To track 2D shapes within a shot, you need to enable the Shape Tracker tool and create an ROI.
To access the Shape Tracker panel and create an ROI:
The Secondaries menu with the Shape Tracker panel appears.
The Shape Tracker is made up of the following components.
(a) Tracker button (b) Tolerance slider (c) Shape button (d) Hide button (e) Analyse backward button (f) Analyse forward button
A tolerance level of 0 (low tolerance) means the object that is being tracked does not change in shape throughout the shot. If an external object passes in front of the tracked object, a low tolerance ensures that the motion of the external object does not get tracked through the analysis.
A tolerance level of 10 (high tolerance) means the object which is being tracked has a slight change in shape throughout the shot. For example, there is slight 3D movement from the shape. If you have set the tolerance level to high, external objects that pass in front of the tracked object may be included in the analysis.