1. An image processing device comprising: processing circuitry configured to detect an image region where an object exists as a target region on the basis of a second captured image, when a first captured image is a captured image obtained by selectively receiving a light of a first wavelength band, and the second captured image is a captured image obtained by selectively receiving a light of a second wavelength band, the captured images being obtained by capturing the object that is transparent for the light of the first wavelength band and is opaque for the light of the second wavelength band; and superimpose an outline of the object on the first captured image on the basis of information of the target region.