Using Mimic Source for Four-Corner Pinning
Depending on your source footage, you might need to corner-pin an element using
reference points that are in a different position from the final pinned size of the foreground
element. You do this by offsetting the trackers using the Mimic Source option. In the
basic example below, the reference patterns to be tracked (the dot markers) are located
inside the picture frame, rather than at the corners.
The orange visual aid (the orange
outline) represents the resulting
size of the corner-pinned image.
The orange visual aids circle the
tracking reference points.
Because the tracking reference points (the dot markers) are not flush with the inside edge
of the frame, you must offset the image from the four trackers. Otherwise, the final
corner-pinned image appears too small, as in the example below.
Note: In this example, you could track to the corners of the frame. However, the steps in
the following section demonstrate a simple example of how to use the Mimic Source
parameter to four-corner pin an object when your predefined tracking markers (markers
placed on the objects in the physical set) are offset from the reference points to which
you want to track.
To track reference points that are offset from the foreground image
Use one of the workflows described above (see
Four-Corner Pinning with Match Move
to set up a four-corner pin using the Match Move behavior.
From the Transform pop-up menu in the Behaviors Inspector, choose Mimic Source.
In the Canvas, drag the trackers to the tracking markers.
The image is not affected and remains locked to its original placement.
Click the Analyze button in the HUD or Behaviors Inspector.
The foreground element is pinned on the background element.