Patent ID: 6721459
Filing Date: 2004-04-13
Classification: G06T

Abstract:
A digital image processing method comprising the steps of:a) embedding a delta function in a digital image; b) subjecting the digital image to an intermediate processing step, the intermediate processing step having a modulation transfer function (MTF) that blurs the image; c) extracting the delta function from the processed digital image; d) estimating the MTF from the recovered delta function; e) generating a sharpening filter that is substantially the inverse of the MTF; and f) applying the sharpening filter to the blurred image to produce an improved image; wherein the step of estimating the MTF from the recovered delta function comprises the steps: d1) selecting a region of data in the block that includes the delta function; d2) setting the rest of the block to zeros; and d3) computing the Fourier amplitude of the selected region.