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:
Sep. 03, 1996
Filed:
Jun. 24, 1983
Applicant:
Inventors:
John D Lowry, Toronto, CA;
Keith Lucas, Oak Ridges, CA;
Assignee:
Scientific-Atlanta, Inc., Atlanta, GA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
380 14 ; 380 15 ; 380 19 ; 380 20 ;
Abstract
A video signal is encrypted by pseudo-random variation of portions of lines thereof to be horizontally scanned that are devoid of video information. Thus, the durations of line blanking intervals may be varied. The variation is done in accordance with an encryption keys which is employed at the receiver to decrypt the encrypted video signal.