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Published 20 hours ago • verified publisher icon jrkerns

Catphan HU disc CNR error

Open brjdenis opened this issue 5 years ago • 2 comments

Hi there!

The evaluation of CNR for HU discs (CTP404) may be problematic. The bg_std (line 382) is calculated as the standard deviation of average pixel values over three background ROIs. Perhaps this should be an average of three standard deviations of pixels values inside the ROIs.

brjdenis avatar Oct 15 '20 09:10 brjdenis

Could you link to the line, please? The commits appear to have thrown off the line numbers.

jrkerns avatar Nov 20 '20 17:11 jrkerns

Hi. Sorry for the late reply. The line is this:

https://github.com/jrkerns/pylinac/blob/06a48d97e3650923e0f5929ae1dcb72c1562f958/pylinac/ct.py#L251

It may perhaps be better to have a mean of std values.

brjdenis avatar Dec 14 '20 17:12 brjdenis