System and method for image scaling

• Main Authors: QIANG ZHU, DANIEL, JOHN STEC, KEVIN
• Format: Patent
• Language: English; French; German
• Published: 04.10.2000
• Edition: 7
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CALCULATING; COMPUTING; COUNTING; CRYPTOGRAPHY; DISPLAY; EDUCATION; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; SEALS

A system and method for format conversion for use with images containing mixed video and computer generated imagery. A first intermediate scaled image is generated using a first interpolator which has a relatively wide passband and a narrow transition band to the stop band. This interpolator retains high frequency components in the interpolated image but may introduce ringing distortion adjacent to strong edges. The first intermediate scaled image is then processed through an edge extractor which extracts strong edges but ignores any associated ringing distortion. The output signal of the edge detector is a scaled edge image. Next, a second intermediate scaled image is generated using a second interpolator which has a narrower passband and a more gradual transition band. This interpolator produces an image having reduced high frequency components relative to the original image. Then the scaled edge image is added to the second intermediate scaled image to produce a converted image having substantially the same high frequency components as the first intermediate scaled image but no ringing distortion components.