Hello Ray,
The computation of the inverse of a BSpline transform is not implemented in ITK. The way to do it is (as discussed in this mailing list thread):
- Compute the deformation field corresponding to your BSpline
- Inverse your deformation field (there are multiple implementations in ITK to do this, such as 1 and 2). There is also a remote module that allows to compute this.
- Use this inverse transform after making sure that it has been sampled in the output image space
Hope this helps,
Francois