<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=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I am interested in computing the 3D Radon transform of a data-set. This is as I understand it, inverse backprojection, and gives all the 2d projections (given angles phi, theta, psi) through a 3d image. Before re-inventing the wheel, I wanted to make sure I’m not missing any potentially re-usable elements of VTK for this problem. There is not a direct Radon transform in VTK, but in this paper (<a href="http://bioinformatics.oxfordjournals.org/content/14/2/212.abstract">http://bioinformatics.oxfordjournals.org/content/14/2/212.abstract</a>), the computation is elegantly broken down to a few steps that involve 2-D and 1-D FFTs, conversion to polar coordinates, and 3-d matrix transposition. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>My question to the VTK community (especially those more familiar with the API) is if there are any classes within VTK that would be useful in tackling this problem. Of course, if you have suggestions outside of VTK, those would be welcome as well. Unfortunately, based on my search so far, it seems that this will be something that needs to be written nearly from scratch. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks in advance for any insights,<o:p></o:p></p><p class=MsoNormal>Zamir<o:p></o:p></p></div></body></html>