PURPOSE: To allow more precise chroma-gamma-correction by constituting in such a way that gains of a chrominance signal processing circuit are changed in the line sequence in accordance with the level of luminance signal components included in an output of a solid-state image pickup element of a line sequential image pickup system, and chroma-gamma-correction is executed.
CONSTITUTION: A pair of gain variable resistance RA and RB and rA and rB with different resitance values are connected to amplifier circuits 25 and 26 through switches 25a and 26b which are switched by a horizontal synchronizing signal from a synchronizing signal generating circuit 6 so that gains can be changed at every scanning period in correspondence to color different signals 2R-G and 2B-G. A chroma-gamma-correction control circuit 28 detects a level of luminance signal components in an amplifier circuit 24, and changes gains of the amplifier circuit 25 in accordance with the detected level of luminance signal components. Namely, when the level of luminance signal components is high, gains of the amplifier circuit 25 are set small, and a coloring degree in a bright scane is reduced. When the level of luminance signal components is low, gain of the amplifier circuit 25 is set large, and difficult coloring in a dark scene is prevented.
KONUMA TAKEHIKO
EBATO TAKASHI
SAGIYA HIROSHI
KITANO YUTAKA
| JPS5017133A | 1975-02-22 | |||
| JPS4918424A | 1974-02-18 |