Figure 4

Removal of ring artifacts from the micro-CT and dental-CT images of an animal bone. (a) Uncorrected bone image from micro-CT machine, (b-e) corrected images by using the MWPN (L _max = 1, k ₀ = 5.10, T _HN = 0.10 and N = 2), WF (L = 4, wname='db42' and σ = 10.0), RCHT (W = 125 and T = 0.0025), and RCP methods, respectively. (f-h) Effect of pre-correction on the WF, RCHT and RCP methods. Corrected images by using the WF (L = 2, wname='db41' and σ = 0.5), RCHT (W = 125 and T = 0.0005), and RCP methods applying on the pre-corrected image are displayed in (f-h), respectively. (i) Uncorrected bone image from dental-CT machine, (j-m) corrected images by using the MWPN (L _max = 5, k ₀ = 5.10, T _HN = 0.10 and N = 8), WF (L = 5, wname='db42' and σ = 10.5), RCHT (W = 125 and T = 0.0023), and RCP methods, respectively. (n-p) Applying correction on the pre-corrected image by using the WF (L = 5, wname='db42' and σ = 3.5), RCHT (W = 125 and T = 0.0019), and RCP methods, respectively. The window settings for (a-h) are 'C/W = 0.4132/0.2994' and that for (i-p) are 'C/W = 0.4714/0.1998'.