Semiautomatic registration between ground-level panoramas and an orthorectified aerial image for building modeling

Aerial imagery and ground-level imagery are two complementary data sources for architectural modeling. How to integrate them is a critical issue in creating complete, photo-realistic and large-scale urban models. We describe a semiautomatic approach of detecting feature correspondences between ground-level images and the building footprint in an orthorectified aerial image. The ground-level images are stitched into panoramas in order to obtain a wide camera field of view. Line segments are extracted from ground-level images. Their corresponding segments on the building footprints are automatically detected through a voting process. Meanwhile the camera pose of the ground-level images is also obtained. Wrong correspondences are corrected through user interaction. Later, the height values of the building roof corners are computed and a piece-wise planar 3D model with photo-realistic facade and roof texture is then created.