Differences in the individual pixel response of detector elements introduce ring artifacts in tomographic images seriously degrading image quality. Removing or at least significantly reducing such artifacts is indispensable. In this paper an improved ring artifacts remover filter based on the approach of I. Sijbers and A. Postnov [1] is presented. The principal advantage and core characteristic of the proposed method is that it can be applied directly on images that have been already reconstructed, thus eliminating the need for additional imaging data like sinograms, flat fields and dark fields that are traditionally used for ring removal. The proposed method is computationally inexpensive and can be used even within established CT workflows or on past archived tomographic data.
