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jrkerns / pylinac

An image analysis library for medical physics
https://pylinac.readthedocs.io/en/latest/
MIT License
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CatPhan Find Origin Slice #312

Closed 4Dct closed 4 years ago

4Dct commented 4 years ago

Describe the bug Calling a set of CATPHAN503 images result in the failure to find the origin slice "ValueError: No slices were found that resembled the HU linearity module"

To Reproduce from pylinac import CatPhan503 cbct_folder = "mypath+file" mycbct = CatPhan503(cbct_folder) mycbct.analyze()

Expected behavior the images are noisy (streak artifact) but the CTP404 module is visible (see attachment) and should show a circle profile contains both low (<800) and high (>800) HU values

Screenshots CTP404 module slice Capture1

thanks for your help, and pylinac which is great

crcrewso commented 4 years ago

There are quite a few issues with this image that would prevent the pylinac module from detecting it. The high noise to contrast ratio would mess with the hu's and I can't even see the wires used for slice width. Do any of your other tools detect this as a ctp404 slice?

4Dct commented 4 years ago

Thanks for that, I have commercial software where the ctp404 slice can be manually selected.

Can the find origin slice be easily set manually. For the majority of the datasets I have, the keyslice can be found with pylinac.

crcrewso commented 4 years ago

Not at present, there's a lot of autodetection going on that tries to make it unnecessary. That panel is either in pretty bad shape or you're underdosing for the scan mode. I would say that such analysis is far enough from standard to require manual analysis with your existing solution.