Extract control points for elastic random deformations

🚀 Feature

Extract transformation parameters for random deformations

Motivation (and Pitch)

Like in @fepegar gist, we want to be able to observe the control points(xx, yy), as well as the deformation vectors u, v.

That being said, ideally I’ve been thinking about something like -

import torchio as tio

transform = tio.RandomElasticDeformation(...)
u, v = transform.get_deformation_vectors()
x, y = transform.get_control_points()

Alternatives

I’ve already seen that there is a get_params method in RandomElasticDeformation, but I think that it generates new parameters for each method call. am I right? This method seems to provide a solution for u, v but not x, y.

Additional context

I mainly wondered if I miss anything, I really went into the documentation, source code and the gist but wasn’t 100% sure the feature is really missing.

If it does miss, I would love to help with a pull request.

[YarivLevy81]

Thanks! good to know about the LPS orientation. I close this to not confuse anyone.

[fepegar]

Looks good to me 😃

Just one small comment. LPS orientation is because ITK uses that convention (which DICOM also uses). In e.g. the VTK world, the coordinates would be RAS (I think. Orientation stuff is confusing!).

Displacement at the borders are zero because of the locked_borders kwarg in RandomElasticDeformation.