ADOBE AFTER EFFECTS 7.0
User Guide
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by clicking Edit Target and choosing a new target from the Layer pop-up menu in the Motion Target dialog box. The
Edit Target button is not available if Raw is selected for Track Type.
Options Opens the Motion Tracker Options dialog box, through which you can improve the accuracy of tracking
and select third-party tracker plug-ins.
Analyze, Reset, and Apply controls (Pro only)
You use the Analyze, Reset, and Apply controls only when you are ready to begin tracking. The Analyze controls
initiate tracking, while the Reset and Apply controls either delete the tracking data or apply it to the target layer.
Analyze Begins the frame-to-frame analysis of the track point in the source footage. Use the following controls for
Analyze: Step Back to analyze the current frame by stepping back to the previous frame. Analyze Backward
to analyze from the current-time indicator backward to the beginning of the work area or footage. Analyze
Forward to analyze from the current-time indicator to the end of the work area or footage. Step Forward to
analyze the current frame by advancing to the next frame.
Note: The Analyze Backward and Analyze Forward buttons change to a Stop button while analysis is in progress.
Reset Restores the feature region, search region, and attach point to their default positions and deletes the tracking
data from the currently selected track. Tracker Control settings and keyframes already applied to the target layer
remain unchanged.
Apply Sends the tracking data (in the form of keyframes) to the target layer or effect control point.
Tracker Controls (Pro only)
Track Name Indicates the track selected in the Current Track menu in the Tracker Controls panel.
Tracker Plug-in Sets the tracker plug-in used to calculate the tracking data for this track. By default, this option
displays Built-in, the only tracker plug-in included with After Effects.
Channel Specifies the comparison method to use for tracking. RGB compares the RGB values in the feature region;
select if the feature is a distinct color. Luminance compares the brightness value in the feature region; select
Luminance if the feature has high contrast, or brightness, compared to the surrounding objects and background
(such as a burning candle carried through a room). Saturation compares the density of color in the tracking region;
select Saturation if the feature has a high concentration of color, surrounded by variations of the same color (such as
a bright red scarf against a brick wall).
Process Before Match Temporarily blurs or sharpens an image to improve tracking. Blur reduces noise in the
footage. Usually a value of 2 to 3 pixels is enough to produce better tracks in grainy or noisy footage. Enhance
exaggerates or refines the edges of an image and makes them easier to track.
Note: After Effects blurs or enhances the footage only for tracking, restoring it to its original state after tracking.
Track Fields Tracksthemotioninbothvideofieldsofinterlacedvideoanddoublestheframeratetoensurethatboth
video fields are tracked.
Subpixel Positioning Specifies fractional position keyframes to match the specified feature region. When deselected,
the tracker rounds off position keyframes to the nearest pixel.
Adapt Feature On Every Frame Causes After Effects to adapt the feature region during tracking to better assist in
tracking the feature in subsequent frames.
If Confidence Is Below Makes the tracking perform a chosen action (stop, continue, adapt, or extrapolate motion)
when the confidence (accuracy) value falls below a specified threshold.
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