| 摘要 |
A comb filter filters the luminance signal and a difference signal indicative of the difference in signal content between two sequential lines. A low-pass filter furnishes a low frequency luminance signal having only the low frequency components of the luminance signal. The low frequency signal is applied to a horizontal aperture correction circuit which furnishes substitute high frequency signals. The low frequency luminance signal and the substitute high frequency signals are applied to one input of a fade-in fade-out circuit whose other input receives the luminance signal. The ratio of signals at the output of the fade-in fade-out circuit is controlled by a correlation signal derived from the difference signal. In the digital embodiment, the fade-in fade-out circuit receives the luminance signal and the substitute high frequency signals only and the low frequency luminance signal is added to the output of the fade-in fade-out circuit. The chrominance signals are derived by synchronous detection from the difference signal.
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