[Insight-users] Registration and Spacing : Bug

[Luis Ibanez]

Hi Michael, Carolyn

We were finally able to duplicate the problem you both
reported concerning the registration of image data with
non-unit spacing.

http://www . itk . org/pipermail/insight-users/2003-July/004215 . html
http://www . itk . org/pipermail/insight-users/2003-July/004314 . html

Using a simple registration case with translation transform,
we found that a very small spacing causes the optimizer to
become erratic.

We are tracking this problem in order to find a fix.

Our guess is that the spacing is not correctly considered
when computing the metric derivatives in the registration
method. A bug report has been filed in GNATS.


  Thanks for pointing this out.


     Luis