5.1.1

Chapter 22 Motion tracking 958
•
You can apply the animation data of one object (animation created by behaviors or
keyframes, for example) to another object. You do this by dragging an animated source
object from the Layers list into the Source well in a destination object’s Match Move
behavior HUD or Inspector. In this way, you can apply the animated source object’s
movement to the destination object without analyzing the motion of the source object.
Note: You can apply the Match Move behavior to nearly any object type.
•
Stabilize: This behavior removes unwanted motion in a clip, such as camera jitter. The stabilization
can be applied to the horizontal or vertical movement in the clip, or to a combination of
horizontal and vertical movement. This eect can be achieved in any of three ways:
•
The Stabilize behavior can analyze and stabilize a clip without onscreen trackers. In this case,
the Stabilize behavior evaluates the entire frame of a clip using motion analysis to record
the movement of the camera. This behavior oers two ways to use this recorded data: clip
smoothing, which eliminates unwanted jitter while maintaining the general motion of the
camera; and clip locking, which stabilizes a subject. This behavior can analyze and aect
position, scale, and rotation.
•
In addition to full-frame motion analysis, you can add onscreen trackers for one-point
(position) tracking or two-point (position, scaling, or rotation) tracking. When you add
manual trackers to the Stabilize behavior, Motion stabilizes the clip using data from the
trackers rather than from an automated motion analysis. When using this method, the
tracker moves the frame so the track point falls in the same spot in each subsequent frame.
You can also combine these methods; for example, you can track part of a clip with the full-
frame method and then switch to manually added trackers later on.
•
You can load analysis tracks recorded in one Stabilize behavior into another. To load an
analysis track, choose a track from the Action pop-up menu in the destination object’s
Stabilize behavior HUD or Inspector.
Note: The Stabilize behavior can only be applied to footage (a QuickTime movie or an image
sequence).
•
Unstabilize: This behavior does not perform tracking analysis. Instead, the Unstabilize behavior
applies the movement recorded by a Stabilize behavior to a clip or object. Use Unstabilize to
match the camera shake in a movie clip to foreground elements added in post-production. To
load the tracking data, choose a track from the Action pop-up menu, located in the tracking
behavior HUD or Inspector. The Unstabilize behavior can be applied to nearly any object type.
When applicable, you can convert tracking data recorded or referenced by the Match Move,
Stabilize, or Unstabilize behaviors to object keyframes. When converted, the tracking behavior
is removed and the transform keyframes are “baked” into the object. For more information on
converting behaviors, see Advanced strategies to improve tracking results on page 984.
Track Points
The Track Points behavior, a member of the Shape behavior subcategory, lets you do either of the
following:
•
Track the control points of a shape, paint stroke, or mask to reference features on a source clip.
For example, you can draw a mask around a car in a clip and then track the control points of
the mask to the moving car, cutting the car out of the background. You can then apply eects
to the isolated car, and the surrounding image is not aected.
•
Apply existing tracking data recorded by the Analyze Motion, Match Move, or Stabilize
tracking behaviors to the control points of a shape or mask.
67% resize factor