An image processing method includes: acquiring a compressed image; switching between a viewing mode and a save mode; in the viewing mode, displaying a first image on a display device and deleting the first image after displaying the first image, the first image being either the compressed image or a display-processed image that is generated based on the compressed image and represented by information of three or fewer wavelength bands; and in the save mode, generating, based on the compressed image, a second image represented by information of four or more wavelength bands, and saving the second image to a recording medium.