Unpremultiply
Divides selected channels by a specified alpha channel. If the alpha channel on a pixel is 0, then that pixel will remain the same as the input.
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.
in
The input image
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 divided by itself - it will remain the same as the input.