An Interactive Scheme for Building Modeling Using the Split-merge-shape Algorithm

The most important feature in urban modeling is the 3D building model. It is essential in many applications, such as 3D GIS, cyber city, true-orthophoto generation, etc. Due to the huge demand of 3D building model, an effective solution for geometrical building modeling is required. In this paper, a 3D building modeling based on the Split-Merge-Shape (SMS) algorithm is presented. Since the SMS algorithm adapts 3D visible roof-edges for building modeling, a semi-automatic scheme for measuring 3D visible roof-edges from multi-view aerial images is proposed. In the SMS algorithm, the SPLIT and MERGE steps are the procedures for topology reconstruction from isolated roof-edges. The SHAPE step uses the available roof-edge height information to define an appropriate rooftop. With the SMS method, the topographic mapping of buildings, and geometric building modeling, can be seamlessly integrated into a unified procedure. In the paper, we will start with an overview of state-of-the-art technologies on the subject of building modeling. The SMS algorithm is then presented and integrated with the proposed semi-automatic scheme for 3D roof-edges measurement. A preliminary test utilizing a set of four 1:5,000 aerial images is demonstrated. Experimental results indicate that high reliability and accuracy may be reached with limited manual efforts.