To Stabilize A Layer With Motion Tracking (Pro Only) - Adobe AFTER EFFECTS 7.0 Manual

In the Layer panel for the motion source, move the current-time indicator to the frame from which tracking
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should begin.
Using the Selection tool, position and size the feature region so that it surrounds the feature you want to track.
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Note: The search region needs to be only big enough to accommodate the frame-to-frame position change of the feature.
6 In the Tracker Controls panel, click either the Forward Analyze or Backward Analyze button to begin tracking.
Watch the tracking to make sure that it is accurate. If not, click the stop button to stop tracking, and then correct the
problem as described in "Correcting a drifting feature region (Pro only)" on page 346.
When you are satisfied with the position of the feature regions throughout the footage, click the Apply button to
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apply the motion to the effect. After Effects creates keyframes and copies them to the effect point control.
See also
"Placing an effect using effect points" on page 353

To stabilize a layer with motion tracking (Pro only)

If you shoot with a handheld or airborne camera or bump a camera during shooting, you may want to stabilize
footage. Stabilizing smooths unwanted camera movement or unwanted drift (when a subject has drifted out of
position). To stabilize footage, After Effects first tracks the motion in the shot. It then shifts the position and rotation
of each frame as necessary to remove the movement. When played back, the motion appears smooth because the
layer itself moves incrementally to offset the unwanted motion.
Depending on the encoder you use, it is possible to decrease the size of your final output file by stabilizing motion
footage. Random motion, such as from the jostling of a handheld camera, can make it difficult for many compression
algorithms to compress your video.
As with tracking motion to apply that motion to a target, you need to define a feature and search region. However,
for stabilization, you want to select a feature that is stationary within the context of the frame rather than select a
feature that is moving relative to the frame. Tracking a stationary object ensures that you are stabilizing only
unwanted motion. The rules for selecting a good feature are the same for stabilizing and tracking: The feature should
be visible during the entire shot, be of a contrasting color from the surrounding area, have a distinct shape (at least
within the search region), and have a fairly consistent shape and color throughout the shot.
After Effects gives you two options for stabilizing: Position and Rotation. Together these options can compensate for
undesired camera movement in all directions. You generally want to stabilize footage with these options on.
However, in some circumstances you may need to turn one of them off. For example, if you are panning, you would
turn off the Position option but leave the Rotation option on.
In the Timeline panel, select the layer containing footage you want to stabilize.
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Note: The selected layer must include motion or changing frames, such as video source footage, for Stabilize Motion to
be available in the Animation menu. If you want to track motion in still images or a sequence, first pre-compose the layer
by choosing Layer > Pre-compose.
2 Choose Animation > Stabilize Motion or click Stabilize Motion in the Tracker Controls panel. After Effects then
performs the following actions:
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Displays the Tracker Controls panel with the selected layer listed for Motion Source as well as Motion Target.
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Creates a new track and displays its name in the Tracker Controls panel for the Current Track.
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Displays Stabilize for Track Type.
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Adds the new track to the Motion Trackers section of the motion source layer in the Timeline.
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