Using Real Shadows to Create Virtual Ones

  • Claus B. Madsen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2749)


In Augmented Reality (AR) real imagery is superimposed by computer graphics renderings of virtual objects. This paper addresses the problem of creating the illusion that the virtual objects cast credible shadows in the real scenario. A step towards this is to be able to detect shadow regions in images of natural scenes, and this paper describes an approach to such shadow detection. The shadow detection can distinguish between directly lit areas, penumbra (half-shadow) areas, and umbra (full shadow) areas. Furthermore, it is demonstrated how virtual shadows can be created which appear very similar to the real shadows.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Claus B. Madsen
    • 1
  1. 1.Laboratory of Computer Vision and Image AnalysisAalborg UniversityAalborg EastDenmark

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