The small, cost-effective design and the simple control of modern unmanned aerial vehicles drive the use and further development of this steadily. To be able to carry out useful activities, the aircraft must be able to determine its own position as well as its surroundings quickly and accurately. In this dissertation, the development of methods for automatic positioning and environment measurement by means of cameras shall be promoted. A novel combination of camera position determination, 3D reconstruction and mapping will be developed to perform this task reliably and quickly. With the help of such a system, the autonomous use of UAVs is possible whereby a variety of applications can be realized.