Possibly implement "geometric" based jacobian calculation

[gdevenyi]

ANTs has a "geometric" jacobian implementation, which computes the jacobian based on the change in volume of a tetrahedra centered at each voxel.

https://github.com/ANTsX/ANTs/blob/master/Utilities/itkGeometricJacobianDeterminantImageFilter.hxx

https://github.com/ANTsX/ANTs/blob/master/Examples/CreateJacobianDeterminantImage.cxx

[gdevenyi]

Related paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2823935/

[m-pilia]

Thanks for the suggestion! I had not seen that paper before, and it seems an interesting approach. In this context it would take some additional effort to implement, however, because the tricky part is to get a good cost function for gradient descent. It is an interesting possibility, however I have little time budget for disptools nowadays, so I am not sure it is something I can tackle in the short term.