Quantification of gracefulness from hand trajectory in classical dance motion

Graceful is one of the adjectives about human motion. Graceful motion can give a good impression to the observer. This research focuses on the concept of "graceful motion," as defined by William Hogarth. To quantify the gracefulness of human motion, we propose the measurement method that can extract the "Line of Beauty" from dancer's hand trajectory. We approximate the dancer's hand trajectories by quartic B-spline curves and extract the S-shaped curves using its inflection points. Finally, we quantify the gracefulness using extracted curve's parameters. Through the subjective evaluation, we showed that weak correlation between impression and our quantification result.