Performance evaluation metrics and statistics for positional tracker evaluation

This paper discusses methods behind tracker evaluation, the aim being to evaluate how well a tracker is able to determine the position of a target object. Few metrics exist for positional tracker evaluation; here the fundamental issues of trajectory comparison are addressed, and metrics are presented which allow the key features to be described. Often little evaluation on how precisely a target is tracked is presented in the literature, with results detailing for what percentage of the time the target was tracked. This issue is now emerging as a key aspect of tracker performance evaluation. The metrics developed are applied to real trajectories for positional tracker evaluation. Data obtained from a sports player tracker on video of a 5-a-side soccer game, and from a vehicle tracker, is analysed. These give quantitative positional evaluation of the performance of computer vision tracking systems, and provides a framework for comparison of different methods and systems on benchmark data sets.