What is the best package to use to track over large distances

edit

Fedex tracking is comparable service.

very funny....i am talking about visp_track and alvar tracking and others for image tracking. Just started using this software wanted to get some input.

If you want useful answers, please include some context in your question - for example WHAT you're trying to track, which sensors you're using, and maybe even which ROS packages you're already considering.

Poor questions will get poor answers.