The abstract class is the base class for all filters, which can be applied to an image producing new image as a result of image processing or applied directly to the source image without changing its size and pixel format.

The base class is aimed for such type of filters, which require additional image to process the source image. The additional image is set by OverlayImage or UnmanagedOverlayImage property and must have the same size and pixel format as source image. See documentation of particular inherited class for information about overlay image purpose.