<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:DengXian;
panose-1:2 1 6 0 3 1 1 1 1 1;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Aptos;}
@font-face
{font-family:"\@DengXian";
panose-1:2 1 6 0 3 1 1 1 1 1;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
font-size:12.0pt;
font-family:"Aptos",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
code
{mso-style-priority:99;
font-family:"Courier New";}
p.xmsonormal, li.xmsonormal, div.xmsonormal
{mso-style-name:x_msonormal;
margin:0cm;
font-size:12.0pt;
font-family:"Aptos",sans-serif;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;
mso-ligatures:none;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:70.85pt 70.85pt 2.0cm 70.85pt;}
div.WordSection1
{page:WordSection1;}
--></style></head><body lang=DE link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='color:black;mso-fareast-language:EN-US'>Hi Huanyi,<o:p></o:p></span></p><p class=MsoNormal><span style='color:black;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black;mso-fareast-language:EN-US'>the issue is generated by a change introduced in python 3.8 on Windows.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black;mso-fareast-language:EN-US'>Simon already included a potential fix in the FirstCudaReconstruction.py example a while ago, see <a href="https://github.com/RTKConsortium/RTK/commit/abe956fbda210952ea3796d15e2077e6844fe1bd">https://github.com/RTKConsortium/RTK/commit/abe956fbda210952ea3796d15e2077e6844fe1bd</a><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><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Best,<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Moritz<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Von:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Rtk-users <rtk-users-bounces@creatis.insa-lyon.fr> <b>Im Auftrag von </b>Huanyi Zhou<br><b>Gesendet:</b> Mittwoch, 29. Oktober 2025 23:32<br><b>An:</b> Simon Rit <simon.rit@creatis.insa-lyon.fr><br><b>Cc:</b> rtk-users@openrtk.org; j_z_shen <j_z_shen@yahoo.com>; James Shen <jshen@neuraltrak.com>; Linxi Shi <linxit@neuraltrak.com><br><b>Betreff:</b> Re: [Rtk-users] RTK Python Wrapper—Missing CudaFDKBackProjectionImageFilter and Update Request<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='color:black'>Hi, Simon:<br><br>Thanks for the responding.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>I found the "</span><b><span style='color:#1F2328'><a href="https://github.com/RTKConsortium/RTK/actions/runs/18792156269/artifacts/4368557344"><span style='color:#1F2328'>WindowsWheel310-cuda124</span></a></span></b><span style='color:black'>" python wheel package from the link. </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:black'>But I got the following question:<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'><br>Here is what I did and the python package installed correctly:<br>Build conda env -> Install python=3.10 -> Install cuda toolkit = 12.4 -> pip install itk -> pip install itk_rtk_cuda124-2.7.0.post1-cp310-cp310-win_amd64.whl -> Install other dependencies<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>The function <b>CudaFDKBackProjectionImageFilter()</b> is wrapped. However, when I was trying to test the function: <br><br>I got this issue:<br>"<br>D:\Python_RTK_Code\20251006_RTK_Recon_Develop>python<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>Python 3.10.19 | packaged by Anaconda, Inc. | (main, Oct 21 2025, 16:41:31) [MSC v.1929 64 bit (AMD64)] on win32<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>Type "help", "copyright", "credits" or "license" for more information.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>>>> import itk<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>>>> from itk import RTK as rtk<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>>>> aa = rtk.CudaFDKBackProjectionImageFilter.New()<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>Traceback (most recent call last):<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "<stdin>", line 1, in <module><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\lazy.py", line 138, in __getattribute__<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> base.itk_load_swig_module(module, namespace)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 94, in itk_load_swig_module<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> itk_load_swig_module(dep, namespace)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 94, in itk_load_swig_module<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> itk_load_swig_module(dep, namespace)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 239, in itk_load_swig_module<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> load_module_needed_factories(name)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 390, in load_module_needed_factories<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> load_factories(needed_factories[name])<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 367, in load_factories<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> itk_load_swig_module(module_name, namespace)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 94, in itk_load_swig_module<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> itk_load_swig_module(dep, namespace)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 130, in itk_load_swig_module<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> l_module = loader.load(swig_module_name)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\base.py", line 289, in load<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> l_spec.loader.exec_module(l_module) # pytype: disable=attribute-error<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "<frozen importlib._bootstrap_external>", line 883, in exec_module<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> File "C:\Users\huany\anaconda3\envs\cuda124dev\lib\site-packages\itk\support\..\CudaCommonPython.py", line 10, in <module><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'> from . import _CudaCommonPython<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>ImportError: DLL load failed while importing _CudaCommonPython: The specified module could not be found."<br><br>To troubleshoot this issue, I used <i>Dependencies</i> to inspect the </span><code><span style='font-size:10.0pt;color:black'>_CudaCommonPython.pyd</span></code><span style='color:black'> file, but no missing DLLs were found. I’ve attached the <i>Dependencies</i> log output for your reference.<br><br>I'm wondering if it is still an installation issue?<br>I’d greatly appreciate any advice or insights you might have. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>Best Regards <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='color:black'>Huanyi <o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='color:black'><o:p> </o:p></span></p></div><div class=MsoNormal align=center style='text-align:center'><hr size=2 width="98%" align=center></div><div id=divRplyFwdMsg><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:black'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:black'> Simon Rit <<a href="mailto:simon.rit@creatis.insa-lyon.fr">simon.rit@creatis.insa-lyon.fr</a>><br><b>Sent:</b> Wednesday, October 29, 2025 3:13 AM<br><b>To:</b> Linxi Shi <<a href="mailto:linxit@neuraltrak.com">linxit@neuraltrak.com</a>><br><b>Cc:</b> <a href="mailto:rtk-users@openrtk.org">rtk-users@openrtk.org</a> <<a href="mailto:rtk-users@openrtk.org">rtk-users@openrtk.org</a>>; j_z_shen <<a href="mailto:j_z_shen@yahoo.com">j_z_shen@yahoo.com</a>>; Huanyi Zhou <<a href="mailto:hyzhou@neuraltrak.com">hyzhou@neuraltrak.com</a>><br><b>Subject:</b> Re: [Rtk-users] RTK Python Wrapper—Missing CudaFDKBackProjectionImageFilter and Update Request</span> <o:p></o:p></p><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><div><p class=MsoNormal>Hi Linxi,<o:p></o:p></p></div><div><p class=MsoNormal>The two version on pypi, cuda124 and cuda116, both have the same content. If you want a wheel that contains CudaFDKBackProjectionImageFilter, you'll have to download it from the CI until the next release. The wheels are available as artifacts in github actions if you're logged in GitHub. See <a href="https://github.com/RTKConsortium/RTK/actions/runs/18792156269">here</a> for the latest main build.<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 Wed, Oct 29, 2025 at 7:11<span style='font-family:"Arial",sans-serif'> </span>AM Linxi Shi <<a href="mailto:linxit@neuraltrak.com">linxit@neuraltrak.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><div><p class=xmsonormal><span lang=EN-US>Hi Simon,<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US>We’re a Silicon Valley startup building 3D image guidance for surgery.<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US>At a high level: our product uses RTK. We initially installed the precompiled package via:<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'>python -m pip install itk-rtk-cuda116</span><span lang=EN-US><o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US>Everything worked until we uncovered a quantitative mismatch in the reconstruction, which we traced to a missing filter-</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'>CudaFDKBackProjectionImageFilter</span><span lang=EN-US>-that (per your note on our issue <a href="https://github.com/RTKConsortium/RTK/issues/835" target="_blank">thread</a>) wasn’t included until <b>June 4</b> so it is confirmed that it is missing in our version.<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US>We see the <a href="https://docs.openrtk.org/en/latest/INSTALLATION.html" target="_blank">instructions</a> now reference <b>cuda124</b>, but we’re not sure whether the Python wrapper/CI has been updated to include this filter. Could you confirm if there’s an updated wrapper that contains </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'>CudaFDKBackProjectionImageFilter</span><span lang=EN-US>? If not, we’d appreciate guidance on the best workaround.<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US>We’ve been stuck for long. Thanks so much for your help on this.<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US>Best,<br>Linxi<o:p></o:p></span></p><p class=xmsonormal><span lang=EN-US style='font-size:11.0pt'> </span><span lang=EN-US><o:p></o:p></span></p></div></div><p class=MsoNormal>_______________________________________________<br>Rtk-users mailing list<br><a href="mailto:rtk-users@openrtk.org" target="_blank">rtk-users@openrtk.org</a><br><a href="https://www.creatis.insa-lyon.fr/mailman/listinfo/rtk-users" target="_blank">https://www.creatis.insa-lyon.fr/mailman/listinfo/rtk-users</a><o:p></o:p></p></div></blockquote></div></div></div></body></html>