Instruction Manual

Chapter 22 Motion tracking 1001
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Bottom Right: Available when four-point tracking is enabled (when Four Corners is chosen
from the Type pop-up menu) and the Match Move behavior references another behavior (such
as Analyze Motion), this pop-up menu lets you select the tracker from the referenced behavior
you want to apply as the bottom-right tracker.
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Bottom Left: Available when four-point tracking is enabled (Four Corners is chosen from the
Type pop-up menu) and the Match Move behavior references another behavior (such as
Analyze Motion), this pop-up menu lets you select the tracker from the referenced behavior
you want to apply as the bottom-left tracker.
Stabilize controls
The Stabilize behavior uses a dierent method to analyze movement in a clip than the Match
Move and Analyze Motion behaviors. Generally, you do not use trackers to stabilize a clip. The
behavior’s sophisticated method of motion estimation tracks every pixel in one frame to the
subsequent frame. A motion vector is calculated based on this analysis. The analysis can be
performed on the entire clip, or on a track region. A track region is a user-dened area of a clip
that is analyzed.
If the result of the analysis requires additional correction, you can perform manual tracking on
noncontiguous time regions of the clip. For example, if an additional camera bump aects frames
350 to 380, you can add a tracker to analyze that portion of the clip. The data recorded from the
analysis is added to the data recorded by the tracking to further smooth the clip.
In addition to considering horizontal, vertical, or horizontal and vertical movement in the clip, the
Stabilize behavior also looks at position, scale, and rotation. The Stabilize behavior can only be
applied to footage objects (a QuickTime movie or an image sequence).
For information on using the Stabilize behavior, see Stabilize workow on page 971.
Note: When Smooth is chosen from the Method pop-up menu, additional parameters become
available in the HUD and Inspector.
Parameters in the Inspector
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Source: Drag a source object for the behavior to this well. The source object can be another
Stabilize behavior or a footage object. To clear a Source well, drag the item away from the well
and release the mouse button.
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Action pop-up menu: Choose from a list of tracking data (from other tracking behaviors) in
the project.
Note: When you select an option from the Action pop-up menu, the Add button becomes
unavailable, allowing you to select a tracker for the Source well.
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Movement: Click the Analyze button to begin the motion-tracking analysis. When you click
Analyze, a status window appears and displays the tracking progress. To stop the analysis, click
the Stop button in the status window or press Esc.
When using the Stabilize behavior (without trackers), the track begins at the start of the clip,
rather than the current playhead position.
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Quality: This pop-up menu denes the level of detail for the motion analysis. There are two
options:
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Faster: This option allows for a faster operation, but motion analysis is less detailed.
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