Ability to image underwater is highly desired for scientific and military applications, including optical communications, submarine awareness, diver visibility, and mine detection. Underwater imaging is severely impaired by scattering and optical turbulence associated with refraction index fluctuations. This work introduces novel approach to restoration of degraded underwater imagery based on multi-frame correction technique developed for atmospheric distortions. The method represents synthesis of "lucky-region" fusion and optical flow based image warping. Developed multi-frame image restoration algorithm is applied to sets of images collected in laboratory under controlled conditions as well as field test data. Reliance of image restoration on sophistication of the optical flow algorithm is shown. Variable degrees of image degradation mitigation which manifest themselves as high spatial frequency content recovery are demonstrated depending on imaging conditions and ratio of typical image spatial frequency scale to typical degradation spatial frequency scale.

Date Published: 28 September 2011
PDF: 8 pages
Proc. SPIE 8185, Electro-Optical and Infrared Systems: Technology and Applications VIII, 81850O (28 September 2011); doi: 10.1117/12.898914

Published in SPIE Proceedings Vol. 8185:
Electro-Optical and Infrared Systems: Technology and Applications VIII
David A. Huckridge; Reinhard R. Ebert, Editor(s)