Located in the heart of Europe, Saxony is characterised by an impressive heritage that encompasses tens of thousands of archaeological sites and registered monuments, bearing testimony to the cultural and historical importance of the region, both within Germany and Central Europe. The effective protection and management of this valuable but finite resource requires innovative new technologies with a focus on accuracy, efficiency and intuitive design. The project "Archaeocopter" (www.archaeocopter.de) is committed to the design and development of ultralight unmanned aerial vehicles (UAV) for airborne image data acquisition in archaeology and related fields.
The acquisition of high-resolution, georeferenced imagery is a fundamental prerequisite for the detection and documentation of archaeological heritage. Structure from Motion (SfM) is a popular and robust method for producing 3D reconstructions from series of overlapping images (multi-view reconstruction). It provides heritage professionals with a flexible and low-cost method for the documentation and digital preservation of objects of interest, especially complex architectural remains. SfM currently suffers from two fundamental limitations that restrict the degree to which the quality of the resulting models can be assured: the approach is computationally demanding, and the reconstructed point clouds tend to be inhomogeneous. However, the video material produced by UAV-borne cameras contains massively overlapping image data and therefore constitutes ideal input material for the SfMbased reconstruction of buildings, sites or entire landscapes. In addition, parallel processing of data allows the rapid production of preview models useful for quality assurance.