Séminaire ETIS : Matthieu Guerquin-Kern
Titre du séminaire et orateur
Wavelet-Based Reconstruction for Magnetic Resonance Imaging.
Matthieu Guerquin-Kern, Ecole Polytechnique Fédérale de Lausanne & ENSEA Cergy.
Date et lieu
Mardi 11 septembre 2012, 11h.
Université de Cergy-Pontoise, St-Martin 1, salle 562, bât. A, 5ème étage.
We present our work on magnetic resonance imaging that focuses on the development of reconstruction algorithms that are faster and simpler than state-of-the-art solutions, while preserving their quality.
First, we briefly present the physical principles that underlie the acquisition of MRI data and motivate the classical model and reconstruction algorithms. Next, we propose novel simulation tools for the validation of reconstruction methods. To honor the continuous nature of the underlying physics, we suggest the use of analytical phantoms. Our results show that the inverse-crime situation impairs significantly the assessment of the performance of reconstruction methods, particularly, the non-linear ones.
Finally, we investigate the design of algorithms that achieve reconstruction with a sparsity constraint expressed in a wavelet domain. We develop a practical method that combines the advantages of speed and quality. Applied on challenging reconstruction problems, with simulated and in-vivo data, we significantly reduce the reconstruction time over state-of-the-art techniques without compromising quality.
N.B. : la thèse de Matthieu Guerquin-Kern est accessible en ligne à cette adresse.