| 摘要 |
An input signal such as a HDTV signal is split into a primary signal, which can be decoded if desired, and an secondary signal, which can remain compressed. The primary signal may be delayed and then both signals are transmitted to a receiver. If no error in the primary signal is detected, the primary signal is used to display data. Otherwise, the secondary signal, which arrives before the primary signal and consequently which is available for substitution, is displayed. |
