VIDEO SIGNAL PROCESSING CIRCUIT

摘要

PROBLEM TO BE SOLVED: To prevent the signal level of an output signal from being changed from the signal level of an input signal without increasing the scale of the circuit by adding output signals outputted from R, G and B signal amplifier means and dividing the added signal by the value of a power of 2 so that the sum of multiplication coefficients for the R, G and B signal amplifier means coincides with the divided division coefficient. SOLUTION: An R signal inputted to the R signal input terminal 10 of the video signal processing circuit is amplified by an R signal amplifier circuit 13 so that its signal level is amplified to 19 times. Similarly a G/B signal inputted to a G/B signal input terminal 11/12 is amplified by a G/B signal amplifier circuit 14/15 so that its signal level is amplified to 38/7 times. These multiplication coefficients are calculated based on a prescribed mathematical expression. These R, G and B signals multiplied by integers are added by an adder 16 and the added signal is inputted to a division circuit 17. The circuit 17 divides the inputted signal by 64 to obtain a Y signal. The obtained Y signal is outputted from an output terminal 18 to the outside.