Channel Operators/Alpha Channel Coring

The Alpha Channel Coring operator is often used with the Chroma Key operators. The Alpha Channel Coring filter shrinks the alpha channel and has separate settings for top, left, bottom, and right.

Example:
There is a black outline on the edge of the shirt in the example below, caused by the chroma keying. By adjusting the Right radius property, it is possible to shrink the alpha channel.

Without Alpha Channel Coring Operator

With Alpha Channel Coring Operator