Winston Lutz - Unity MR-Linac

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1

Hi everybody,
I have some trouble with the Winston Lutz test.
Currently, I’m trying to evaluate Winston Lutz images from the Unity MR-Linac. We don’t have any trouble to use pylinac with images from our differents Varian TrueBeams.
We have differents Pylinac versions on differents computers.
With Pylinac 2.0, the WL test, with Unity images, is running fine.
But…With Pylinac 3.0…
“ValueError: Unable to locate the BB. Make sure the field edges do not obscure the BB and that there is no artifacts in the images.”

I try to look on “change logs” but it seems that it is reaching the limit of my skills.
With Pylinac 2.0, it is possible to evaluate WL test, so I think (but maybe I’m wrong) that the images are OK.

Has anyone already faced this problem? Or have an idea about what to do ?
Thanks a lot !

WL.zip (5.27 MB)

2

I will answer myself. The problem is these lines:

if not is_near_center(bb_regionprops, self.dpmm, bw_bb_img.shape):
raise ValueError

I think that by commenting on them, the test no longer checks if the ball is in the center of the image. I don’t think that’s a problem. What do you think ?