Comparison of Digital Maps Created by Stereo Plotting and Vectorization Based on Images Acquired by Unmanned Aerial Vehicle

Abstract

Unmanned aerial vehicles (UAVs) are becoming an economical and efficient means to create digital maps, but until now, the vectorization method has been used to extract topographic features from orthoimages for large-scale mapping. The aim of this study is to determine the potential of UAV photogrammetry for digital mapping with stereo plotting, which can include vertical position information. In this study, the entire work process of UAV photogrammetry was performed using a case study in Korea, where 314 images were acquired with a BirdsEyeView Aerobotics FireFly6 PRO. To compare the results, digital maps were created by stereo plotting and vectorization. To evaluate the accuracy of the digital maps created by stereo plotting, we evaluated the accuracy of the aerial triangulation (AT) work from ground control points (GCPs) and the position accuracy of the maps from checkpoints (CPs). The accuracy of the AT work was on the sub-centimeter order and the position accuracy of the maps was on the sub-decimeter order. We also compared a digital map produced by the Korean National Geographic Information Institute (NGII) with the maps created by stereo plotting and vectorization to evaluate the mapping accuracy. From the results of the comparison, we found that the maps created by stereo plotting were more accurate than those created by vectorization.