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USING ADOBE PREMIERE PRO
Effects and transitions
Last updated 1/16/2012
6
In the Effect Controls panel, click the triangle to expand the Image Matte Key settings.
7
Click the Setup button
, browse to the image being used as the matte, and then click Open to select the image.
8
(Optional) If you’re animating the Image Matte Key over time, make sure that the current-time indicator is in the
position you want. Click the Toggle Animation icons for the settings you adjust.
9
Click the Composite Using menu and choose one of the following:
Matte Alpha
Composites the clips using the alpha channel values of the image matte you selected in step 7.
Matte Luma
Composites the clips using the luminance values of the image matte you selected in step 7.
10
(Optional) Select the Reverse option to swap the areas that are opaque and transparent.
11
(Optional) If you’re animating the Image Matte Key, move the current-time indicator either in the Effect Controls
panel or Timeline panel and change the Image Matte Key settings.
A new keyframe appears in the Effect Controls timeline when you change the settings. Repeat this step as needed. You
can also adjust the interpolation between keyframes by editing the keyframe graph.
More Help topics
“
Adding, navigating, and setting keyframes
” on page 415
“
Modify keyframe values
” on page 420
Luma Key effect
The Luma Key effect keys out all the regions of a layer with a specified luminance or brightness.
Use this effect if the object from which you want to create a matte has a greatly different luminance value than its
background. For example, if you want to create a matte for musical notes on a white background, you can key out the
brighter values; the dark musical notes become the only opaque areas.
White background of original (top and left) is removed using the Luma Key effect and composited over underlying layer (right).
Adjust the following settings as necessary:
Threshold
Specifies the range of darker values that are transparent. Higher values increase the range of transparency.
Cutoff
Sets the opacity of nontransparent areas specified by the Threshold slider. Higher values increase transparency.
You can also use the Luma Key effect to key out light areas by setting Threshold to a low value and Cutoff to a high
value.