Geometry reconstruction of urban scenes by tracking vertical edges

Obtaining 3D geometric and texture information of urban scenes has received a great deal of attention in many fields such as civil engineering, traffic systems, car navigation systems, entertainment etc. It is, however, difficult to obtain a 3D description of an outdoor static scene because a camera is easily influenced by the environment such as lighting and background. In addition, it is expensive to obtain the description, especially in data input by human hand. To resolve these problems, we need an efficient and automatic framework for 3D modeling of city scenes. We propose an efficient method with epipolar-plane image analysis to model a 3D city scene along a road from an image sequence recorded by a camera boarded on a vehicle. With the method presented, we detect vertical edges and track the edges in a spatiotemporal solid of images. The locus of the edges gives us the distances from the path of the camera to the objects including the edges, such as buildings as well as their heights. The side of an object will be estimated as a rectangle, of which both sides are two different estimated edges with the same height. Our method is able to obtain both the distance and the height of the objects simultaneously. Therefore, the constructed model is expected to be stable and precise.