Offsetting the Tracking Motion of the Reference

You can apply the tracking information from one point to another point in the image. A dotted line is displayed between the tracker and the offset target, using the Offset Reference tool. This is useful when you want to track a portion of an image that does not have an adequate tracking anchor point.

In this example, we want to replace the green screen in the TV clip with another shot.

However, when entering the stabilizer, we can see that we don't have proper anchor points on the TV clip, where the four corners of our replacement shot are positioned.

To resolve this, we can offset the reference. To do this, proceed as follows:

1. From the Stabilizer Tools menu, select Offset Reference.

   This enables you to place the tracker on a proper anchor point, but apply the tracking data to the original portion of the image, which does not have an adequate anchor point.

2. Place the trackers on adequate anchor points.
   Note: The trackers should be placed relatively close to the offset target, or on an anchor point that follows the same movement as the offset target, otherwise the detected motion will be off and will drift from the motion of the offset target.
   A dotted line is displayed between the tracker and the offset target.

   
3. Gang the trackers.
4. Enable Auto Update Reference.
5. Press Analyze.
   

   The motion is tracked. The reference is the anchor point on which the tracker was placed, but the motion is applied to the offset target.

6. Exit the Stabilizer.

   The tracking data is applied to the offset targets. The corners of the replacement image are still at their original position, where there were no adequate anchor points, but the motion and the positioning is correct.