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Original Shepp–Logan phantom (Shepp & Logan, 1974 ▶). The grey scale has been adjusted to make the features in the ellipse discernible. In this way the background (pixel value = 0.0) and the ellipse contour (pixel value = 2.0) are saturated. The dotted line shows the position of the line profiles in Figs. 6 ▶ and 7 ▶. The dashed square delimits the area used for the histograms shown in the same figures.
