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<DIV><FONT face=Arial size=2>Hi all,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>when using the ImageToImage metrics (for example
</FONT></DIV>
<DIV><FONT face=Arial size=2>itk::MutualInformationImageToImageMetric), one
needs to provide</FONT></DIV>
<DIV><FONT face=Arial size=2>a spatial transformation, which is used by the
metric (for example to compute derivatives)</FONT><FONT face=Arial
size=2>.</FONT></DIV>
<DIV><FONT face=Arial size=2>My question is what about using a deformation field
(WarpImageFilter) as "transformation", </FONT></DIV>
<DIV><FONT face=Arial size=2>what may also be seen as the more general
approach???</FONT></DIV>
<DIV><FONT face=Arial size=2>One could consider the deformation field as a
transformation as well (with much more parameters, of course)</FONT></DIV>
<DIV><FONT face=Arial size=2>and calculate derivatives </FONT><FONT face=Arial
size=2>with respect to the deformation values (to control for example some
registration process).</FONT></DIV>
<DIV><FONT face=Arial size=2>Is the framework open for this and how expensive
would it be to implement such an approach (not only complexity</FONT></DIV>
<DIV><FONT face=Arial size=2>of calculation but also effort of
implementation)?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks for any suggestions,</FONT></DIV>
<DIV><FONT face=Arial size=2>Markus</FONT><FONT face=Arial
size=2> </FONT> </DIV></BODY></HTML>