Defocus deblurring for catadioptric omnidirectional imaging based on coded aperture and omni-total variation

• Published in: Advanced robotics Vol. 29; no. 16; pp. 1031 - 1043
• Main Authors: Li, Yongle, Lou, Jingtao, Xu, Youchun
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 18-08-2015
• Subjects: Apertures; catadioptric omnidirectional imaging; coded aperture; defocus blur; image restoration; Imaging; Mathematical analysis; omni-total variation; optimal focused plane; Optimization; Point spread functions; Stitching; Strategy
• ISSN: 0169-1864; 1568-5535
• DOI: 10.1080/01691864.2015.1033460

The problem of catadioptric omnidirectional imaging defocus blur, which is caused by lens aperture and mirror curvature, becomes more severe when high-resolution sensors and large apertures are applied. In order to overcome this problem, a novel method based on coded aperture technique is proposed in this article. Firstly, the defocus blur of catadioptric omnidirectional imaging is analyzed to calculate the point spread function for different scene points. Then, a method of obtaining optimal focused plane is proposed. Lastly, based on the strategies of neighboring annuluses division and stitching of omnidirectional images, a deconvolution algorithm using omni-total variation prior is applied to obtain all-focused/sharp omnidirectional images. Experimental results demonstrate that the proposed method is effective for omnidirectional image defocus deblurring and can be applied to most existing catadioptric omnidirectional imaging systems.