Image processing depends on whether the technique used is screen-film mammography or digital mammography. In the first technique, the images are obtained as photographic films, whereas in the second technique, digital files are viewed directly on a computer screen.
Screen-film mammography uses a single-emulsion X-ray film, which acts as the image receptor as well as displaying the image. The film emulsion captures and stores the latent image. Also after processing, it displays the permanent image of the film. The phosphor on the X-ray film stores the energy from X-ray photons; after processing through the developing technique, it forms a permanent image on the X-ray film.
In digital mammography the film is replaced by detectors, which are used to acquire a digital image. The energy of the photons is converted into an electrical signal and then assigned a digital number, which forms the mammographic image.
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