Apple Motion 5.1.1 User Manual
Page 1002
Chapter 22
Motion tracking
1002
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Better: This option provides a more detailed analysis, but is slower. This is the recommended
option when the clip contains rotation.
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Track Region: Select this checkbox to define a subject or area to be analyzed. A red overlay
appears in the Canvas. The area outside this overlay ignored. The track region’s onscreen
controls are similar to a shape’s onscreen controls.
For more information on using the Track Region, see
on page 971.
Important:
The Track Region must include some area in which the motion can be extracted. It
should not be used as a mask for the object to track.
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Method: This pop-up menu defines how the stabilization is applied to the clip. There are two
options:
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Stabilize: This method attempts to lock the motion of the principal subject in the shot
to eliminate motion. As a result, the background appears to move around the subject
being tracked.
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Smooth: This method smoothes the apparent motion of the camera, while allowing the
general movement in the frame to proceed. It’s useful for removing jitter from a camera
move. When enabled, this mode has three sliders for each dimension that can be smoothed.
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Translation Smooth: When Method is set to Smooth, use this slider to smooth motion in the X
and Y dimensions.
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Rotation Smooth: When Method is set to Smooth, use this slider to smooth image rotation.
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Scale Smooth: When Method is set to Smooth, use this slider to smooth an uneven zoom.
Note: Don’t set the Scale Smooth above 0 unless you’re positive that the clip is being zoomed.
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Borders: When a clip is stabilized, the resulting transformations made to the stabilized image
may cause moving black borders to appear around the edges of the clip. Stabilized clips
containing extreme horizontal or vertical movement (due to excessive camera shake) may
result in very large black borders.
This pop-up menu defines how such added borders are handled. There are two options:
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Normal: Maintains the size of the stabilized footage. The moving black borders remain
around the edges of the clip.
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Zoom: Expands the clip to fill the Canvas. This prevents black borders from appearing around
the edges, but scales up the stabilized clip, which may degrade image quality.
Tip: You can also eliminate the black borders manually by adjusting the layer’s scale or Z
position in the Properties pane of the Inspector.
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Direction: This pop-up menu specifies the dimension to which the recorded movement is
applied to the analyzed image—Horizontal and Vertical (X and Y), Horizontal (only X), or
Vertical (only Y).
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Adjust: Select any combination of these three buttons to set the transformation to which the
stabilization is applied:
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Position: Stabilization is applied to the position of the analyzed image.
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Scale: Stabilization is applied to the scale of the analyzed image.
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Rotation: Stabilization is applied to the rotation of the analyzed image.
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Tracker: Click the Add button to add trackers to the Stabilize behavior. By default, trackers are
added at the center of the Canvas. A maximum of two trackers can be added to the Stabilize
behavior. When added, Anchor is used to analyze changes in X and Y position, and Rotation-
Scale is used to analyze changes in rotation and scale.
After a tracker is added to a Stabilize behavior, the following occurs:
67% resize factor