Image quality improvement by hierarchical pattern matching with variable size templates

摘要

Image quality is improved by the prevention of aliasing using a hierarchial pattern matching operation incorporating variable-sized templates. A template which is passed over an image is partitioned into a plurality of sub-templates. The corner sub-templates of the template are eliminated from consideration. It is determined whether the remaining sub- templates contain anything other than all-white or all-black. If a sub- template reports something other than all-white or all-black, the sub- template is checked with a matching region. The matching region defines the action to be taken on the central pixel beneath the template. The pattern matching operation prevents the necessity for an increased memory capacity while providing increased levels of gray for each pixel.