Circuit for including a copy-inhibit signal with a video signal

• US 5,537,216 A
• Filed: 05/03/1995
• Issued: 07/16/1996
• Est. Priority Date: 01/31/1991
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yamashita, Keitaro, Kawano, Masatoshi
• Primary Examiner(s): Tran, Thai Q.
• Assistant Examiner(s): Chevalier, Robert
• Application Number:
  US08/433,588
• Time in Patent Office: 440 Days
• Field of Search: 358/335, 358/310, 358/342, 380/7, 380/5, 380/10, 380/15, 360/60
• US Class Current: 386/248
• CPC Class Codes: G01B 15/04 for measuring contours or curvatures
• CPC Class Codes: G11B 19/02 Control of operating function, e.g. switching from recording to reproducing
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: H04N 5/913 for scrambling ; for copy protection
• CPC Class Codes: H04N 7/166 Passage/non-passage of the television signal, e.g. jamming, band suppression scrambling and descrambling H04N7/167

Abstract

A spurious signal SSP whose frequency spectrum is located at frequencies [(N+(1/2))·fh] is multiplexed with a luminance signal Y so as to keep an interleaved relation between the spurious signal SSP and the luminance signal Y and the resultant signal is transmitted. When the spurious signal SSP is detected, the recording operation is inhibited. The spurious signal SSP is multiplexed with the luminance signal Y at a level such as not to exert an influence on the picture quality when the video signal is reproduced and seen by a monitor screen.

Claims

1. A video signal recording apparatus, comprising:

an input terminal for receiving a video signal;

recording means for recording said video signal on a recording medium;

detecting means for detecting a copy-inhibit signal combined with said video signal and having a frequency substantially equal to (N+(1/2)·

fh±

fv/2, where N is an integer, fh is a horizontal frequency of said video signal and fv is a vertical frequency of said video signal; and

control means for inhibiting operation of said recording means upon detection of said copy-inhibit signal by said detecting means.

2. The video recording apparatus of claim 1, wherein said recording means comprises video tape recording means for recording said video signal on a video tape.

3. The video recording apparatus of claim 2, wherein said detecting means includes comb filter means for separating the copy-inhibit signal from the video signal.