| dc.description.abstract | Three-dimensional building models can be reconstructed using data generated by a variety of remote sensing techniques, such as satellite, UAV, aerial survey, LiDAR point clouds, etc. Each method has advantages and disadvantages for the reconstruction of 3D building models. In recent years, the spatial resolution of satellite imagery has gradually improved, reaching tens of centimeters (cm) level, resulting in the use of satellite imagery to reconstruct 3D building models has gradually been discussed. Although there is still a gap between the spatial resolution of satellite imagery and aerial imagery or LiDAR point cloud data, satellite imagery has a wide coverage and high temporal resolution, so there are still certain advantages for reconstructing 3D building models.
This research focuses on image analysis based on high resolution optical satellite imagery and 3D building models reconstruction with an accuracy of the OGC CityGML LOD1 level. Deep learning technique is applied in this study to automatically extract building footprints from satellite images and remove excess areas that are too small or not buildings. Next, Minimum Bounding Rectangle (MBR), regularization and generalization processing are utilized to shape the more regular and square building polygons. Finally, the Digital Surface Model (DSM) is incorporated to extract sub-structures on the upper floor of each building, and the elevation data is used to fit the height of each polygon with the RANSAC (RANdom SAmple Consensus) algorithm to reconstruct block-based 3D building models.
After various corrections and the removal of outliers, the plane (X, Y) error and the elevation (Z) error of 3D building models can reach 4.044 m and 1.517 m respectively. Since the spatial resolution of satellite imagery is not enough to generate complex roof models, the roofs of reconstructed 3D building models is flat roofs, and the accuracy conforms to the OGC CityGML LOD1 specification. Subsequent 3D building models can be applied to a great deal of purposes, such as urban planning, land monitoring, disaster reconstruction, 3D building simulation, etc., providing a variety of 3D applications closer to the real world. | en_US |