Camera Autocalibration using Predominantly Planar Aerial Imagery

The problem of calibrating an aerial camera without reference points is addressed, with the only assumption that the scenery is nearly planar. We build upon an existing homography-based method taking multiple images of the same planar scene, thereby estimating the camera intrinsics as well as a distortion model. Its satisfactory performance is demonstrated in various scenarios in which sufficient variation of the scene perspective may be achieved. This method breaks down, however, during horizontal flight viewing the underlying terrain. For this scenario, an alternative method is developed based upon generating images from transformed orthoimagery with perspectives in the neighborhood of only one reference image. The satisfactory performance results are presented.