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Question Posted 03/13/19:
I am trying to understand some of the under the hood image processing that went to create the set of PET images that we are interested in working with. I am specifically wondering the intent and consequence of the function smooth via package XIDA and program cvt_ext_smooth is ?
Also if this package is open source and freely available.
we have thoroughly read page.
No references were made to XIDA (and its impact) and to some extent the use of “smooth” via XIDA seems conflicting with the description.
For our application, we do want to be certain that we understand all relevant processing that went in, hence the query.
I thank you for your time and efforts.
Response posted 03/19/19 by Robert Koeppe:
The intent of the smoothing is to put images from all scanners at the same resolution. Unsmoothed images are available if wanted. XIDA is not publically available, but any routine that smooths with a Gaussian function can be used. The resulting smoothed images are nominally at 8mm FWHM resolution. If there is considerably motion within the scan, the actual resolution could be lower, but that would be true of any PET image. E-mail koeppe@umich.edu if there are further questions.
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