Premultiply

Multiplies selected channels by a specified alpha channel.

user

Container for user-defined plugs. Nodes should never make their own plugs here, so users are free to do as they wish.

out

The output image generated by this node.

enabled

Turns the node on and off.

channels

The names of the channels to operate on. Names should be separated by spaces and can use Gaffer’s standard wildcards.

alphaChannel

The channel to use as the alpha channel. The selected channel does not have to be ‘A’, but whichever channel is chosen will act as the alpha for the sake of this node. This channel will never be multiplied by itself - it will remain the same as the input.