1. Ph.D. Student, Institute of Geodesy and Photogrammetry, Dept. of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich 8093, Switzerland (corresponding author).
2. Professor, Institute of Geodesy and Photogrammetry, Dept. of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich 8093, Switzerland.
3. Ph.D. Student, Institute of Geodesy and Photogrammetry, Dept. of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich 8093, Switzerland.
4. Research Assistant, Institute of Geodesy and Photogrammetry, Dept. of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich 8093, Switzerland.