Hide unwanted objects with a garbage matte – Adobe Premiere Elements 12 User Manual
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Composite Using
Reverse
Replacing a background color with another image
A. Upper clip B. Blue Screen automatically makes the background transparent C. Lower clip D. Combined clips
Create transparency with the Track Matte Key effect
1. If you haven’t already done so, add the matte file to the project: Click Add Media and choose Files And Folders. Navigate to the matte file,
and click Open. The matte file should preferably contain only a single shape (for example, a star or a flower).
2. Add a background clip to a track in the Expert view timeline.
3. Add the clip you want to superimpose over the background clip to any track higher than the background clip. This is the clip revealed by the
track matte.
4. On a third track, add the clip that serves as the matte. (To add a third track, drag the matte to an empty area in the Expert view timeline
above the highest video track. A new track is automatically created.)
5. In the Effects panel, expand the Keying category folder, and drag the Track Matte Key effect to the superimposed clip (the clip above the
background clip).
6. Click the Applied Effects button to open the Applied Effects panel.
7. In the Applied Effects panel, expand the Track Matte Key.
8. For Matte, choose the video track that contains the matte.
9. Adjust options as needed:
Select Matte Alpha to composite using the values in the alpha channel of the track matte. Select Matte Luma to
composite using the image’s luminance values instead.
Inverts the values of the track matte.
Tip: 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.
Hide unwanted objects with a garbage matte
Sometimes a color-based keying effect properly removes a background, but undesired objects still appear, such as a microphone or cable. Use a
garbage matte keying effect to mask out those objects. Garbage mattes work well for areas that have clearly defined boundaries but no uniform
color to key. Garbage mattes also work well to clean up unwanted artifacts that a color-based keying effect left behind.
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