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

Retinal images are often degraded with a blur that varies across the gield 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 identification of valid local PSFs and perform interpolation to obtain the space-variant PSF. The method was tested on artificial and real degraded retinal images. Results show significant improvement in the visibility of subtle details like small blood vessels. © 2013 SPIE.

• Fecha de publicación: 2013
• Institución: Universidad Tecnológica de Bolívar
• Repositorio: Repositorio Institucional UTB
• Idioma: eng
• OAI Identifier: oai:repositorio.utb.edu.co:20.500.12585/9069
• Acceso en línea: https://hdl.handle.net/20.500.12585/9069
• Palabra clave: Deblurring; Deconvolution; Medical image; Retinal image; Space-variant restoration; Blind estimations; Blind restoration; Deblurring; Deblurring algorithms; Linear Interpolation; Point-spread functions; Retinal image; Space variants; Blood vessels; Deconvolution; Medical imaging; Ophthalmology; Optics; Restoration; Image enhancement
• Rights: restrictedAccess
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/