The teachings provided herein disclose a method for corner sharpening in
the display of a bitmapped digital image. The method includes the steps
of selecting a target pixel location within the digital image; observing
a set of pixels within a pixel observation window superimposed on the
digital image relative to the target pixel location; generating
edge-state codes for a plurality of pairs of neighboring vectors of
pixels within the pixel observation window; generating
corner-identification codes from the plurality of edge-state codes using
at least one look-up table so as to thereby identify corner pixels; and,
assigning a pixel value in an output image plane in a location
corresponding to the target pixel in the input image, such that assigned
value extends a corner where indicated by a corner identification code,
thereby producing a sharpening effect. The method may be used for
improving the print quality of line-art corners and other fine details as
found in both font and image data.