There is disclosed an apparatus for sharpening an edge in a video image. The apparatus comprises: 1) a first circuit for determining a first luminance value of a first pixel associated with the first edge and a second luminance value of a second pixel associated with the first edge, wherein the first...http://www.google.de/patents/US6600517?utm_source=gb-gplus-sharePatent US6600517 - System and method for improving the sharpness of a video image
