Modification of SfM Algorithm Referring to Image Topology and Its Application in 3-Dimension Reconstruction of Disaster Area

The rapid and accurate large scene 3Dreconstruction technique from multi-view images canprovide important and reliable information for emergency response and disaster assessment.Againstthe low efficiency of Structure from Motion(SfM)algorithm,this paper develops an image Topologybased Structure from Motion(TSfM)algorithm referring to image topological conjunction.Genera-ting the image topological conjunction with the flight-control data acquired by unmanned aerial vehiclesystem(UAV),the searching range for matched images is reduced in the process of feature matching,and the time complexity of TSfM algorithm in the feature matching stage decreases from O(n2)toO(n)as compared with SfM algorithm.The experimental results show that TSfM algorithm makes itpossible for rapid large scene 3Dreconstruction with sequence images from UAV.Furthermore,it isreached that the relative error of the 3Dscene model reconstructed by TSfM algorithm is comparablewith that by SfM algorithm.The proposed TSfM algorithm is applied for Lushan earthquake disaster3Dreconstruction with UAV images,which can help to detect the seismic-induced landslides withmore information.