An alpha matte is generated from image forming elements of an image. For each of one or more of the image forming elements: a respective representative foreground value is determined from one or more of the image forming element values; the respective representative foreground value and the value of the image forming element are normalized with respect to a threshold level; and a respective value of the alpha matte is generated from an evaluation of the normalized image forming element value in relation to the normalized representative foreground value.