| 摘要 |
A system for scrambling and descrambling a composite video signal having content and an associated composite synchronization signal. The system comprises an apparatus for scrambling the composite video signal, an apparatus for recovering the composite video signal and a transmission apparatus for transmitting the scrambled composite video signal between the scrambling apparatus and the recovering apparatus. The apparatus for scrambling the composite video signal including a pseudo vertical synchronization signal generator, a pseudo horizontal synchronization signal generator, a combiner for combining the pseudo vertical and horizontal synchronization signals, and an adder for adding the combined pseudo vertical and horizontal synchronization signals into the composite video signal. The apparatus for recovering the composite video signal from the composite video signal with the added combined pseudo vertical and horizontal synchronization signals includes a locator for locating the associated composite synchronization signal in the composite video signal and a circuit for removing the added combined pseudo vertical and horizontal synchronization signals from the composite video signal.
|
