4D Performance Modelling and Animation

Visual reconstruction of dynamic events as 3D video, such as an actor performance or sports action, has advanced to the stage where it is possible to achieve free-viewpoint replay with a quality approaching the captured video. In this talk we present research going beyond replay to allow the creation of 4D models which support interactive animation control from captured performance whilst maintaining the realism of video. 4D models are constructed by alignment of reconstructed mesh sequences into a temporally coherent structure. Recent work has introduced a non-sequential approach to non-rigid mesh sequence alignment which constructs a shape similarity tree to align across a database of multiple sequences. This avoids problems of drift and tracking failure associated with sequential alignment approaches. Temporally aligned 4D models provide the basis for parameterisation of multiple related sequences to give continuous interactive movement control. Representation of multiple sequences in a 4D parametric motion graph enables transition between multiple motions to achieve interactive character animation.