Invariant trajectory indexing for real time 3D motion recognition

Motion trajectory description plays an important role in motion recognition for many robotic tasks. The previous methods are too high in computational cost for real time recognition. In this paper, we propose a novel indexing method for motion trajectories as a high level invariant descriptor. Trajectories are segmented into basic segments and represented in segment level rather than point level. We index the trajectories by their segment sequences to recognize them. The computational cost is significantly decreased and the experimental results show that this method is effective and it can be used for real time motion recognition. The accuracy is also preserved for long term trajectories.