3.2.4. Software and Hardware Requirements

UAS data has been processed with the commercially available software Pix4D (www.pix4d.com) which refers to a well-established professional photogrammetric software. Next to commercially available software, freely available software for UAS image processing, such as Open Drone Map (www.opendronemap.org), offer viable alternatives. Open Drone Map follows a structure-from-motion pipeline which is based on Open SFM. Whereas previous open source software most often had the deficiency to not provide an intuitive, user-friendly user interface, Open Drone Map can be used as a command line tool, with a live USB or via a user-friendly Web-based graphical user interface. Recommended system requirements are similar for Pix4D and Open Drone Map, and refer to 16GB RAM for small projects over with 100–500 images, 32 GB RAM for projects over 500 images and 64 GB RAM for very large projects with over 2000 images. The photogrammetric processing in this paper was completed with Pix4D and took several hours for the Gahanga and Busogo dataset and more than a day for the Muhoza dataset.
