“Key Change” by Bogart

  • ©Rod G. Bogart  The University of Utah


SIGGRAPH Video Review:




    Key Change


Company / Institution / Agency:

  • The University of Utah


    In this film computer generated objects appear to reside in a photographic background.The animated objects are obscured by and throw shadows on photographic objects. Models representing objects in the photo were created and used to obscure the animated objects with a ray tracing algorithm. The resulting image of the animated objects with photo-object shaped holes, is then composed over the original photo. A shadow mask, created for the regions of the photo that are shadowed by animated objects, is applied to the photo image by inverting a simple shading equation. This work was performed as part of the Alpha-1 research project at the University of Utah. The ray-tracer is an extension of the Alpha-1 software. The objects are B-spline surfaces created with the Alpha-1 Modeling Systems. The final motion blurred frames were generated on forty HP 320 workstations at the university during idle hours.

Additional Contributors:

    Created by: Rod G. Bogart
    Music by: Jimmy H. Mikalavcic

Animation / Video Overview: