CIOverlayBlendMode - emcconville/cif GitHub Wiki

CIOverlayBlendMode

Either multiplies or screens the source image samples with the background image samples, depending on the background color. The result is to overlay the existing image samples while preserving the highlights and shadows of the background. The background color mixes with the source image to reflect the lightness or darkness of the background.

• -inputImage <image> : The image to use as an input image. For filters that also use a background image, this is the foreground image.
• -inputBackgroundImage <image> : The image to use as a background image.