We present an approach to easily remove the effects of haze from passively acquired images. It is based on the fact that usually the natural illuminating light scattered by atmospheric particles (airlight) is partially polarized. Optical filtering alone cannot remove the haze effects, except in restricted situations. Our method, however, is based on physics-based analysis that works under a wide range of atmospheric and viewing conditions, even if the polarization is low. The approach does not rely on specific scattering models such as Rayleigh scattering, and does not rely on the knowledge of illumination directions. It can be used with as few as two images taken through a polarizer at different orientations [image] [image]. This method works instantly, without relying on changes of weather conditions [image].

As a by-product, the method yields a range map of the scene [image], that enables scene rendering as if imaged from different viewpoints. It also yields information about the atmospheric particles. We present experimental results of complete dehazing of outdoor scenes, in far from ideal conditions for polarization filtering. We obtain a great improvement of scene contrast and correction of color.

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