TV LINE AND FIELD DETECTION APPARATUS WITH GOOD NOISE IMMUNITY

摘要

An auxiliary video information decoder for decodinginformation such as closed caption data in a video signal identifiesa desired horizontal line of video in a video signal. A referencepulse in a synchronizing signal is detected followed by thegeneration of first and second window pulse signals occurring atpredetermined delays after detection of the reference pulse. Apulse occurring in the synchronizing signal during the windowpulses indicates the start of the desired horizontal line interval. Afield identification signal may also be generated. Features forimproving noise and phase error immunity when identifying avideo line are provided.