| 摘要 |
PURPOSE:To attain accurate color killer operation in a short time by comparing a reference value with a difference component of signals between the burst signal added synchronously in the level increasing direction and the signal extracting only the noise component by synchronous addition in the level cancelling direction so as to discriminate the presence of the burst signal. CONSTITUTION:The burst signal in the digital video signal is added synchronously in the level increasing direction of the burst signal over plural lines add a coefficient smaller than the unity is multiplied to the output. On the other hand, the burst signals are added synchronously in the level cancelling direction over plural lines and the difference component between the output and the multiplied output is compared with the reference value by a comparator circuit 29, the gate circuit 31 is controlled by making the color signal conductive or nonconductive in response to the result of comparison.
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