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</o:shapelayout></xml><![endif]--></head><body lang=IT link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'>Thank you both for the help!<br>While I was reading Simon’s PhD student’s thesis I realized that stripes in my sinogram are actually horizontal and not random/pixel specific (rather projection specific).<br>They could represent a shift in gain response by the whole detector (there is an adaptive gain option in the acquisition that I must investigate), as projection by projection there is a tangible inconsistency in the average intensity value (see spikes in attached images as reference).<br><br>Again, thank you for your time, hope this might be of interest to you as well.<br><br>Gabriele<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b>Da:</b> Simon Rit <simon.rit@creatis.insa-lyon.fr> <br><b>Inviato:</b> giovedì 9 luglio 2020 16.06<br><b>A:</b> Samuel Gerber <samuel.gerber@kitware.com><br><b>Cc:</b> gabriele.belotti.bergamo@gmail.com; rtk-users <rtk-users@public.kitware.com><br><b>Oggetto:</b> Re: [Rtk-users] R: Ring Artifacts correction<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Excellent! Thanks for sharing.<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Thu, Jul 9, 2020 at 3:33 PM Samuel Gerber <<a href="mailto:samuel.gerber@kitware.com">samuel.gerber@kitware.com</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><p class=MsoNormal>This: <a href="https://github.com/InsightSoftwareConsortium/ITKRingArtifact" target="_blank">https://github.com/InsightSoftwareConsortium/ITKRingArtifact</a><o:p></o:p></p><div><p class=MsoNormal>might be of interest.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Best,<o:p></o:p></p></div><div><p class=MsoNormal>Sam<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Thu, Jul 9, 2020 at 9:30 AM Simon Rit <<a href="mailto:simon.rit@creatis.insa-lyon.fr" target="_blank">simon.rit@creatis.insa-lyon.fr</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><div><p class=MsoNormal>Hi Gabriele,<o:p></o:p></p></div><div><p class=MsoNormal>There is nothing readily available in RTK, sorry. A PhD student working with me worked on that but using python scripts, see his PhD thesis <a href="https://www.creatis.insa-lyon.fr/~srit/biblio/pivot2019.pdf" target="_blank">here</a>, chapter 7.<o:p></o:p></p></div><div><p class=MsoNormal>Simon<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Thu, Jul 9, 2020 at 2:57 PM <<a href="mailto:gabriele.belotti.bergamo@gmail.com" target="_blank">gabriele.belotti.bergamo@gmail.com</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Dear all,<br><br>I’m forwarding this email as the original had an image that was blocked from the mailing list due to overall size.<br><br>Gabriele</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><o:p></o:p></p><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0cm 0cm 0cm;border-color:currentcolor currentcolor'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b>Da:</b> <a href="mailto:gabriele.belotti.bergamo@gmail.com" target="_blank">gabriele.belotti.bergamo@gmail.com</a> <<a href="mailto:gabriele.belotti.bergamo@gmail.com" target="_blank">gabriele.belotti.bergamo@gmail.com</a>> <br><b>Inviato:</b> mercoledì 1 luglio 2020 11.51<br><b>A:</b> <a href="mailto:rtk-users@public.kitware.com" target="_blank">rtk-users@public.kitware.com</a><br><b>Oggetto:</b> Ring Artifacts correction<o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Dear Rtk users and developers,<br><br>I have a set of projections that suffer both from truncation and ring artifacts.<br>While for the first issue I’ve been fiddling with the --pad option to a satisfying result, I’m unsure what would be the best way to deal with the ring artifacts in RTK.<br>I’ll attach a screenshot of the sinogram showing evident strikes and an animated gif with the resulting reconstruction highlighting the concentric rings.<br><br>Thanks in advance for your help and input!<br><br>Gabriele Belotti</span><o:p></o:p></p></div></div><p class=MsoNormal>_______________________________________________<br>Rtk-users mailing list<br><a href="mailto:Rtk-users@public.kitware.com" target="_blank">Rtk-users@public.kitware.com</a><br><a href="https://public.kitware.com/mailman/listinfo/rtk-users" target="_blank">https://public.kitware.com/mailman/listinfo/rtk-users</a><o:p></o:p></p></blockquote></div></div><p class=MsoNormal>_______________________________________________<br>Rtk-users mailing list<br><a href="mailto:Rtk-users@public.kitware.com" target="_blank">Rtk-users@public.kitware.com</a><br><a href="https://public.kitware.com/mailman/listinfo/rtk-users" target="_blank">https://public.kitware.com/mailman/listinfo/rtk-users</a><o:p></o:p></p></blockquote></div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <o:p></o:p></p><div><div><p class=MsoNormal><span style='font-size:9.5pt;color:#888888'>Samuel Gerber<br>R&D Engineer<br>Kitware, Inc.</span><o:p></o:p></p></div></div></blockquote></div></div></body></html>