[Insight-users] question on itkWarpImageFilter

[Gao, Yi]

Dear group,

I'm a little confused about the itkWarpImageFilter....

1. I understand that in computing the deformed (output) image, we
should go through the domain of the *output* image, and inversely
trace back (according to the deformation vector field) to find the
intensity in the input image.

2. However, on page 242 of the software guide, above equation 6.21, we
see that the deformation vector field (as a vector image) should have
the same size as the *input* image. So the deformation field is
defined on the domain of the *input* image.

3. Then, go back to item 1, how do we achieve the inversion of the
vector field so as it defines on the domain of the *output* image?

Is there anything I misunderstand? Thanks for any hint!

Best,
yi