Removal of ring artifacts in X-ray micro tomography using polyphase decomposition and spline interpolation

Micro computed tomographic images are often damaged by the so called ring artifacts. Ring artifacts are the concentric rings superimposed on the tomographic slices caused by the defective and non uniformly calibrated detector elements. Reduction of these artifacts is necessary for the post processing of the images. In this paper, a computationally efficient algorithm is developed to compensate for the ring artifacts. A simple high pass filter is employed to detect the isolated single ring positions. The polyphase decomposition is used to detect the weak but most difficult band rings. Finally, the correction is done using the spline interpolation technique. The performance of this proposed algorithm is evaluated with real micro-CT images and is compared with a well-known algorithm. Simulation results demonstrate superior performance of the proposed technique as compared to other technique reported in the literature.