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Basic Research | Applied Research (Projects) | Open Positions for PhD Students

Basic Research:

Title
Classification of visual data in high dimensional spaces
Members:

Dr. Jordi Vitrià, Marco Bressan, David Guillamet, David Masip.

 
Description:
High dimensional data appears in many pattern recognition problems such as remote sensing, appearance-based object recognition, text categorization, etc. A stochastic approach for the classification of high dimensional data is always a delicate issue. For linear or quadratic classifiers the number of training samples depends linearly or quadratically on the data dimensionality subset of features, an exhaustive sequential feature selection procedure is required, so the size of the problem grows combinatorially on the dimension. Furthermore, the training sample size needs to increase exponentially in order to effectively estimate the multivariate densities needed to perform nonparametric classification. To avoid the problem of dimensionality, the most common approach is the implementation of feature extraction or dimensionality reduction algorithms. Our approach does not seek dimensionality reduction followed by the implementation of parametric or nonparametric techniques for density estimation. Instead, it focuses on the higher level statistical properties of the data (independent component analysis, non negative matrix factorization), which is transformed in such a way that density estimation in the transformed space is simplified and more accurate. We are also working on the use of Naïve Bayes Classifier under this approach.
Keywords: Independent Component Analysis, Non-negative Matrix Factorization, Naïve Bayes Classifier.
Literature: M.Bressan, D.Guillamet, J.Vitrià. Using an ICA Representation of Local Color Histograms for Object Recognition. Pattern Recognition (accepted for publication). April 2002.
M.Bressan, D.Guillamet, J.Vitrià. Multiclass Object Recognition using Class-Conditional Independent Component Analysis. Submitted for publication to Cybernetics and Systems. March 2002.
M.Bressan, J.Vitrià. Independent Feature Selection. Submitted for publication to IEEE Trans on PAMI. December 2001.

Applied Research (Projects):

Contact:

Dr. Jordi Vitrià
Computer Vision Center
Edifici O, Campus Universitat Autònoma de Barcelona
08129 Bellaterra (Barcelona) Spain
Phone: +34 93 581 18 28
E-mail:
jordi@cvc.uab.es

 
Description:
CorkInspect is an IST EU project within the EUTIST-IMV cluster. Corkinspect is a Trial project intending to support, as a major objective, the early customisation and validation of a Computer Vision solution for cork stopper production control. The main discriminant feature of CorkInspect is its innovative development based on its way of building inspection and control rules. CorkInspect establishes its control rules through an iterative procedure based on statistical control features and boundaries tolerances from selected samples. That brings great flexibility and, in special, when we work with natural products, this flexibility to establish control features becomes a must.
Time Frame: January 2002-March 2003
Literature: Petia Radeva(CVC) , Marco Bressan(CVC), Antonio Tobar(CVC) and Jordi Vitrià(CVC). Real Time Inspection of Cork Stoppers using Parametric Methods in High Dimensional Spaces. IASTED International Conference, Signal and Image Processing (SIP 2002), August 12-14, 2002, USA.
David Guillamet (CVC), Jordi Vitria(CVC). Determining a Suitable Metric When using Non-negative Matrix Factorization David Guillamet (CVC), Jordi Vitria(CVC). International Conference on Pattern Recognition (IAPR 2002), August 11-15 2002 - Québec City Convention Center.
Augmented Reality and Ambient Intelligence
Contact:

Dr. Jordi Vitrià
Computer Vision Center
Edifici O, Campus Universitat Autònoma de Barcelona
08129 Bellaterra (Barcelona) Spain
Phone: +34 93 581 18 28
E-mail:
jordi@cvc.uab.es

 
Description:

The perception of reality can be enhanced making connections between physical and virtual world. Computer vision is a candidate to implement this connection.

Example I: Visual Tags. Paper is a technology that will continue to be the ideal choice for certain activities. Emphasis has to be put on the development of technologies which attemp to better integrate this paper use with coexisting digital technologies.

Example II: Information in Places. What if we could put information in places? More precisely, what if we could associate information with a place or an object and perceive the information as if it were really there?

Ambient Intelligence builds on three recent key technologies (Ubiquitous Computing, Ubiquitous Communication and Intelligent User Interfaces) for developing the next generation of Information Processing systems. Under this paradigm, people will be surrounded by intelligent and intuitive interfaces embedded in everyday objects around us and an environment recognizing and responding to the presence of individuals in an invisible way. Our environment must be aware of human presence, personalities, needs and must be capable of responding intelligently to spoken or gestured indications of desire, and even in engaging in intelligent dialogue. Visual perception of objects and events will play an important role in this development.

Time Frame: January 2002-March 2003
Literature:

Intelligent Imaging Environment for Mobile Applications/ Entorno Inteligente para Imágenes en Aplicaciones Móviles
(web)
Contact:

Dr. Jordi Vitrià
Computer Vision Center
Edifici O, Campus Universitat Autònoma de Barcelona
08129 Bellaterra (Barcelona) Spain
Phone: +34 93 581 18 28
E-mail:
jordi@cvc.uab.es

 
Description:

El desarrollo de sistemas de comunicación inalámbrica, distribuidos, y el incremento en la autonomía de los ordenadores móviles (hand-held computers, subnotebooks) nos permiten el acceso a los recursos computacionales de una organización en una gama creciente de contextos. Estos cambios tecnológicos obligan a una reformulación importante de varios de los conceptos usados hasta el momento en entornos computacionales clásicos, como son las interfaces persona-máquina, la movilidad, la interactividad, la usabiliad y la portabilidad.

Time Frame: January 2001-March 2003
Literature:

The following positions are currently available for a PhD:

Face Recognition and Analysis for Context Aware Environments.
Published:
Position:
25.6.2002
PhD Thesis
Contact:

Dr. Jordi Vitrià
Computer Vision Center
Edifici O, Campus Universitat Autònoma de Barcelona
08129 Bellaterra (Barcelona) Spain
P
hone: +34 93 581 21 69
E-mail:jordi@cvc.uab.es

Description:

Ambient Intelligence builds on three recent key technologies (Ubiquitous Computing, Ubiquitous Communication and Intelligent User Interfaces) for developing the next generation of Information Processing systems. Under this paradigm, people will be surrounded by intelligent and intuitive interfaces embedded in everyday objects around us and an environment recognizing and responding to the presence of individuals in an invisible way. Our environment must be aware of human presence, personalities, needs and must be capable of responding intelligently to spoken or gestured indications of desire, and even in engaging in intelligent dialogue. Visual perception of people and events will play an important role in this development. This PhD thesis will focus on the development of real time face analysis system and its use on contex aware environments.

Time Frame: Beginning in January 2003
Literature: D.Guillamet, B.Schiele,J.Vitrià. Analyzing Non-Negative Matrix Factorization for Image Classification. Accepted to ICPR 2002.
D.Guillamet, J.Vitrià. Non-negative matrix factorization to extract part-based representations. Butlletí de l'ACIA, n.25, 2001, pp. 255-262.
A.Pujol, J.Vitrià, F.Lumbreras, J.J.Villanueva. Topological principal component analysis for face encoding and recognition. Pattern Recognition Letters, pp. 769-776, Volume 22, Issue 6-7, May 2001.

M.Bressan, D.Guillamet, J.Vitrià. Independent Feature Selection. Submitted for publication to IEEE Trans on PAMI. December 2001.
Requirements: We are looking for a highly motivated student with strong interest in computer vision and pattern recognition, especially in the areas of classification and Bayesian analysis. Solid mathematical and programming skills are also required.