1. An imaging device comprising: an image sensor that includes a color filter array in which normal image generation color filters and correction information generation color filters are placed in an array, the normal image generation color filters corresponding to three or more bands, and the correction information generation color filters differing in spectral sensitivity characteristics from the normal image generation color filters; and a digital processing circuit configured to: perform an interpolation process on pixel values obtained using the normal image generation color filters to generate a normal image in which pixel values of missing pixels are interpolated; perform a spectral estimation process based on pixel values obtained using at least the correction information generation color filters; perform a correction information generating process to generate correction information that corrects the pixel values of the normal image based on a spectral estimate value obtained by the spectral estimation process; and perform a correction process on the normal image based on the correction information to generate a corrected image, wherein the correction information generation process generates the correction information that corresponds to a plurality of pixel values of the normal image based on data of one spectral estimate value that is obtained from one pixel value during the spectral estimation process.