A linear matrix circuit (6) generates a second R signal, a second G signal, and a second B signal by performing a matrix operation of correction coefficients of three rows and three columns composed of first to third correction coefficients, fourth to sixth correction coefficients, and seventh to ninth correction coefficients on a first R signal, a first G signal, and a first B signal that are generated by capturing an image of a subject by an imaging device. An R coefficient correction unit (13) performs correction such that, if a first difference value obtained by subtracting the first G signal from the first B signal exceeds a first threshold value, the first correction coefficient by which the first R signal is multiplied approaches one and the second and third correction coefficients by which the first G signal and the first B signal are multiplied, respectively, approach zero as the first difference value becomes larger.