Pose determination and plane measurement using a trapezium

In this paper, a new affine invariant of trapezia is introduced, and the projection of trapezia is deduced from this invariant. Known the lengths of the two parallel sides of a trapezium, pose estimation and plane measurement can be realized in a very simple way from the projection of the trapezium. Experiments on simulated and real images show that the approach is robust and accurate. Two parallel lines, which can determine a trapezium, are not rare in many structured scenes, the proposed method has wide applicability.