The Pseudo-Alpha compositor composites a foreground image against the background by creating an alpha channel for the foreground image based on the foreground image's upper-left-corner pixel. All pixels in the foreground image that use this color become transparent.
-
Rendering menu > Video Post > Video Post window > Make sure the two child events are in the order you want the Image Layer event to use them. > Select the two events. > Video Post toolbar >
(Add Image Layer Event) > Choose Pseudo-Alpha Compositor from the Layer Plug-in list.
-
Rendering menu > Video Post > Video Post window > Select a Pseudo-Alpha Compositor. > Video Post toolbar >
(Edit Current Event)
Pseudo Alpha compositing
Because only one pixel color becomes transparent, edges of the opaque areas in the foreground image are aliased. Use this method when the foreground image is a bitmap whose format does not have an alpha channel.
There are no setup options for this compositor.
There is also a Pseudo Alpha filter event.
Procedures
To use the Pseudo Alpha Compositor:
- Add two Scene or Image Input events to the queue.
- Select both events and assign an Image Layer event consisting of the Pseudo Alpha Composite Filter.