Mask out objects with garbage mattes – Adobe Premiere Pro CS3 User Manual
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ADOBE PREMIERE PRO CS3
User Guide
376
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In the Effects panel, click the triangle to expand the Video Effects bin and then click the triangle to expand the
Keying bin.
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Drag the Track Matte Key to the superimposed clip.
6
In the Effect Controls panel, click the triangle next to the Track Matte Key name to expand its settings.
7
Click the Matte setting pop-up menu with the down-pointing triangle and choose the video track containing the
track matte clip.
8
(Optional) If you’re animating the Track Matte Key over time, make sure that the current-time indicator is in the
position you want. Click the Toggle Animation icons of the settings you want to adjust.
9
Click the Composite Using pop-up menu and choose one of the following:
Matte Alpha
Composites using the track matte clip’s alpha channel values.
Matte Luma
Composites using the track matte clip’s luminance values.
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(Optional) Select the Reverse option to invert the values of the track matte clip.
To retain the original colors in the superimposed clip, use a grayscale image for the matte. Any color in the matte
removes the same level of color from the superimposed clip.
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(Optional) If you’re animating the Track Matte, move the current-time indicator either in the Effect Controls
panel or Timeline panel and change the Track Matte Key settings.
A new keyframe appears in the Effect Controls timeline when you change the settings. You can also adjust the inter-
polation between keyframes by editing the keyframe graph. Repeat this step as needed.
See also
Mask out objects with garbage mattes
Sometimes the subject of a scene is properly keyed except for undesired objects. Use a garbage matte to mask out
those objects. Depending on the shape of the mask, you can use the Four-Point Garbage Matte, Eight-Point Garbage
Matte, or Sixteen-Point Garbage Matte. More points let you define more complex mask shapes.
The Garbage Matte keying effect provides settings that represent the x and y pixel coordinates of each point of the
garbage matte, measured from the top left corner of the frame. Changes appear in the Preview view of the Program
Monitor.
The microphone (left) is masked out by repositioning image handles in the Preview view of the Program Monitor (center), creating a garbage
matte that is then keyed and superimposed over a background (right).
1
In the Timeline panel, place the clip you want to superimpose in a track above the one containing the background clip.
April 1, 2008