DIRECT GEOREFERENCING APPROACHES FOR CLOSE-RANGE AND UAV PHOTOGRAMMETRY IN THE BUILT HERITAGE DOMAIN

Abstract. Direct georeferencing uses onboard sensors to measure the position and orientation of camera during image acquisition for photogrammetric applications. This approach aims eliminate use traditional Ground Control Points (GCPs) in process order reduce costs time survey operations. The direct technique involves integrating measurements from inertial measurement units (IMUs) Global Navigation Satellite Systems (GNSS) data evaluate attitude with high accuracy (a few centimeters). In Built Heritage domain, this is mainly followed by employment UAVs (Uncrewed aerial systems) platforms that are nowadays equipped highly accurate systems able external parameters process. For terrestrial applications, already achieved tests were performed; moreover, today available extracting information close-range limited sometimes under development. To possibility offered these new tools, a test on 3D ImageVector (REDcatch GmbH) has been performed. results strategies will be presented analyzed understand better potentiality promising approach.