5. Uniform out-of-focus blur: Defocus of photography
can often be found in many photo images. This type
of blur is primarily due to the following factors: the focal
length, the camera aperture size and shape, the distance
between object and camera, the wavelength of the
incoming light, and the effects due to diffraction. It is difficult
to obtain all of these parameters after a picture has
been taken; however, we can use the uniform out-offocus
model as an approximation of the PSF,