Encoder for superimposing encoded character data or command data in the vertical blanking interval for regulating video receiver functions

摘要

An encoder disconnects video data between a video source and a video using device only during 21H in the vertical blanking interval. During 21H, it applies locally generated coded data signals, in a format detectable by conventional data decoding devices, to the video using device. The video source may be a camera or tape playback, and the using device may be a TV set or a video tape recorder.