What you learned: Compositing involves combining multiple visual clips by placing them on separate tracks
Use clips that have transparency, or add effects that create areas of transparency, to combine several video clips into a single, final composite image.
An Alpha channel stores information about areas of partial or complete transparency in an image. Titles created in Premiere Pro contain an Alpha channel. Some graphics and video clips also contain an Alpha channel. When they don’t, you can create areas of transparency using effects.
View transparent areas in titles, graphics, and video clips by turning on the Transparency Grid.
To display transparent areas of clips in the monitors:
- Select Transparency Grid from the Source Monitor Settings menu or Program Monitor Settings menu.
Rulers and guides
When positioning a title, or any clip that contains transparency, in front of another clip, use rulers and guides in the Program Monitor to place the image exactly where you want it.
- Choose Show Rulers from the Program Monitor Settings menu (the wrench icon).
- Choose Show Guides from the Program Monitor Settings menu, or drag guides out from the rulers in the Program Monitor.
- From the Program Monitor Settings menu, choose Snap In Program Monitor, so that titles, graphics, logos, and other clips snap to the guides.
Create transparency using effects
Apply an opacity mask to create areas of transparency in a clip:
- Select a foreground clip, and open the Effect Controls panel.
- Under Opacity, choose Create Ellipse Mask. Parts of the background clip instantly appear outside the mask shape.
- With the opacity mask selected in the Effect Controls panel, go to the Program Monitor and drag the mask into position.
- In the Program Monitor, drag any of the edge control points to adjust the mask.
- In the Program Monitor, drag outward on the open circle at the end of the handle to feather the edge of the mask.
Tip: When a graphic comes with an Alpha channel, you can simply drop the graphic on top of everything else in the Timeline, and it is instantly positioned in the frame with all opaque images showing through the transparent areas.