Abstract: A system for obtaining an image includes a processor for receiving a projection image, processing the projection image to obtain a filtered image, applying a first factor for the projection image to obtain a first weighted image, applying a second factor for the filtered image to obtain a second weighted image, and obtaining a corrected image using the first and second weighted images, and a medium for storing the corrected image. A method of processing an image includes receiving a projection image, processing the projection image to obtain a filtered image, and determining a corrected image by applying a first factor for the projection image and applying a second factor for the filtered image. A method for obtaining an image includes determining a factor, using the factor to control a radiation source, and using the factor to reduce noise in an image generated using the radiation source.

Abstract: A method is disclosed for reconstructing image data of an examination subject from measured data, wherein a series of measured data sets has previously been acquired during a relative rotational movement between a radiation source of a computed tomography system and the examination subject and the measured data sets relate to the same section of the examination subject at succeeding instants in time. In at least one embodiment, first image data is reconstructed in each case from the measured data sets such that a series of first image data is available. A change variable indicating a change over time within the series of first image data is determined, and a distinction is made between different components of the examination subject in the first image data with the aid of the change variable. This distinction is used for beam hardening correction in an iterative algorithm for calculating enhanced image data.