Linear chromaticity conversion is used to perform color reproduction of a liquid crystal display (LCD) compatible with a cathode ray tube (CRT). An inputted signal is subjected to processing similar to processing used in the CRT display. A light source chromaticity conversion processing portion carries out a .gamma. correction to the signal in a .gamma. operation portion by using .gamma.1=.gamma.crt of the same nonlinear characteristics as the CRT, and performs an operation of a chromaticity conversion matrix in a matrix operation portion. An LCD inverse .gamma. correction portion uses .gamma.2 establishing .gamma._lcd=.gamma.lcd/.gamma.2=1 to perform an inverse .gamma. correction to the inputted signal. An LCD .gamma. characteristic operation portion performs a .gamma. correction using .gamma. characteristics of the LCD to the signal inputted from the LCD inverse .gamma. correction portion, outputs a picture signal, and causes an image to be displayed on the LCD.