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<DIV> Hi!<BR><BR> I commented days ago some possible
problems with this method. I've received some feedback about it,
but not sorted out yet!</DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>There is a whole review on this about a bug or bad
implementation as it was using truncation instead of rounding or flooring. Also
there was some discussion about making the transformation corned-based
or centre-based. I don't know which is the status of this in the current
version.</FONT><BR></DIV>
<DIV><FONT face=Arial size=2>My problem is that the same PointType
element is transformed to different IndexType elements in images that only
differ on the dimension (same SizeType and same SpacingType). I double-checked
the header files and everything is consistent.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Particularly, the size on the z axis is different
(one pixel distance) between a 3D image and the same frame in a 4D image. I
think the dimension should not affect in here.</FONT></DIV>
<DIV><BR> It seems that the truncation could be an issue, but as u said it
will affect the two images instead and not just one of them. Otherwise the
center-based vs corner-based problem is not a big deal
here.<BR><BR> What i don't really understand is what
TransformPhysicalPointToIndex does... as far as i understand it only should
divide each coordinate by the scaling, round or floor the value and
make the transformation from center-based<BR> coordinates to a corner-based
index count (which is mainly add the offset).<BR><BR> I'm just considering
doing this process by myself and see what happens.</DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Someone suggested something about the
"</FONT>loop unrolling in itk::ImageTransformHelper".</DIV>
<DIV><BR>Cheers<BR>David</DIV></BODY></HTML>