1. An image processing apparatus, comprising: at least one circuit configured to: perform a process of using color information in an input image signal to determine at least one candidate color region for use as an extraction color region by assigning every pixel or every block including a predetermined number of pixels in a predetermined image region to any one of a plurality of color regions and determining the at least one candidate color region on the basis of a frequency of each color region of the plurality of color regions; prompt a user to select an extraction color region in case a plurality of color regions are determined as the candidate color region; and perform image processing on at least one of the extraction color region of the input image signal and the remaining region of the input image signal excluding the extraction color region, to obtain an output image signal.