Truncation artifact correcting method for computer tomographic picture, involves performing smoothing of signal of projection data row to reduce noise parts of signal, and calculating truncated part of row from smoothened signal

摘要

The method involves determining radiation (6) divergent from an X-ray radiation source (2), and adjusting projection images received from detectors (4, 4') by exploration. Smoothing of a signal of a projection data row by a digital polynominal filter e.g. Savitzky-Golay smoothing filter, is performed for reducing noise parts of the signal. A truncated part of the projection data row is calculated from the smoothened signal of the projection data row by an extrapolation procedure e.g. water cylinder extrapolation procedure.