Abstract: A method comprises: receiving computed tomography measurement data with sets of measurement values, wherein a set corresponds to a detector element readout of the measurement data including measurement values from at least two different x-ray spectra; determining an error estimate per set of measurement values; defining a replacement reference value per set of measurement values; applying a function that maps the measurement values to corrected values, the corrected values being between the mapped measurement value and the replacement reference value of the respective set, such that for larger errors the corrected value is closer to or at the replacement reference value and for smaller errors the corrected value is closer to or at the measurement value; and reconstructing computed tomography image data based on the corrected values.

Abstract: A method for movement compensation during CT reconstruction, comprises calculating slice images. The calculating slice images comprising: selecting an initial movement state; calculating a reference voxel position in relation to the initial movement state; calculating a column image position of a voxel; ascertaining a changed movement state of the voxel at the column image position; calculating a changed voxel position in relation to the changed movement state; calculating a changed image position of the voxel; and using an image value of the intermediate image at the changed image position for back projection to calculate the slice images.

Abstract: A method for the artifact correction of three-dimensional volume image data of an object is disclosed. In an embodiment, the method includes receiving first volume image data via a first interface, the first volume image data being based on projection measurement data acquired via a computed tomography device, the computed tomography device including a system axis, and the first volume image data including an artifact including high-frequency first portions in a direction of a system axis and including second portions, being low-frequency relative to the high-frequency first portions, in a plane perpendicular to the system axis; ascertaining, via a computing unit, artifact-corrected second volume image data by applying a trained function to the first volume image data received; and outputting the artifact-corrected second volume image data via a second interface.

Abstract: An embodiment of the invention relates to a method for calculating an image matrix size N for reconstructing image data of an examination subject from projection data. The method includes acquiring projection data obtained during a relative rotational movement between a radiation source of a computed tomography system and the examination subject; calculating the image matrix size N as a function of an extent of an axial field of view of the computed tomography system and a sharpness value in the image data to be reconstructed; and making the calculated image matrix size available to a reconstruction unit to reconstruct the image data from the projection data acquired.

Abstract: An embodiment of the invention relates to a method for calculating an image matrix size N for reconstructing image data of an examination subject from projection data. The method includes acquiring projection data obtained during a relative rotational movement between a radiation source of a computed tomography system and the examination subject; calculating the image matrix size N as a function of an extent of an axial field of view of the computed tomography system and a sharpness value in the image data to be reconstructed; and making the calculated image matrix size available to a reconstruction unit to reconstruct the image data from the projection data acquired.

Abstract: A method for the artifact correction of three-dimensional volume image data of an object is disclosed. In an embodiment, the method includes receiving first volume image data via a first interface, the first volume image data being based on projection measurement data acquired via a computed tomography device, the computed tomography device including a system axis, and the first volume image data including an artifact including high-frequency first portions in a direction of a system axis and including second portions, being low-frequency relative to the high-frequency first portions, in a plane perpendicular to the system axis; ascertaining, via a computing unit, artifact-corrected second volume image data by applying a trained function to the first volume image data received; and outputting the artifact-corrected second volume image data via a second interface.