| 摘要 |
A digital television service protector receives multiplexed program streams. In addition to checking the integrity of all program streams, the protector monitors selected parameters of each stream; so that on detection of a loss in integrity, a failed program stream can be replaced with a substitution stream constructed by the protector to have appropriate parameters matching those of the failed stream. The appropriate parameters may be, for example, program identification taken from the input bitstream which it is replacing. The substitution stream may be error messages, test signals, repeats of information or other appropriate information in suitable form such as image, audio or textual. |
