User`s guide

Working with Pre-Compositions
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• Click the Add 3D Plane button in the timeline.
2. Assign the media you are using for the mask to this new track.
Use the alpha channel of the image file for the mask.
3. Expand the track you want to mask to reveal its Mask tracks.
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If you do not see the Mask tracks in the timeline, go to Edit > Preferences to open the
Preferences window, and select Show Mask Tracks in the General tab.
4. Drag the mask you created into the Mask track as follows:
• For a downstream mask effect, use the shape’s Mask track.
• For an upstream mask effect, use the Mask track nested in the Face track.
Working with Pre-Compositions
When you want to apply a common effect on different media tracks on the timeline, it is best
to use the method of pre-composition. It allows you to composite two or more tracks into
one bitmap 3D plane shape track before any further compositing can be done. Pre-
composition tracks are equivalent to a 3D plane shape with color media, but with the color
media track hidden. You can apply masks and filters as you would with a 3D plane shape.
You can even adjust its size. See “Resizing Media” on page 127.
Shape Mask track
Face Mask track