Viewpoint placement optimization for binocular three-dimensional trajectory measurement of translating and rotating particle swarms

Three-dimensional (3-D) tracking and trajectory measurement of group translating and rotating particles may greatly help applications in collective behavior study, motion measurement, etc. Binocular stereo methods are commonly used to track and measure 3-D trajectories of drifting particles. Nevertheless, binocular methods usually suffer from severe stereo-matching ambiguity facing these situations even if motion constraint is adopted to disambiguate stereo matching. We try to help the disambiguating by optimizing viewpoint placement. We model the stereo-matching ambiguity and test different viewpoint placements upon our geometrical analysis to show the influence on the disambiguation that utilizes motion constraint. When the targets undergo group translation and rotation which are highly ambiguous, we find the optimal viewpoint placement such that stereo-matching ambiguity decreases as fast as possible over time. The optimal viewpoint placement can greatly improve the performance of existing methods.