| 摘要 |
PURPOSE:To improve the S/N by dividing a video area containing recording video signals into plural block areas and then recording the information showing the level of the high band signal of each block to the PCM track of a video tape recorder VTR. CONSTITUTION:The recording luminance signal Y is added with the 1H-delayed luminance signal Yd delayed by a 1H-delay circuit 2 through an addition circuit 3. The the side band of these added signal is eliminated and furthermore they undergo the band limitation to 0.9-3MHz via a BPF 4. The high band luminance signal separated by the BPF 4 undergoes the detection of its amplitude higher than a fixed level via an amplitude detecting circuit 5. Then the luminance signal is binary-coded by a comparator 6 and this binary signal undergoes the logic operation via a logic memory circuit 8 to be arranged at every block. In other words, the circuit 8 outputs '1' when the highband luminance signal of each block is larger than a fixed level and then '0' when said luminance signal is smaller than the fixed level respectively. Then the luminance signal is mixed with the signal Y delayer by an addition circuit 9 by a fixed period.
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