COMBINING 2D FEATURE TRACKING AND VOLUME RECONSTRUCTION FOR ONLINE VIDEO-BASED HUMAN MOTION CAPTURE

摘要

The acquisition of human motion data is of major importance for creating interactive virtual environments, intelligent user interfaces, and realistic computer animations. Today's performance of off-the-shelf computer hardware enables marker-free non-intrusive optical tracking of the human body. In addition, recent research shows that it is possible to efficiently acquire and render volumetric scene representations in real-time. This paper describes a system to capture human motion without the use of markers or scene-intruding devices. Instead, a 2D feature tracking algorithm and a silhouette-based 3D volumetric scene reconstruction method are applied directly to the image data. A person is recorded by multiple synchronized cameras, and a multi-layer hierarchical kinematic skeleton is fitted to each frame in a two-stage process. The pose of a first model layer at every time step is determined from the tracked 3D locations of hands, head and feet. A more sophisticated second skeleton layer is fitted to the motion data by applying a volume registration technique,. We present results with a prototype system showing that the approach is capable of running at interactive frame rates.