Underwater Scene Recovery Using Wavelength-Dependent Refraction of Light

This paper proposes a method of underwater depth estimation from an orthographic multispectral image. In accordance with Snell's law, incoming light is refracted when it enters the water surface, and its directions are determined by the refractive index and the normals of the water surface. The refractive index is wavelength-dependent, and this leads to some disparity between images taken at different wavelengths. Given the camera orientation and the refractive index of a medium such as water, our approach can reconstruct the underwater scene with unknown water surface from the disparity observed in images taken at different wavelengths. We verified the effectiveness of our method through simulations and real experiments on various scenes.