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Incremental Mosaicking of Images from Autonomous, Small-Scale UAVs

Unmanned aerial vehicles (UAVs) have been recently deployedin various civilian applications such as environmentalmonitoring, aerial imaging or surveillance. Small-scaleUAVs are of special interest for first responders since theycan rather easily provide bird’s eye view images of disasterareas. In this paper we present a hybrid approach to mosaickan overview image of the area of interest given a setof individual images captured by UAVs flying at low altitude.Our approach combines metadata-based and imagebasedstitching methods in order to overcome the challengesof low-altitude, small-scale UAV deployment such as nonnadirview, inaccurate sensor data, non-planar ground surfacesand limited computing and communication resources.For the generation of the overview image we preserve georeferencingas much as possible, since this is an importantrequirement for disaster management applications. Ourmosaicking method has been implemented on our UAV systemand evaluated based on a quality metric.