Adobe After Effects - Manual (Page 243)

Options
Note:
Feature Center
Feature Size
Search Offset
Search Size
Confidence
Attach Point
Attach Point Offset
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Select Stop Tracking to stop the motion tracking.
Select Extrapolate Motion to estimate the position of the feature region. Attach-point keyframes aren’t created for low-confidence frames, and
attach-point keyframes for the low-confidence frames from previous tracks are deleted.
Select Adapt Feature to use the original tracked feature until the confidence level falls below the specified threshold. At that point, After
Effects adapts the tracked feature to be the contents of the feature region in the frame preceding the one that has low confidence and
continues tracking. This option isn’t available if Adapt Feature On Every Frame is selected in the Motion Tracker Options dialog box; enabling
feature adaptiveness causes After Effects to adapt the feature region with every frame regardless of the confidence level.
Opens the Tracker Plug-in Options dialog box, which includes options for the AE Original Built-in Tracker. This command is only
available if you choose to use the older After Effects tracker plug-in.
To show or hide motion paths in the Layer panel, select or deselect the Display Motion Paths option in the panel menu of the Tracker
panel. (The panel menu is the menu that you access by clicking the icon in the upper-right corner of a panel.) You can also use commands in this
menu to add a new track point, reveal the current track in the Timeline panel, and toggle whether the feature region magnification is enabled.
Motion tracking properties in the Timeline panel
Each time you click Track Motion or Stabilize Motion in the Tracker panel (or choose Animation > Track Motion or Animation > Stabilize Motion), a
new tracker is created for the layer in the Timeline panel. Each tracker contains track points, which are property groups that store the tracking data
after tracking has been performed. Trackers are grouped in the Motion Trackers property group for each layer in the Timeline panel.
To show a tracker in the Timeline panel, select the tracker from the Current Track menu in the Tracker panel and press SS.
You can rename trackers and track points and modify and animate their property values in the Timeline panel just as you do for other layer
properties and property groups. You must click Apply in the Tracker panel to apply the property changes to the target.
Position of the center of the feature region.
Width and height of the feature region.
Position of the center of the search region relative to the center of the feature region.
Width and height of the search region.
Property through which After Effects reports the amount of certainty regarding the match made for each frame. In general,
Confidence is not a property that you modify.
Position assigned to the target layer or effect control point.
Position of the attach point relative to the center of the feature region.
Adjust the track point
When you set up motion tracking, it’s often necessary to refine your track point by adjusting the feature region, search region, and attach point.
You can resize or move these items independently or in groups by dragging using the Selection tool. To help you define the area to be tracked,
the image area within the feature region is magnified to 400% while you move the region.
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