Vanishing Points and Lorries

In this paper, lorries in motorway scenes and their use in vanishing point estimation is studied. Lorries naturally arise in motorway scenes and provide a powerful way to compute three orthogonal vanishing points. Lorries are therefore so interesting, because features, e.g. blob centroid, on usual vehicles do only provide one vanishing point in tra c direction. Also the background of motorway scenes rarely provide edge information in vertical direction. But with three orthogonal vanishing points from a lorry and a square pixel camera with zero skew the calibration matrix can be estimated, the camera pose relative to the lorry can be computed and the real world lengths are known up to a scalar factor. To illustrate the vanishing point estimation, we developed an algorithm to detect corners of cuboid-shaped lorries. This algorithm was formulated as Constraint Satisfaction Problem which has shown to be an e cient and elegant solution. A camera matrix projecting a canonic world cube onto these corners delivers the three orthogonal vanishing points. We showed the applicability of this approach on four test images.