Reconstructing 3D motion trajectories of particle swarms by global correspondence selection

This paper addresses the problem of reconstructing the 3D motion trajectories of particle swarms using two temporally synchronized and geometrically calibrated cameras. The 3D trajectory reconstruction problem involves two challenging tasks - stereo matching and temporal tracking. Existing methods separate the two and process them one at a time sequentially, and suffer from frequent irresolvable ambiguities in stereo matching and in tracking. We unify the two tasks, and propose a Global Correspondence Selection scheme to solve stereo matching and temporal tracking simultaneously. It treats 3D trajectory acquisition problem as selecting appropriate stereo correspondences among all possible ones for each target by minimizing a cost function. Experiment results show that the proposed method has significant performance advantage over existing approaches.