Video duplication control system, video playback device, video recording device, information superimposing and extracting device, and video recording medium
US6058243A · kind A · utility
21Cited by
3References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1997 |
| Grant date | May 2, 2000 |
| Priority date | — |
| Expiry date | Oct 15, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2005/9135
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A playback device 10 generates a PN code with a start timing based on a video sync signal, and generates a pseudo random noise (PN) inverse code which has a reverse polarity to that of the PN code with a timing based on the video sync signal. An anti-duplication control signal is spectrally spread using this PN code, superimposed on the video signal and supplied to a recording device. A PN inverse code which is the same as the PN inverse code used in the playback device is also generated in the recording device based on the video sync signal, and reverse spectral spread is performed using this PN inverse code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.