Skip to Main content Skip to Navigation
Theses

Algorithmes d'optimisation de critères pénalisés pour la restauration d'images. Application à la déconvolution de trains d'impulsions en imagerie ultrasonore.

Abstract : The solution to many image restoration and reconstruction problems is often defined as the minimizer of a penalized criterion that accounts simultaneously for the data and the prior. This thesis deals more specifically with the minimization of edge-preserving penalized criteria. We focus on algorithms for large-scale problems. The minimization of penalized criteria can be addressed using a half-quadratic approach (HQ). Converging HQ algorithms have been proposed. However, their numerical cost is generally too high for large-scale problems. An alternative is to implement inexact HQ algorithms. Nonlinear conjugate gradient algorithms can also be considered using scalar HQ algorithms for the line search (NLCG+HQ1D). Some issues on the convergence of the aforementioned algorithms remained open until now. In this thesis we :
- Prove the convergence of inexact HQ algorithms and NLCG+HQ1D.
- Point out strong links between HQ algorithms and NLCG+HQ1D.
- Experimentally show that inexact HQ algorithms and NLCG+HQ1D perform better than exact HQ algorithms, for an image deconvolution test problem.
- Apply the penalized approach to a deconvolution problem in the field of ultrasonic imaging for nondestructive testing.
Complete list of metadatas

Cited literature [122 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00132861
Contributor : Christian Labat <>
Submitted on : Thursday, February 22, 2007 - 5:17:09 PM
Last modification on : Wednesday, December 19, 2018 - 3:02:03 PM
Long-term archiving on: : Wednesday, April 7, 2010 - 12:33:01 AM

Identifiers

  • HAL Id : tel-00132861, version 1

Citation

Christian Labat. Algorithmes d'optimisation de critères pénalisés pour la restauration d'images. Application à la déconvolution de trains d'impulsions en imagerie ultrasonore.. Traitement du signal et de l'image [eess.SP]. Ecole Centrale de Nantes (ECN); Université de Nantes, 2006. Français. ⟨tel-00132861⟩

Share

Metrics

Record views

542

Files downloads

1458