title: A Tube-and-Droplet-Based Approach for Representing and Analyzing Motion Trajectories.
abstract: Trajectory analysis is essential in many applications. In this paper, we address the problem of representing motion trajectories in a highly informative way, and consequently utilize it for analyzing trajectories. Our approach first leverages the complete information from given trajectories to construct a thermal transfer field which provides a context-rich way to describe the global motion pattern in a scene. Then, a 3D tube is derived which depicts an input trajectory by integrating its surrounding motion patterns contained in the thermal transfer field. The 3D tube effectively: 1) maintains the movement information of a trajectory, 2) embeds the complete contextual motion pattern around a trajectory, 3) visualizes information about a trajectory in a clear and unified way. We further introduce a droplet-based process. It derives a droplet vector from a 3D tube, so as to characterize the high-dimensional 3D tube information in a simple but effective way. Finally, we apply our tube-and-droplet representation to trajectory analysis applications including trajectory clustering, trajectory classification & abnormality detection, and 3D action recognition. Experimental comparisons with state-of-the-art algorithms demonstrate the effectiveness of our approach.
authors.forename: Weiyao
authors.initials: W
authors.lastname: Lin
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhou
authors.forename: Hongteng
authors.initials: H
authors.lastname: Xu
authors.forename: Junchi
authors.initials: J
authors.lastname: Yan
authors.forename: Mingliang
authors.initials: M
authors.lastname: Xu
authors.forename: Jianxin
authors.initials: J
authors.lastname: Wu
authors.forename: Zicheng
authors.initials: Z
authors.lastname: Liu