Quickly key out the background from stock footage shot on black and generate an embedded alpha channel. Very useful for compositing smoke, explosions and similar.
- Alpha From: Select the values which will be used to generate the alpha channel.
- Max RGB: Compares the red, green, and blue values, and uses the highest value for each pixel. These values are then converted to luminance, to generate a grayscale image which is used as an alpha channel for the image.
- Luminance: The luminance channel of the image is directly converted to an alpha channel.
- Average RGB: The red, green, and blue values are added, then divided by three to get an average value for each pixel. These values are then converted to luminance, to generate a grayscale image which is used as an alpha channel for the image.