classifiers to model multi-class problems. But
there are still many open issues about the capabilities of the ECOC framework. In
this thesis, the two main stages of an ECOC design are analyzed: the coding and
the decoding steps. We present different problem-dependent designs. These designs
take advantage of the knowledge of the problem domain to minimize the number
of classifiers, obtaining a high classification performance. On the other hand, we
analyze the ECOC codification in order to define new decoding rules that take full
benefit from the information provided at the coding step. Moreover, as a successful
classification requires a rich feature set, new feature detection/extraction techniques
are presented and evaluated on the new ECOC designs. The evaluation of the new
methodology is performed on different real and synthetic data sets: UCI Machine
Learning Repository, handwriting symbols, traffic signs from a Mobile Mapping System, Intravascular Ultrasound images, Caltech Repository data set or Chaga’s disease
data set. The results of this thesis show that significant performance improvements
are obtained on both traditional coding and decoding ECOC designs when the new
coding and decoding rules are taken into account.
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Rozenn Dhayot, Fernando Vilariño, & Gerard Lacey. (2008). Improving the Quality of Color Colonoscopy Videos. EURASIP JIVP - EURASIP Journal on Image and Video Processing, 139429(1), 1–9.
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Bogdan Raducanu, & Jordi Vitria. (2008). Face Recognition by Artificial Vision Systems: A Cognitive Perspective. IJPRAI - International Journal of Pattern Recognition and Artificial Intelligence, 899–913.
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Francisco Javier Orozco, Xavier Roca, & Jordi Gonzalez. (2008). Real-Time Gaze Tracking with Appearance-Based Models. MVAP - Machine Vision Applications, 20(6), 353–364.
Abstract: Psychological evidence has emphasized the importance of eye gaze analysis in human computer interaction and emotion interpretation. To this end, current image analysis algorithms take into consideration eye-lid and iris motion detection using colour information and edge detectors. However, eye movement is fast and and hence difficult to use to obtain a precise and robust tracking. Instead, our
method proposed to describe eyelid and iris movements as continuous variables using appearance-based tracking. This approach combines the strengths of adaptive appearance models, optimization methods and backtracking techniques.Thus,
in the proposed method textures are learned on-line from near frontal images and illumination changes, occlusions and fast movements are managed. The method achieves real-time performance by combining two appearance-based trackers to a
backtracking algorithm for eyelid estimation and another for iris estimation. These contributions represent a significant advance towards a reliable gaze motion description for HCI and expression analysis, where the strength of complementary
methodologies are combined to avoid using high quality images, colour information, texture training, camera settings and other time-consuming processes.
Keywords: Keywords Eyelid and iris tracking, Appearance models, Blinking, Iris saccade, Real-time gaze tracking
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Oriol Pujol, Sergio Escalera, & Petia Radeva. (2008). An Incremental Node Embedding Technique for Error Correcting Output Codes. PR - Pattern Recognition, 713–725.
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Bogdan Raducanu, & Jordi Vitria. (2008). Learning to Learn: From Smarts Machines to Intelligent Machines. PRL - Patter Recognition Letters, 1024–1032.
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Angel Sappa, Fadi Dornaika, Daniel Ponsa, David Geronimo, & Antonio Lopez. (2008). An Efficient Approach to Onboard Stereo Vision System Pose Estimation. TITS - IEEE Transactions on Intelligent Transportation Systems, 9(3), 476–490.
Abstract: This paper presents an efficient technique for estimating the pose of an onboard stereo vision system relative to the environment’s dominant surface area, which is supposed to be the road surface. Unlike previous approaches, it can be used either for urban or highway scenarios since it is not based on a specific visual traffic feature extraction but on 3-D raw data points. The whole process is performed in the Euclidean space and consists of two stages. Initially, a compact 2-D representation of the original 3-D data points is computed. Then, a RANdom SAmple Consensus (RANSAC) based least-squares approach is used to fit a plane to the road. Fast RANSAC fitting is obtained by selecting points according to a probability function that takes into account the density of points at a given depth. Finally, stereo camera height and pitch angle are computed related to the fitted road plane. The proposed technique is intended to be used in driverassistance systems for applications such as vehicle or pedestrian detection. Experimental results on urban environments, which are the most challenging scenarios (i.e., flat/uphill/downhill driving, speed bumps, and car’s accelerations), are presented. These results are validated with manually annotated ground truth. Additionally, comparisons with previous works are presented to show the improvements in the central processing unit processing time, as well as in the accuracy of the obtained results.
Keywords: Camera extrinsic parameter estimation, ground plane estimation, onboard stereo vision system
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E. Provenzi, Carlo Gatta, M. Fierro, & A. Rizzi. (2008). A Spatially Variant White-Patch and Gray-World Method for Color Image Enhancement Driven by Local Constant. TPAMI - IEEE Transactions on Pattern Analysis and Machine Intelligence, 1757–1770.
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David Vazquez, & Antonio Lopez. (2008). Intrusion Classification in Intelligent Video Surveillance Systems.
Abstract: An intelligent video surveillance system (IVS) is a camera-based installation able to process in real-time the images coming from the cameras. The aim is to automatically warn about different events of interest at the moment they happen. Daview system of Davantis is a com mercial example of IVS system. The problems addressed by any IVS system, and so Daview, are so challenging that none IVS system is perfect, thus, they need continuous improvement. Accordingly, this project aims to study different approaches in order to outperform current Daview performance, in particular, we bet for improving its classification core. We present an in deep study of the state of the art on IVS systems, as well as on how Daview works. Based on that knowledge, we propose four possibilities for improving Daview classification capabilities: improve existent classifiers; improve existing classifiers combination; create new classifiers and create new classifier-based architectures. Our main contribution has been the incorporation of state-of-the-art feature selection and machine learning techniques for the classification tasks, a viewpoint not fully addressed in current Daview system. After a comprehensive quantitative evaluation we will see how one of our proposals clearly outperforms the overall performance of current Daview system. In particular the classification core that we finally propose consists in an AdaBoost One-Against-All architecture that uses appearance and motion features that were already present in current Daview system
Keywords: Human detection; Car detection; Intrusion detection
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