| 摘要 |
PURPOSE:To obtain appropriately desired effects by providing a gain control means for controlling the luminance and the amplitude of a chrominance signal and a control signal generating means for controlling the amplitude of the gain control means on one screen and changing the picture state at desired positions on the same screen. CONSTITUTION:When the center of a screen where main picture exists is screened clearly a parabolic waveform, that is, a control signal S1 is generated in accordance with horizontal and vertical synchronizing signals H and V inputted to a control signal generating means 3, and inputted to a gain control means 2, which amplifies a luminance signal Y1 for passing through a clamp circuit 7 and having a reproduction DC level by center on the same screen with respect to horizontal and vertical directions in accordance with the signal S1, and outputs it from a terminal 18. Simultaneously a chrominance signal C2 only whose center on the same screen is amplified is outputted from a terminal 19. When a picture is formed on the basis of the output, so-called spotlighted picture effects where the center is emphasized can be obtained.
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