Spacetime Tetrahedra: Image-Based Viewpoint Navigation through Space and Time Christian Lipski, Georgia Albuquerque, Timo Stich, Marcus Magnor

Christian Lipski, Georgia Albuquerque, Timo Stich, and Marcus Magnor: "Spacetime Tetrahedra: Image-Based Viewpoint Navigation through Space and Time", Technical Report no. 12-9, Institut für Computergraphik, TU Braunschweig, December 2008. http://www.digibib.tu-bs.de/?docid=00023968 Part of project "Virtual Video Camera". [pdf] [bib]

Abstract

We present a purely image-based rendering system to viewpoint-navigate through space and time of arbitrary dynamic scenes. Unlike previous methods, our approach does not rely on synchronized and calibrated multi-video footage as input. Instead of estimating scene depth or reconstructing 3D geometry, our approach is based on dense image correspondences, treating view interpolation equally in space and time. In a nutshell, we tetrahedrally partition the volume spanned by camera directions and time, determine the warp field along each tetrahedral edge, and warp-blend-interpolate any viewpoint inside a tetrahedron from the four video frames representing its vertices. Besides fast and easy acquisition to make outdoor recordings feasible, our space-time symmetric approach allows for smooth interpolation of view perspective and time, i.e., for simultaneous free-viewpoint and slow motion rendering.

TU Braunschweig - Fakultät für Mathematik und Informatik - Computer Graphics - Publications - Spacetime Tetrahedra: Image-Based Viewpoint Navigation through Space and Time