Master thesis “Spatial data acquisition with unmanned aerial system and evaluation of photogrammetric point cloud classification quality” provides an overview of the field of unmanned aerial systems for spatial data acquisition, theory of data processing and possibilities of automatic photogrammetric point cloud classification with quality evaluation. We define unmanned aerial systems for spatial data acquisition, their characteristic and describe necessary subsystems. We briefly describe the legal basis and the airspace of the Republic of Slovenia. We describe unmanned aerial system senseFly eBee, which was also used to carry out practical work and PostFlight Terra 3D, software for data processing. We define typical workflow for spatial data acquisition with unamend aerial systems. The theoretical part is comprised of the detailed description of the methods and procedures used for data processing and automatic point cloud classification. We describe methods for 3D reconstruction and orientation from images with the procedure Structure from Motion, bundle block adjustment, self-calibration. We describe one of the methods for densifying point cloud and review some methods for automatic classification. In the context of practical research we carried out a project with unamend aerial system. The practical work included survey flight planning, carrying out survey flight and processing of the data. Three main products were created: dense point cloud, digital elevation model and orthomosaic. Photogrammetric unmanned aerial systems may in some aspects replace aerial laser scanning, so we carried out a comparison between photogrammetric point cloud and laser scanning point cloud. The main goal of the practical part of the thesis was to test automatic classification of the photogrammetric point cloud. We performed many classification with different software’s, with different input parameters and evaluate quality of different methods according to ground truth data.
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