Advanced visualization polarimetric imaging: Removal of water spray effect utilizing circular polarization

Abstract

Circular polarization (CP) memory is a well-known phenomenon whereby natural light becomes partially circularly polarized after scattering by water spray several times, and the circularly polarized state can be well preserved within a certain propagation distance. In this study, a CP imaging method combined with the multi-scale analysis in the frequency domain is proposed to enhance the vision in rainy conditions. The images were first decomposed into multi-scales. CP characteristics of light were employed in the low-frequency parts to improve the quality of images in rainy conditions, and the high-frequency parts compensated specific structure information. Experimental results demonstrate that the proposed method can remove the water spray effect thereby improving the vision of degraded rainy-day images.