| 摘要 |
PURPOSE:To obtain a contour-corrected signal from which a base noise is removed through simple circuit constitution by allowing a signal circuit to perform a base noise clipping, the extraction of an upper and a lower contour corrected signal, the composition of the corrected signal nearly simultaneously. CONSTITUTION:A video signal supplied to an input terminal 31 is delayed by tau through a delay circuit 32 and applied to the base of a transistor (TR) 18. The signal is supplied to the bases of TRs 22 and 27 without changing in polarity. The composite signal of the original signal and 2tau-delayed signal is supplied to the bases of TRs 12 and 17 through a TR28. The circuit consisting of TRs 21, 22, and 27 obtains the upper-side contour corrected signal and the circuit of TRs 21, 22, and 27 obtains the lower-side contour corrected signal. Then, the TRs 12 and 22 operate differentially to conduct a current corresponding to the difference between both signals through resistances 16 and 26, so that the composite signal of the lower-side and upper side contour-corrected signals appears at an output terminal 30. |
