Tracking motion and stabilizing motion are
essentially the same process, only with a different target and result.
Use Track Motion to track motion and apply the results to a different
layer or effect control point. Use Stabilize Motion to track motion
and apply the results to the tracked layer to compensate for that
motion (for example, to remove camera shake).
a layer, After Effects tracks the motion of a feature in the layer
that should be stationary in the frame, and then uses the tracking
data to set keyframes to perform the opposite motion. You can stabilize
to remove any combination of changes in position, rotation, and
scale, while leaving desired motion unaffected. For example, if
the camera is panning, deselect Position but select Scale and Rotation
as the properties to stabilize.
When you select Rotation
or Scale in the Tracker panel, you set two track points in the Layer
panel. A line connects the attach points; an arrow points from the first
attach point (the base) to the second. If possible, place the feature
regions on opposite sides of the same object, or at least on objects
that are the same distance from the camera. The farther apart the
regions, the more accurate the calculations and the better the result.
Effects calculates rotation by measuring the change of angle of
the line between the attach points. When you apply the tracking
data to the target, After Effects creates keyframes for the Rotation
After Effects calculates scale by comparing the
distance between attach points on each frame with the distance between
the attach points on the start frame. When you apply the tracking
data to the target, After Effects creates keyframes for the Scale
When you track motion using either parallel or perspective
corner pinning, After Effects applies keyframes for the Corner Pin
effect to the layer to scale and skew the target layer as necessary
to fit the four-sided area defined by the feature regions. The feature
regions should lie in a single plane in the real world—for example,
on the side of a bus, on the same wall, or on the floor. The attach
points should also all lie in a single plane, but not necessarily
the same plane as the feature regions.