HDTV VIDEO FRAME SYNCHRONIZER FOR OBTAINING CLEAR DIGITAL VIDEO HAVING NO VARIABLE DELAY

摘要

PROBLEM TO BE SOLVED: To process a data frame sequence during synchronization loss by monitoring an input data frame, giving the pre-synchronous loss input data of an input data frame to a data compressor of an encoder before the synchronization loss and then giving the substitute data to the data compressor synchronously with the input of the pre-synchronization loss when the synchronization loss is detected. SOLUTION: An input video processor 125 gives a control signal SYNC-LOSS, etc., to a formatter 135, when a start (SAV) and/or end (EAV) sequence of an active video field is not detected at the time estimated. The input data are given to a buffer 130 regardless of a synchronous loss declaration. Receiving the signal SYNCH-LOSS, the formatter 135 gives a control signal to the buffer 130 and starts a switch 140. The switch 140 selects the input data 141, a black video 142 or a null video 143 and gives the output data to a data compressor 150.