6-DOF camera pose estimation using reference points on an aerial image without altitude information

A new method for estimating a six-degrees-of-freedom camera pose for a ground-view image using reference points on an aerial image is presented. Unlike typical PnP problems, altitude information is not available for the reference points in our case. The camera pose is estimated by minimizing a cost function defined as the sum of squared distances between observed 2D positions of reference points on a ground-view image and corresponding lines that are projections of 3D vertical lines passing through 2D reference points on an aerial image. The accuracy of the proposed method is evaluated quantitatively in both simulation and real environments. The availability of the proposed method is demonstrated by generating AR images from aerial and ground-view images downloaded from Google Maps and Flickr