摘要 |
An identification signal is generated to identify a digital signal, such as a digital video signal reproduced by a digital video tape recorder (DVTR), as odd or even. Commencing periodically, such as at the onset of each field interval, identification signals occurring at intervals in the digital signal are sampled, and an odd plurality (e.g., three) thereof determined to be error-free are stored. A synthetic identification signal is generated whose value is determined by the majority of the stored identification signals. The generated signal is then stored, for example, in a cascade of flip-flops, to provide a second synthetic identification signal from the onset of each field interval until the majority of the sampled identification signals is determined. In a circuit for processing a digital video signal, an identification signal for identifying line intervals as even or odd is derived by taking the modulo-two sum of field and frame identification signals to determine the state of the line identification signal at the beginning of each field, and thereafter inverting the identification signal at each line interval.
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