| 摘要 |
PURPOSE:To decrease an H memory by providing a means to read two H memories to store alternately a color television signal continuously for four periods at the speed two times as much as the writing frequency, and a circuit to Y/C-separate from the output signal of two H memories. CONSTITUTION:An NTSC color television signal 1 is alternately written through an S/W1 to H memories 4 and 5 horizontally. The reading is executed two times as much as the writing clock frequency. Next, the output signal of H memories 4 and 5 is applied through an adder circuit 10 and an SW3, 12, SW3 and 13 to a subtracting circuit 7. Since the adder circuit 10 applies the signal which goes to be the relation delayed for one horizontal period, the color sub- carrier is eliminated and a luminance signal only is obtained. At the subtracting circuit 7, the signal of the color sub-carrier part is pulled out, supplied to a band-pass filter 8, supplies the chrominance components to a subtracting circuit 9, and the luminance signal is obtained. Since the band of the chrominance components is 1/6-1/3 of the band of the luminance signal, even when the band is a little narrower than that of the luminance signal, the picture quality deterioration is hardly detected, and consequently, the chrominance components are interporated by the same signal as the signal of the upper line.
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