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. 25, 2007
Filed:
Jan. 31, 2003
John O. Ryan, Woodside, CA (US);
James R. Holzgrafe, Morgan Hill, CA (US);
Mark A. Hollar, Palo Alto, CA (US);
John O. Ryan, Woodside, CA (US);
James R. Holzgrafe, Morgan Hill, CA (US);
Mark A. Hollar, Palo Alto, CA (US);
Macrovision Corporation, Santa Clara, CA (US);
Abstract
Method and apparatus for scrambling a high definition television signal to discourage unauthorized recording of same. While recording per se is not prevented, the resulting recorded signal is rendered unusable due to an induced 'wobble' between the active video and the associated sync pulses. The scrambled television signal is readily viewable on a compliant high definition television set which descrambles the HDTV signal using an encoded indication of the amount of wobble accompanying the HDTV signal. Also provided is a special interface to prevent unauthorized persons from using the indication of the amount of wobble so as to defeat the scrambling. Also provided are method and apparatus for defeating the scrambling method and hence allowing recording of the scrambled video signal.