Time integration and statistical regulation applied to mobile objects detection in a sequence of images
Description
This PhD thesis deals with the detection of moving objects in monocular image sequences. The first section presents the inherent problems of motion analysis in real applications. We propose a method robust to perturbations frequently encountered during acquisition of outdoor scenes. It appears three main directions for investigations, all of them pointing out the importance of the temporal axis, which is a specific dimension for motion analysis. In the first part, the image sequence is considered as a set of temporal signals. The temporal multi-scale decomposition enables the characterization of various dynamical behaviors of the objects being in the scene at a given instant. A second module integrates motion information. This elementary trajectography of moving objects provides a temporal prediction map, giving a confidence level of motion presence. Interactions between both sets of data are expressed within a statistical regularization. Markov random field models supply a formal framework to convey a priori knowledge of the primitives to be evaluated. A calibration method with qualitative boxes is presented to estimate model parameters. Our approach requires only simple computations and leads to a rather fast algorithm, that we evaluate in the last section over various typical sequences. (author)
Abstract (French)
Cette these traite de la detection d'objets mobiles en imagerie monoculaire. La premiere partie expose la problematique de l'analyse du mouvement dans des applications reelles. Nous proposons une methodologie robuste vis a vis des perturbations frequemment rencontrees lors de l'acquisition de scenes en exterieur. Nous degageons trois directions de recherches qui mettent en relief l'importance de l'axe temporel, dimension privilegiee en analyse du mouvement. Dans une premiere partie, la sequence d'images est assimilee a un faisceau de signaux temporels. La decomposition multi-echelle temporelle mise en oeuvre permet de caracteriser les differents comportements dynamiques presents dans la scene a un instant donne. Un deuxieme module integre l'information de mouvement. Cette trajectographie elementaire des objets mobiles permet d'obtenir une carte de prediction temporelle, donnant un indice de confiance sur la presence d'un mouvement. Les interactions entre ces deux types de donnees sont exprimees au sein d'une regularisation statistique. La modelisation par champs de Markov fournit un cadre formel pour traduire des connaissances a priori sur les primitives a evaluer. Une methode de calibrage par boites qualitatives est presentee pour estimer les parametres de ce modele. Notre approche se ramene a des calculs simples et conduit a une algorithmie relativement rapide, que nous evaluons en derniere partie sur des sequences variees typiques. (auteur)Files
48047041.pdf
Files
(59.5 MB)
| Name | Size | Download all |
|---|---|---|
|
md5:93b4fb4a5e3f22b21b8ac2df0b4bd950
|
59.5 MB | Preview Download |
Additional details
Additional titles
- Original title (French)
- Integration Temporelle et Regularisation Statistique appliquees a la detection d'objets mobiles dans une sequence d'images
Identifiers
Publishing Information
- Imprint Pagination
- 162 p.
- Report number
- FRCEA-TH--8284
INIS
- Country of Publication
- France
- Country of Input or Organization
- France
- INIS RN
- 48047041
- Subject category
- S46: INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; S97: MATHEMATICAL METHODS AND COMPUTING;
- Resource subtype / Literary indicator
- Thesis
- Descriptors DEI
- ALGORITHMS; CALIBRATION; CAMERAS; IMAGE PROCESSING; MARKOV PROCESS; MAXIMUM-LIKELIHOOD FIT; MECHANICAL VIBRATIONS; MOTION DETECTION SYSTEMS; SENSORS; VELOCITY
- Descriptors DEC
- ALARM SYSTEMS; MATHEMATICAL LOGIC; MATHEMATICAL SOLUTIONS; NUMERICAL SOLUTION; PROCESSING; STOCHASTIC PROCESSES
Optional Information
- Notes
- 84 refs.; Available from the INIS Liaison Officer for France, see the 'INIS contacts' section of the INIS website for current contact and E-mail addresses: http://www.iaea.org/inis/Contacts/