Corner sharpening of text and line art in a super resolution anti-aliasing image path

Abstract

A method for sharpening the corners of digital image data within an anti-aliasing image path so as to overcome corner rounding when displayed or printed. The method comprises stepping a window across the image data and comparing that windowed data to templates or performing Boolean logic and arithmetic operations on the image data. Upon determining a match or a corner detection, pixel values are substituted in the identified pixel locations to achieve a clustering of the substituted pixel values about the corner structure producing a corner-enhanced digital image. Filtering and sampling are then performed according to an anti-alias operation to the corner-enhanced image to produce an anti-aliased corner enhanced image. The data substitution will achieve a localized clustering or 'ear' of toner/ink, or in the alternative for inside corners the localized clustered absence of toner/ink. The result of this clustering is a sharpening of the corners so that they display or print as intended by the bitmap.