This tool gives a numeric estimate of image sharpness. It can be used to measure blur caused by motion or an out-of-focus lens. The output value depends heavily on the scene being viewed. Its absolute value does not correspond to any physical quantity and is irrelevant as such. The value however decreases with increasing blurriness and increases when the image becomes crisper.
image: Input image.
frame: A :ref:
coordinate frame <engine/world-coordinates:coordinate-frames>specifying the position of a region of interest in the world coordinate system.
size: The size of the region of interest. If size is undefined (either width or height is NAN), the whole image will be used.
sharpness: The average sharpness of the image or the region of interest.