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.

Date of Patent:
Oct. 09, 1990

Filed:

May. 23, 1986
Applicant:
Inventors:

Yoshifumi Saeki, Tokyo, JP;

Shigeru Watanabe, Tokyo, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
380 15 ; 380 20 ;
Abstract

A scrambling method for TV pictures avoids picture deterioration by level compressing only selected horizontal flyback portions of the video signal to effect scrambling. A key signal is superposed on selected horizontal synch signals and, when removed at the decoder, enables level expansion of those horizontal flyback portions compressed in order to allow the TV receiver to effect synchronization. Data signals for enabling or disabling reception of particular programming such as paid programs may be superimposed on other selected horizontal synch signals.


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