Monocular Egomotion Estimation based on Image Matching

In this paper, we propose a novel method for computing the egomotion of a monocular camera mounted on a vehicle based on the matching of distant regions in consecutive frames. Our approach takes advantage of the fact that the image projection of a plane can provide information about the camera motion. Instead of tracking points between frames, we track distant regions in the scene because they behave as an infinity plane. As a consequence of tracking this infinity plane, we obtain an image geometric transformation (more precisely, an infinity homography) relating two consecutive frames. This transformation is actually capturing the camera rotation, since the effect produced by the translation can be neglected at long distances. Then, we can compute the camera rotation as the result of the previously estimated infinity homography. After that, rotation can be canceled from images, just leading to a translation explaining the motion between two frames. Experiments on real image sequences show that our approach reaches higher accuracy w.r.t. state-of-the-art methods.