Sampled video signal generating device for improving deviation based on difference of circuit characteristics among channels

An improved video signal processing circuit (63) in the high quality television system for alternating-current driving a liquid crystal module (64) is disclosed. A reference signal is inserted into vertical blanking periods of a R signal by a reference signal generator (20) and switching circuit (4). The R signal in which the reference signal is inserted is converted into digital signals of n channels by an A/D converter (6). There exists difference in circuit characteristics among signal processing circuits for processing the respective digital signals. However, the signals signal-processed for each channel are supplied to microcomputer 21 through switching circuits (181-18n). Since the microcomputer 21 controls full scale level and offset level of D/A converters 91-9n and adders 111-11n, the deviations produced among sampled video signals due to difference in circuit characteristics among channels can be reduced.