Ohser, J.J.OhserSchladitz, K.K.SchladitzKoch, K.K.KochNöthe, M.M.Nöthe2022-03-032022-03-032005https://publica.fraunhofer.de/handle/publica/209424A spectral theory for constituents of macroscopically homogeneous random microstructures is developed and provided with a sound mathematical basis, where the spectrum obtained by Fourier methods corresponds to the angular intensity distribution of X-rays scattered by this constituent. It is shown that the fast Fourier transform applied to three-dimensional images of microstructures obtained by micro-tomography is a powerful tool of image processing. The applicability of this technique is demonstrated in the analysis of images of porous media.en519003006669journal article