3a. Setup: Object Marking

What is Object Marking?

By marking the objects you wish to track on certain frames of your video, ABC Tracker is able to determine the size, visual appearance, quantity, and environment of objects to be tracked. Please mark objects carefully: these marks are used extensively throughout the tracking process.


Sample of Fully Marked Frame

How Many Frames Will be Marked?

Currently, ABC Tracker usually requests object markings on three frames.


How to Mark Objects

Set the Correct Brush Size

Set the brush size to cover the body of the objects, but as little image background as possible.

The brush size can be set using either:

  • The scroll wheel on a mouse, or
  • The "Brush Size" slider underneath the playback video

Mark Each Object

Mark the objects by clicking three times on each object: once on the object's head, once in the center of the object, and once on the object's tail.

While it does not matter whether the head or tail are selected first, the center of the object will need to be the second click.


How to Undo Object Marks

Undoing an Incomplete Mark

If a mark has not yet been completed (i.e. there are only 1 or 2 highlighted circles, and the third click has not been completed), right clicking with the mouse anywhere on the video area will remove the incomplete mark.

Undoing a Completed Mark

If a mark has been completed, right clicking with the mouse on the finished mark will remove only that single mark.


Questions on Object Marking

What if No Objects Exist in Frame?

What if Object has an Abnormal Appearance in Frame?

What if Object is Partially Off of Screen?

What if Part of the Image should be Ignored (Binary Mask)


Read Next: Define Tracking Area