Piecewise parametric interpolation for temporal compression of multijoint movement trajectories

Computer animation of sign language used by deaf individuals has been produced from 51 time-varying trajectories of the fingertips, the centers of rotation of the joints of the hands and arms, and facial landmarks. These trajectories are sampled at 1/5th the NTSC video frame rate and interpolated using piecewise sequences of cubic Bezier splines. The resulting trajectories are used to control sparse, stick figure animations of sign language resulting in considerable spatiotemporal compression with intelligibility in the range of 90%. This method introduces an additional 5:1 compression in the temporal domain that has not been previously exploited, and is potentially useful in sign language telecommunication, multimedia presentations, and gesture recognition