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:
Jun. 02, 1992
Filed:
Feb. 27, 1991
Applicant:
Inventors:
Paul E Greaves, Rancho Cordova, CA (US);
Michael R Moore, Folsom, CA (US);
Stephen G Perlman, Mountain View, CA (US);
Laurence A Thompson, Saratoga, CA (US);
Assignee:
Apple Computer, Inc., Cupertino, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G09G / ;
U.S. Cl.
CPC ...
340701 ; 340720 ; 358 31 ;
Abstract
A circuit for converting RGB to composite video. The circuit is particularly useful in a video overlay application. Notch filters are used both in the video path and keying path. The notch filters are centered at frequenices equal to the dot clock frequency of the RGB divided by integers where the result of this division falls within the chroma subcarrier spectrum.