Planar Motion Estimation and Linear Ground Plane Rectification using an Uncalibrated Generic Camera

Abstract

We address and solve the self-calibration of a generic camera that performs planar motion while viewing (part of) a ground plane. Concretely, assuming initial sets of correspondences between several images of the ground plane as known, we are interested in determining both the camera motion and the geometry of the ground plane. The latter is obtained through the rectification of the image of the ground plane, which gives a bijective correspondence between pixels and points on the ground plane. We initially propose a method to determine the camera motion by using the motion flow between pairs of images. We perform this step with no need of camera calibration. Our solution requires the fixed ground point of the camera motion to be visible on both images. Once the camera motion is known, either by using our method or by other alternative means (e.g. GPS-based), we show that the rectification of the ground plane can be determined linearly from at least three images up to a scale factor. Experimental results on real images are presented at the end of the paper to validate the proposed methods.