OpenCV 3 Tracker won't work after reinitialization

Question

I have issue using OpenCV 3 tracking module for tracking. It behaves same, either I use interface class (cv::Tracker) or class with implementation (like cv::TrackerMedianFlo

Answer 1

If you want to track a new ROI (region of interest) then I suggest that you should create a new tracker instead of clearing and trying to reuse a previous tracker. Re-use when you need to call init will provide no extra benefit. As you have observed, re-initializing a tracker is not allowed by default.

But if you want to resume tracking of the same object with your correction, it might be possible by doing following steps (I have not tried it myself yet. following code is just a pseudo code)

Ptr model = tracker->getModel();
Ptr lastTargetstate = getLastTargetState();

// Make changes to lastTargetState (update position etc)

// Set lastTargetState, I am not sure if you need to actually set it
// or just editing the object through pointer should work.
model->setLastTargetState(lastTargetstate);