Motion Volume: Visualization of Human Motion Manifolds

The understanding of human motion is important in many areas such as sports, dance, and animation. In this paper, we propose a method for visualizing the manifold of human motions. A motion manifold is defined by a set of motions in a specific motion form. Our method visualizes the ranges of time-varying positions and orientations of a body part by generating volumetric shapes for representing them. It selects representative keyposes from the keyposes of all input motions to visualize the range of keyposes at each key timing. A geometrical volume that contains the trajectories from all input motions is generated for each body part. In addition, a geometrical volume that contains the orientations from all input motions is generated for a sample point on the trajectory. The user can understand the motion manifold by visualizing these motion volumes. In this paper, we present some experimental examples for a tennis shot form.