Automated Segmentation of the Walkable Area from Aerial Images for Evacuation Simulation

Computer-aided evacuation simulation is a very import preliminary step when planning safety measures for major public events. We propose a novel, efficient and fast method to extract the walkable area from highresolution aerial images for the purpose of evacuation simulation. In contrast to previous work, where the authors only extracted streets and roads or worked on indoor scenarios, we present an approach to accurately segment the walkable area of large outdoor areas. For this task we use a sophisticated seeded region growing (SRG) algorithm incorporating the information of digital surface models, true-orthophotos and inclination maps calculated from aerial images. Further, we introduce a new annotation and evaluation scheme especially designed for assessing the segmentation quality of evacuation maps. An extensive qualitative and quantitative evaluation, where we study various combinations of SRG methods and parameter settings by the example of different real-world scenarios, shows the feasibility of our approach.