| 摘要 |
PROBLEM TO BE SOLVED: To simplify the circuit configuration for color correction and also obtain an optimum luminance level over a wide range of an input video signal by means of gamma correction. SOLUTION: A matrix circuit 14 generates R, G, B signals from a received luminance signal Y are received color difference signals U, V, an RGB ratio detection circuit 20 detects a level ratio of the R, G, B signals, and a skin color correction section in a color correction circuit 22 applies skin color correction processing to the received R, G, B signals. Thus, the circuit configuration for skin color correction can be simplified more than that of a conventional circuit having required I and Q axis detection circuits. Furthermore, a gamma correction circuit 24 is provided with a logarithmic arithmetic section, a 1st multiplier section and an exponent arithmetic section. The logarithmic arithmetic section applies logarithmic arithmetic processing to the received R, G, B signals, the 1st multiplier section multiplies a gamma constantγwith an output of the logarithmic arithmetic section, and the exponent arithmetic section applies exponent arithmetic processing to an output of the 1st multiplier section so as to able to revise setting of the gamma constantγthereby optionally revising a gamma correction curve.
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