An image processing device and the like acquire a first image that corresponds to the wavelength band of white light and a second image that corresponds to a specific wavelength band, and appropriately set the display mode of an output image. The image processing device includes: a first image acquisition section (320) that acquires a first image, the first image being an image that includes an object image including information within a wavelength band of white light； a second image acquisition section (330) that acquires a second image, the second image being an image that includes an object image including information within a specific wavelength band； a candidate attention area detection section (341) that detects a candidate attention area based on a feature quantity of each pixel within the second image, the candidate attention area being a candidate for an attention area； a reliability calculation section (342) that calculates reliability that indicates a likelihood that the candidate attention area detected by the candidate attention area detection section is the attention area； and a display mode setting section (343) that performs a display mode setting process that sets a display mode of an output image corresponding to the reliability calculated by the reliability calculation section.
