Houdini 20.5 Nodes Copernicus nodes

Premultiply Copernicus node

Premultiplies an RGBA layer.

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This node premultiplies or un-premultiplies an RGBA layer. Premultiplying means multiplying the R, G, and B channels by the Alpha channel. Un-premultiplying means dividing instead of multiplying.

Parameters

Mask

The amount of the new value to mix in with the original value. Higher values mix in more of the new value. Lower values mix in less of the new value. A value of 1 means this node uses only the new value.

See Mask for more information.

Operation

Premultiply by Alpha

Multiplies the R, G, and B channels by the Alpha channel.

Un-Premultiply by Alpha

Divides the R, G, and B channels by the Alpha channel.

Inputs

source

The original layer to premultiply.

mask

An optional per-pixel mask amount that’s scaled by the Mask parameter.

Outputs

premult

The original layer premultiplied.

Copernicus nodes