Alpha Composite
Description
Composites alpha channels with channel and blend mode options for each of the five sources.
Node Group
Composite.
Controls
Channels
Chooses which channel to use for the composite.
Red
Uses the red channel.
Green
Uses the green channel.
Blue
Uses the blue channel.
Alpha
Uses the alpha channel.
Blend
Selects the composite Blend mode.
Add
The Secondary Matte is added to the Primary Matte.
Subtract
The Secondary Matte is subtracted from the Primary Matte.
Multiply
Produces a result where there is a union of the Primary and Secondary Mattes.
Screen
This looks kind of like the Add blend mode, but highlights are retained as opposed to being burnt out.
Difference
Produces a result where a value exists in the Primary and Secondary Mattes, but not in both.
Darken
Compares the two mattes and takes pixels with the lower value.
Lighten
Compares the two mattes and takes pixels with the higher value.