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[edit] Luminance Key Node

The Luminance Key Node works by determining the distance in color space between two colors, or the difference between two colors. One color is the key and the other color is being check against the key to determine if it should be transparent or not. Difference matting does not rely on a certain background color, but can have less than optimal results if there is a significant amount of background color in the foreground object.

[edit] Inputs

There are two inputs to this node. The first is an input image that is to be keyed. The second input is a key color. The key color may be selected by using the eyedropper tool in the color select window.

[edit] Outputs

The outputs of the node are the image with the new alpha channel and a matte that represents the alpha channel.

[edit] Controls

[edit] High / Low

This button group ....