| 摘要 |
Color control apparatus for use in color video receiving apparatus of the type capable of receiving a color video signal which includes a VIR signal, the latter having at least a chrominance reference signal therein. A chrominance channel is provided for processing the chrominance component included in the color video signal. An extracting circuit connected to the chrominance channel separates burst and chrominance reference signals from the received color video signal. A predetermined parameter in the separated burst signal is detected, and a corresponding parameter in the chrominance reference signal is detected. A common amplifier is responsive to the detected parameters for producing an amplified control signal which, in turn, is supplied to an adjustable circuit so as to adjust a color characteristic of the processed chrominance component in accordance with the amplified control signal. The detected parameters may be the level of the respective burst and chrominance reference signals, which levels are detected by comparison with a reference level. The detected burst signal level thus is used in an automatic chrominance control circuit, and the detected chrominance reference signal level is used in a color saturation control circuit, both of these control circuits being connected with the common amplifier for controlling the color saturation level of a processed chrominance component. Also, the detected parameter may be the respective phases of the burst and chrominance reference signals with respect to a local oscillating signal used for demodulating the chrominance component. In that event, the detected burst signal phase and chrominance reference signal phase are used in automatic phase control and hue control circuits, respectively, both of these control circuits being connected to the common amplifier. In a preferred embodiment, the color control apparatus includes an ACC and a saturation control circuit connected to one common amplifier for controlling color saturation, and an APC circuit and a hue control circuit connected to another common amplifier for controlling the hue characteristic of the ultimately demodulated color signals.
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