About two-point tracking

When you use two trackers in the Match Move behavior (two-point tracking), Motion analyzes and records not just the position parameter, but also the scale and rotation parameters. However, you can manually disable any of these parameters (in the Adjust row of the Behaviors Inspector) to achieve different effects.

Match Move Inspector showing the Adjust parameters

In the following example, an oval shape (the foreground object) is match-moved to a video clip of picture frames (the background object) using two-point tracking. In the first three images below, only Position is enabled in the Adjust row of the Behaviors Inspector. As a result, although the camera pushes in toward the picture frames, the white elliptical shape does not change its scale or rotation based on the position of the two trackers.

Canvas showing object being tracked by Position only

In the next example, Position, Scale, and Rotation are enabled in the Adjust row of the Behaviors Inspector. Consequently, the white elliptical shape changes its position, scale, and rotation based on the position of the two trackers, matching the camera’s push toward the picture frames and preserving the illusion that the shape is physically attached to the picture frame.

Canvas showing object being tracked by Position, Scale, and Rotation

Note: When using four-point tracking (corner pinning), scale and rotation are applied to the corner-pinned object. For more information, see Corner pin a foreground object.