| 摘要 |
A method for controlling reduction of a ghost image present in a main path baseband television video signal includes the steps of deriving a main path reference pulse and ghost image of the pulse from a successive series of pulses and ghost images of the pulses present during the vertical blanking interval of a present field of the video signal, the derived ghost image having an amplitude less than the amplitude of the derived main path reference pulse; replicating the derived reference pulse and ghost image at a predetermined repetition rate substantially throughout the useful picture area of the present field interval; generating a signal used for correlation which is delayed in time from the occurrence of the beginning of the present video field; correlating the replicated ghost image with the signal used for correlation to ascertain a location of coincidence in order to provide a correction pulse indicating the delay period and amplitude of the ghost image of the pulse; generating at least two control signals respectively related to the correction pulse: establishing a ghost reduction network structure for the present field in response to the two said control signals and maintaining the established structure throughout the present field and until the ghost reduction network structure is reestablished by the foregoing steps during subsequently occurring fields; and, passing the main path baseband television video signal through the network during the present field and combining a function related to determined amplitude and delay period of the ghost image with the baseband television video signal in order to reduce the amplitude of the ghost image present in the video signal.
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