Projected Time Travel: Architectural Heritage Projection in Situ

Abstract: Aside of architectural heritage that is readily visible to the public like well-known tourist sites, there are many heritage objects which only exist in restricted excavation sites or in museums to where they have been moved. Some of them exist in literature only. Archaeologists put a lot of effort into the reconstruction of architectural heritage, even in digital form. Still, most of this work is hardly ever shown to the public in its original size. We advocate the public visibility of architectural heritage in its digital form. For a convincing display we suggest a nightly projection in situ, showing the virtual reconstructions in their original place. In order to achieve this form of projection, we address the challenge to project over existing architecture taking the uneven and textured projection surface of the existing architecture into account. This will be achieved through a projection mapping technique, correcting the geometric distortion as well as the texture variation of the naturally uneven projection environment. As a result of this work we aim at a nightly projection of a virtual reconstruction of past times for the public to enjoy. With this approach a virtual time travel through different epochs is possible and made visible. The innovative technique of this approach lies in its mixed reality visualisation of architectural heritage: the (virtual) past is projected over the present in its original location.