Automatic correction of perspective and optical distortions

摘要

Perspective and optical (lens) distortions are aberrations of very different nature that can simultaneously affect an image. Perspective distortion is caused by the position of the camera, especially when it is too close to the scene. Optical distortion is a lens aberration which causes straight lines in the scene to be projected onto the image as distorted lines. Standard methods to correct perspective distortion are based on the estimation of the vanishing points, which can fail if lens distortion is significant. In this paper, we introduce a new method which addresses both problems in a single framework. First we estimate a lens distortion model by extracting a collection of distorted lines in the image. These distorted lines are afterward rectified by means of the lens distortion model and used to estimate the vanishing points. Finally, the vanishing points are used to correct the perspective distortion. We present a variety of experiments to show the reliability of the proposed method.