Blind restoration of retinal images degraded by space-variant blur with adaptive blur estimation

0422848 - ÚTIA 2014 RIV US eng C - Conference Paper (international conference)
Marrugo, A. - Millán, M. S. - Šorel, Michal - Šroubek, Filip
Blind restoration of retinal images degraded by space-variant blur with adaptive blur estimation.
Proceedings ot the 8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications. Bellingham: SPIE, 2013, 8785D1 - 1-8785D1 - 8. ISBN 978-0-8194-9601-0. ISSN 0277-786X.
[8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications. Porto (PT), 22.07.2013-26.07.2013]
R&D Projects: GA ČR GA13-29225S
Institutional support: RVO:67985556
Keywords : medical image * retinal image * deconvolution * deblurring * space-variant restoration
Subject RIV: JD - Computer Applications, Robotics
http://library.utia.cas.cz/separaty/2014/ZOI/sorel-0422848.pdf

Retinal images are often degraded with a blur that varies across the eld view. Because traditional deblurring algorithms assume the blur to be space-invariant they typically fail in the presence of space-variant blur. In this work we consider the blur to be both unknown and space-variant. To carry out the restoration, we assume that in small regions the space-variant blur can be approximated by a space-invariant point-spread function (PSF). However, instead of deblurring the image on a per-patch basis, we extend individual PSFs by linear interpolation and perform a global restoration. Because the blind estimation of local PSFs may fail we propose a strategy for the identication of valid local PSFs and perform interpolation to obtain the space-variant PSF. The method was tested on articial and real degraded retinal images. Results show signicant improvement in the visibility of subtle details like small blood vessels.
Permanent Link: http://hdl.handle.net/11104/0230915