Tesis doctoral de Daniel Ponsa Mussarra
This thesis focuses the analysis of video sequences, applying model-based techniques for extracting quantitative information. In particular, we make several proposals in two application areas: shape tracking based on contour models, and detection and tracking of vehicles in images acquired by a camera installed on a mobile platform. the work devoted to shape tracking follows the paradigm of active contours, from which we present a review of the existent approaches. First, we measure the performance of the most common algorithms (kalman based filters and particle filters), and then we evaluate its implementation aspects trough an extensive experimental study, where several synthetic sequences are considered, distorted with different degrees of noise. Thus, we determine the best way to implement in practice these classical tracking algorithms, and we identify its benefits and drawbacks. next, the work is oriented towards the improvement of contour tracking algorithms based on particle filters. These algorithms reach good results provided that the number of particles is high enough, but unfortunately the required number of particles grows exponentially with the number of parameters to be estimated. Therefore, and in the context of contour tracking, we present three variants of the classical particle filter, corresponding to three new strategies to deal with this problem. First, we propose to improve the contour tracking by propagating more accurately the particles from one image to the next one. This is done by using a linear approximation of the optimal propagation function. The second proposed strategy is based in estimating part of the parameters analytically. Thus, we aim to do a more productive use of the particles, reducing the amount of model parameters that must be estimated through them. The third proposed method aims to exploit the fact that, in contour tracking applications, the parameters related to the rigid transform can be estimated accurately enough i
Datos académicos de la tesis doctoral «Model-based visual localisation of contours and vehicles«
- Título de la tesis: Model-based visual localisation of contours and vehicles
- Autor: Daniel Ponsa Mussarra
- Universidad: Autónoma de barcelona
- Fecha de lectura de la tesis: 29/06/2007
Dirección y tribunal
- Director de la tesis
- Antonio Manuel López Peña
- Tribunal
- Presidente del tribunal: Juan jose Villanueva pipaón
- thorsten Graf (vocal)
- Juan Andrade cetto (vocal)
- georg Schneider (vocal)