Reconstruction with underwater stereo vision

Abstract

Conventional multi-view theory fails to explain underwater stereo vision because of the refraction bends light rays. This paper focuses on one of the most common scenarios of underwater vision, a stereo vision system of two cameras with a flat housing, in which the light ray refracts twice, once at the air-housing interface, and once at the housing-water interface.The papermodelsthe geometry of the light propagation explicitly. Under the principle of light ray's reversibility,discussion on one camera's view in 2D follows the backward projection by casting a light ray from the camera center to the object point.After the entire light ray's coplanarity is proved, the 2D case extends to 3D space easily. In 3D case, computation of object point from the casted ray is derived from the stereo view model. An 3D reconstruction algorithm is also proposed. The algorithm is concise and feasible because no particular configuration or additional device is required. It is proved accurate and low error rate in the experiment.