Earthquake-collapsed building extraction from LiDAR and aerophotograph based on OBIA

Estimation of damages caused by a large earthquake is a major task in the post disaster mitigation process. To enhance the relief and rescue operation in the affected area it is required to receive rapid, accurate knowledge about the conditions of damaged area. Remote sensing techniques were proved to be useful to detect, identify and monitor the impact and effect of natural disasters in last decades. Recently emerging LiDAR data provide the height of the ground objects, which can be used for extracting the collapsed buildings in a complex urban environment. Using the aerophotographs and the normalized digital surface model (nDSM) extracted from LiDAR data, a method based on OBIA and SVM was developed to extract the earthquake-collapsed building. The test study in Haiti's capital, Port-au-Prince after 2010 Jan. 12 earthquake shows that the method can extract collapsed buildings with high accuracy.