The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 24, 1989
Filed:
Oct. 24, 1986
Applicant:
Inventors:
Ronnie D Barnett, Nevada City, CA (US);
Steven M Parkes, Davis, CA (US);
Assignee:
The Grass Valley Group, Inc., Grass Valley, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ; H04N / ; H04N / ;
U.S. Cl.
CPC ...
358160 ; 358 22 ; 358136 ; 358183 ;
Abstract
A video difference key generator has a stored reference video image. An input video image is compared with the reference video image by an absolute difference circuit which substracts corresponding pixels of the two video images, the smaller from the larger, to produce a difference video image. The difference video image may be filtered, and then is input to a transfer function circuit to produce an output which may be used as a key signal for compositing video images.