发明名称 |
Anti-Copy Protection for a Video Signal |
摘要 |
An apparatus and method for applying anti-copy protection to a raster-scanned video signal are described. A square waveform 52 is added to the vertical synchronisation pulses 50 of the video signal. The effect of the waveform is not apparent until it has been recorded by a video cassette recorder. The anti-copy protected video signal can therefore be viewed normally on a display device at or near to the picture quality intended by the originator of the video signal, but once recorded, exhibits a reduction in picture quality which makes the video signal quite unattractive to view. |
申请公布号 |
US2009297125(A1) |
申请公布日期 |
2009.12.03 |
申请号 |
US20090463209 |
申请日期 |
2009.05.08 |
申请人 |
DWIGHT CAVENDISH SYSTEMS LIMITED |
发明人 |
WIJNEN ARIE;TAN BAOLIN |
分类号 |
H04N5/91;H04N5/04;H04N5/913;H04N7/167 |
主分类号 |
H04N5/91 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|