Real and Virtual Shadows in Augmented Reality

In Augmented Reality virtual objects are visually combined with real objects to create the illusion that the virtual objects are in fact just a part of the real scenario. While this presents many interesting challenges, one area has so far received very little attention, namely the issue of shadows, or more precisely the issue of ensuring that the virtual objects are lit and cast shadows in the same way as the real scene. CVMT is developing techniques for estimating the positions of real scene light sources, and for estimating the spectral properties of real shadows, in order to apply this information in the rendering of the virtual objects. The result is that the virtual objects mix with the real scenario in a much more realistic manner. Activities have primarily focused at estimating the parameters of virtual lighting conditions so that these conditions match the real scene lighting conditions in an optimal manner. This allows us to realistically recreate very complicated lighting conditions in real-time. Project under BENOGO (EU IST/FET), and ARTHUR (EU IST), 2002-2005. (Claus B. Madsen, Rune Laursen, Moritz Störring)