A device for generating a radiographic image using a radiographic intensity distribution image, comprising: an imaging section, a drive section and a processing section, wherein the imaging section comprises a radiation source, a grating section and an image detection unit; the radiation source is configured to irradiate radiation towards the grating section; the image detection unit is configured to acquire a plurality of the intensity distribution images by detecting the radiation that has penetrated the grating section at given time intervals; the grating section has at least one grating that applies a periodic intensity modulation to the intensity distribution image; the grating has a periodic structure; the drive section is configured to move the grating in a direction that crosses an advancement direction of the radiation; the processing section comprises a ROI pixel value acquisition section, an elliptical locus determination section, an angle region image acquisition section and a radiographic image computation section; the ROI pixel value acquisition section is configured to acquire a first ROI pixel value of a first region of interest within the intensity distribution image and a second ROI pixel value of a second region of interest within the intensity distribution image; one of the first and second regions of interest is set to be at a position, or vicinity thereof, where a phase difference in the intensity modulation period, with respect to the other region of interest, becomes π/2; the elliptical locus determination section is configured to determine an elliptical locus that is obtained by plotting the first and second ROI pixel values for each of the intensity distribution images; the angle region image acquisition section is configured to obtain K angle region images using the intensity distribution images corresponding to at least k angle regions that have been obtained by dividing the elliptical locus for each given angle; the radiographic image computation section is configured to generate the radiographic image using the k angle region images; and k is an integer of three or more. an imaging section, a drive section and a processing section, wherein the imaging section comprises a radiation source, a grating section and an image detection unit; the radiation source is configured to irradiate radiation towards the grating section; the image detection unit is configured to acquire a plurality of the intensity distribution images by detecting the radiation that has penetrated the grating section at given time intervals; the grating section has at least one grating that applies a periodic intensity modulation to the intensity distribution image; the grating has a periodic structure; the drive section is configured to move the grating in a direction that crosses an advancement direction of the radiation; the processing section comprises a ROI pixel value acquisition section, an elliptical locus determination section, an angle region image acquisition section and a radiographic image computation section; the ROI pixel value acquisition section is configured to acquire a first ROI pixel value of a first region of interest within the intensity distribution image and a second ROI pixel value of a second region of interest within the intensity distribution image; one of the first and second regions of interest is set to be at a position, or vicinity thereof, where a phase difference in the intensity modulation period, with respect to the other region of interest, becomes π/2; the elliptical locus determination section is configured to determine an elliptical locus that is obtained by plotting the first and second ROI pixel values for each of the intensity distribution images; the angle region image acquisition section is configured to obtain K angle region images using the intensity distribution images corresponding to at least k angle regions that have been obtained by dividing the elliptical locus for each given angle; the radiographic image computation section is configured to generate the radiographic image using the k angle region images; and k is an integer of three or more.