Method, software product, and system for determining a position and orientation in a 3D reconstruction of the earth's surface

A system for determining a position and an orientation, the system (500) comprising a set of sensors (510), a processor (520) and a data storage (550), wherein the data storage (550) and the set of sensors (510) are connected to the processor (520), wherein the set of sensors (510) comprises a set of cameras (511) arranged to capture a plurality of images of Earth's surface and comprises an inertial navigation system (INS) and/or an inertial measurement unit (IMU) (512) arranged to determine changes in position and orientation of the system (500), wherein the set of sensors (510) is arranged to provide sensor data (210) comprising said plurality of images and corresponding navigation data indicative of changes in position and orientation to the processor (520), wherein the memory storage (550) is arranged to provide source data (260) for at least some of Earth's surface to the processor (520), wherein the source data (260) comprises a source DSM (270) indicative of the height of Earth's surface and a corresponding orthophoto (280) of Earth's surface, wherein the processor (520) is arranged to

• obtain sensor data (210) from the set of sensors (510);
• form a 3D reconstruction (220) of a part of Earth's surface based on obtained sensor data (210);
• obtain source data (260) corresponding to a region comprising at least said part of Earth's surface from the data storage (550), wherein said source data (260) comprises a corresponding source digital surface model, DSM, (270) and the corresponding orthophoto (280) in a predetermined coordinate system;
• determine a sensor DSM (230) and a sensor texture (240) based on the formed 3D reconstruction (220);
• match the sensor DSM (230) and the sensor texture (240) with the source DSM (270) and the orthophoto (280), wherein matching comprises finding a position and an orientation of the sensor DSM (230) and the sensor texture (240) in the source DSM (270) and the orthophoto (280);
• and
• determine a position and an orientation of the 3D reconstruction (220) in said predetermined coordinate system of the source data (260) based on said matching.