Closed form solution for the scale ambiguity problem in monocular visual odometry

This paper presents a fast monocular visual odometry algorithm. We propose a closed form solution for the computation of the unknown scale ratio between two consecutive image pairs. Our method requires only 1 2D-3D correspondence. A least square solution can also be found in closed form when more correspondences are available. Additionally we provide a first order analysis on the propagation of the error from the noise in the image features to the computation of the scale. We show by means of simulated and real data that our method is more robust and accurate than standard techniques. We demonstrate that our visual odometry algorithm is well suited for the task of 3D reconstruction in urban areas.