Simultaneous Out-of-focus Blur Estimation And Restoration For A Digital Auto-focusing System

111. PROPOSED IMAGE DEGRADATION SYSTEM Digital image restoration based on estimated PSF Ab8tractIn order to increase accuracy in estimating the point spread function (PSF) of out-of-focus blur, we subdivided the input image and then averaged PSFs from each sub-image. The PSF of each subimage is estimated by differentiating step response along the appropriately estimated edge direction under assumption that an image usually has piece-wise linear boundary between an object and background. Once the averaged PSF is obtained we can use any kind of image restoration filter according to a speciflc application requirements, such as computational complexity or processing time.