Translations:Kdenlive/Manual/Effects/Alpha manipulation/6/en

This image shows the situation with alpha info now added via the blue screen method. The blue screen effect is also known as "Color to alpha" [1] and all the blue screen effect does is say that where the video is blue, the alpha value is 0 (i.e. transparent). So now that we have alpha information, the second track's image shows through where the alpha channel says the image should be transparent.