User`s guide
Generating the Motion Path
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Setting Target and Search Regions
Once you set up the timeline to produce the desired effect, you need to specify which point
or points you want to track. For each tracker you are using, a Target and Search region can
be defined in the source track. The Target region indicates the area in the media to track. The
Search region indicates the area in the media that the filter should search for the target.
To set Target and Search regions:
1. Click the Preview Monitor icon in the Motion Tracker filter track to open a Preview
window. The Preview window displays the media in the Source track and the onscreen
controls for the Target and Search regions.
The Search and Target regions do not appear in the Composite window. They are only
visible in the Motion Tracker’s Preview window.
2. Select the first keyframe in the Source track. Define the Search and Target regions,
either by dragging the onscreen controls, or by using the parameters in the Search/Target
tab in the Controls window.
In the Preview window, you can drag the handles of either region to adjust the size and
shape of the region.
3. Drag inside the Target region to move both regions at once. Drag between the regions to
move the Search region.
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If the default interpolation is set to Constant in the Preferences window, no keyframes are
generated for the Motion Tracker when you move the tracker target/search region. Save your
effect, exit and re-enter Avid FX, then set the default interpolation to something other than
Constant. After you do that you can open your saved effect and continue to work on it.
Tips for Selecting Target and Search Regions
• A good Target region contains a high-contrast object with good vertical and horizontal
edge definition. Ideally, you should find a pattern that is visible in every frame.
• The Search region should be large enough to accommodate the movement of the Target
region in the subsequent frame. However, processing time increases as the size of the
Search region increases, so do not make the Search region unnecessarily large.
Target region
Search region
Center Point