An alternative set of source videos used to provide a different real world view is shown here to help illustrate alpha blending. They use a landscape photo as one and the other is half of a color and half of a black and white gradient photo. First is shown the Aritmetic, Logical, and Graphic-Art views. After that the Porter Duff overlays are shown using the same source videos but with each of the Source videos offset in a different direction so that the generated output is more obvious.
The CINELERRA-GG Community, 2021