Ring artifact correction

Ring artifact suppression tool for tomograms

Ring artifacts on tomogram slices hinder image interpretation. They are caused by minor variation in the response from individual elements in a two dimensional (2D) X-ray detector. Polar space decreases the suppression complexity by transforming the rings on the tomogram slice to linear stripes. However, it requires that the center of rings lie at the origin of polar transformation. If this is not the case, all methods employing polar space become ineffective. We developed a method based on Gaussian localization of the ring center in Hough parameter space to assign the origin for the polar transformation. Thus, obtained linear stripes can be effectively suppressed by already existing methods. This approach functions automatically, avoids the need for assumptions and preserves fine details, all critical for synchrotron based nanometer resolution tomography.
USAGE:
*Convert the 3D data to 16bit sequential image slices with .tif extension and save them in one folder
*Insert your folder name with tif files below in the code, "kill_rings_V8_paralle.m":
imagepath = '/media/user/tifffiles-folder/';
*If the rings are centred, change
centered = 0; to centered = 1; (saves time) in "kill_rings_V8_paralle.m"

Please cite the paper if you use the code:
http://dx.doi.org/10.1063/1.4897441