| 摘要 |
Artifacts result from unrecorded, stochastically distributed relative movements of a radiation source, radiation detector, and/or the object during a scanning process. The artifacts occur when a three-dimensional image dataset is reconstructed from two-dimensional projection images acquired from different projection directions. Geometric parameters describing an acquisition geometry for each projection image are taken into account during the reconstruction. The correction includes filtering the projection images to obtain a set of filtered first intermediate images. A set of second intermediate images are formed by filtering the projection images with a second filter. A three-dimensional reconstruction dataset is constructed from the filtered projection images filtered by way of the second filter, and forward projection is applied in the projection directions. Displacement information is determined for each projection direction by comparing the respective first intermediate image with the second intermediate image, and the geometric parameters are adjusted as a function of the displacement information.
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