Patent ID: 7815124
Filing Date: 2010-10-19
Classification: B41M,B42D,H04N

Abstract:
1. A computerized method to reduce at least one of image washout and blurring caused by the fluorescence of a covert image that is to be transferred to an identification document for printing, said method comprising, prior to the transfer of the covert image: providing a computer system, the computer system running executable software, the executable software running one or more edge detection algorithms, at least one digital image to be processed by the computer system using the executable software, the digital image being stored in association with the computer system and comprising image pixels of varying degrees of dark and light; the computer system accessing and retrieving the digital image that is to be used as a model to generate a covert image that is to be printed using the computer system on the identification document using a fluorescing medium; the executable software increasing contrast in the digital image, the step of increasing contrast including making dark pixels relatively darker and light pixels relatively lighter; the executable software identifying one or more contour(s) of the image pixels of the digital image where luminosity of the increased-contrast digital image changes more sharply than at adjoining regions in the image using the computer system; the executable software, in the step of identifying contours of image pixels of the digital image further comprising the steps of generating a horizontal edge image comprising horizontal edge components, generating a vertical edge image comprising vertical edge components and summing the vertical and horizontal edge images to form a composite image; the executable software emphasizing said contour(s) by iteratively adding copies of the composite image onto itself wherein each added copy is offset with respect to the previous copy; and the computer system forming a master for guiding printing of the covert image.