Parametric Model of the Perspective Projection of a Road with Applications to Lane Keeping and 3D Road Reconstruction

This paper describes an algorithm for the computation of the 3D structure of a road and of the motion state of an in-vehicle CCD camera from the lane borders on the image plane. A parametric model of the projective projection of the lane borders on the image plane is introduced and a fast and reliable algorithm to compute its parameters is described. The physical significance of the model is demonstrated by showing that the model parameters completely determine the position of the vehicle inside the lane, its heading direction, and the local structure of the road. The conditions of applicability of the model are also given and the results of its application to a sequence of images taken during a test run discussed. The algorithm is suited to real time applications and indeed an implementation on the dedicated hardware of the mobile laboratory MOBLAB runs at a frame rate of 12 images per second.