Appearance-free Tripartite Matching for Multiple Object Tracking

Multiple Object Tracking (MOT) detects the trajectories of multiple objects given an input video, and it has become more and more popular in various research and industry areas, such as cell tracking for biomedical research and human tracking in video surveillance. We target at the general MOT problem regardless of the object appearance. The appearance-free tripartite matching is proposed to avoid the irregular velocity problem of traditional bipartite matching. The tripartite matching is formulated as maximizing the likelihood of the state vectors constituted of the position and velocity of objects, and a dynamic programming algorithm is employed to solve such maximum likelihood estimate (MLE). To overcome the high computational cost induced by the vast search space of dynamic programming, we decompose the space by the number of disappearing objects and propose a reduced-space approach by truncating the decomposition. Extensive simulations have shown the superiority and efficiency of our proposed method. We also applied our method to track the motion of natural killer cells around tumor cells in a cancer research.