Constructing 3D city models by merging ground-based and airborne views

In this paper, we present a fast approach to automated generation of textured 3D city models with both high details at ground level, and complete coverage for bird´s-eye view. A close-range facade model is acquired at the ground level by driving a vehicle equipped with laser scanners and a digital camera under normal traffic conditions on public roads; a far-range Digital Surface Map (DSM), containing complementary roof and terrain shape, is created from airborne laser scans, then triangulated, and finally texture mapped with aerial imagery. The facade models are first registered with respect to the DSM by using Monte-Carlo-Localization, and then merged with the DSM by removing redundant parts and filling gaps. The developed algorithms are evaluated on a data set acquired in downtown Berkeley.