Patent ID: 6788826
Filing Date: 2004-09-07
Classification: G06T

Abstract:
A method of correcting artefacts in a processed digital image f represented by a multi-scale gradient representation V={{overscore (V)}0, . . . , {overscore (V)}K-1,SKf} comprising gradient images at multiple resolution levels and a residual image, said gradient representation being obtained by non-linear processing of a multi-scale gradient representation W={{overscore (W)}0f, . . . , {overscore (W)}K-1f,SKf} of an original image f, characterized by the steps of(i) generating a modified gradient representation by modifying the gradient images of V to make their directions pixelwise equal to those of W, and (ii) reconstructing a final output image from this modified gradient represented by applying an inverse multiscale gradient transform (IMG), said inverse transform being such that it yields f when being applied to W.