Time-base correction in a video recording/playback system.

摘要

A video recording/playback system includes in its recording electronics time-base correctors (TBC1, TBC2) both for luma signal and for color-under signal, the time-base corrector (TBC1) for luma signal being used to facilitate comb filtering and the time-base corrector (TBC2) for chroma signal being used to maintain luma/chroma tracking during recording. The video recording/playback system includes in its playback electronics time-base correctors (TBC3, TBC4) both for played-back luma signal and for played-back color-under signal, the time-base corrector (TBC3) for played-back luma signal being used to facilitate comb filtering and the time-base corrector (TBC4) for played-back chroma signal being used to maintain luma/chroma tracking during playback. With appropriate switching, the same pair of time-base correctors (TBC1,2 or TBC3,4) can be used in both the recording and the playback electronics of the video recording/playback system. A detector in the recording electronics determines when there is substantial time-base error in the video signal received for recording and conditions the comb filtering of the luma signal during recording to be carried out in just the spatial domain and not in the frame-to-frame time domain. The recording electronics includes circuitry for signaling the playback electronics, via a recorded signal, that the comb filtering of the luma signal during recording was carried out in just the spatial domain and not in the frame-to-frame time domain. The playback electronics responds to such signaling to adapt the comb filtering of the played-back luma signal to suit. <IMAGE> <IMAGE>