Resolution conversion for anti-aliased images using loose gray scale template matching

摘要

A method for resolution conversion for re-sampling anti-aliased images is disclosed which decreases bandwidth costs associated with anti-aliased line art and other costs associated with interpolating these images to a desired resolution. The present method first involving the receipt of an image which is comprised of bitmap data including at least a plurality of gray-scale pixel tiles that define the image. Then receiving the image data at a first resolution and extracting pixel tile information of the received image at a second resolution. The method has the step of next using loose gray scale template matching on each of the pixel tile information with at least one of a plurality of templates so as to generate pixel-wise looseness interval values there between. Then, outputting a portion of the enhanced pixel tile information wherein the enhanced pixel tile information is formed by a matching of a template with pixel-wise looseness values. Preferably, the input and output resolutions are at different integer values and the first and second resolutions have a non-integer ratio. The input image can also preferably be comprised of gray halftones and the output enhanced pixel tile can be formed of binary pixel data.