Geometry and Image Quality Assessment of SkySat Imagery for Building Identification

Due to improved ground resolution, optical space imagery is increasingly being used instead of aerial images for mapping purposes. The classic large-format space images today achieve a ground resolution of 0.3m with very good geometry. However, they are expensive for smaller projects. There is now an alternative with nano-satellites ranging in size from 1U to 3U $(\mathbf{1}\mathbf{U}\ =\mathbf{10}\mathbf{cm}\times \mathbf{10}\mathbf{cm}\times \mathbf{10}\mathbf{cm})$ up to micro-satellites with approximately $\mathbf{30}\mathbf{cm}\times \mathbf{30}\mathbf{cm}\times \mathbf{55}\mathbf{cm}$. 1U optical satellites are now available in large numbers, but their ground resolution is limited to 3m to 5m. With the SkySat micro-satellites, images are now available down to a ground resolution of 0.5m. The geometry and the effective ground resolution of the SkySat image products as well as their potential for identifying buildings were examined. This paper is limited to optical satellites available for civil use. The research was carried out for a project to update buildings in a topographic map.