There is provided an image processing apparatus that includes an ambient-light image obtaining section, a cumulative image generation section, and a high-quality image generation section. The ambient-light image obtaining section obtains an ambient-light image in a first time range, the ambient-light image being an image of an object captured with a predetermined exposure time. The cumulative image generation section generates a cumulative image in a second time range, the cumulative image being obtained by cumulative addition of each pixel value in a plurality of images, the plurality of images being of the object sequentially captured with the predetermined exposure time. The high-quality image generation section generates a high-quality image, the high-quality image being obtained by subtracting a pixel value in the ambient-light image from a corresponding pixel value in a normalized image, the normalized image being the cumulative image normalized based on a total sum of the exposure time.