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<DIV><FONT face="Bookman Old Style">Hi,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">I use the example located in
ITK-2.6\Examples\Segmentation\ShapeDetectionLevelSetFilter.cxx. When I run this
example I want to visualize the result of fast marching after each iteration. So
I add a observer to observe the iterationEvent of fast marching filter. I
set the speed of fast marching to 1.0 and the initial distance to -20. My image
is 256x256x48 and spacing is 1x1x3. I have three problems.</FONT></DIV>
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<DIV><FONT face="Bookman Old Style">1. I add the observer:
fastMarching->AddObserver(itk::IterationEvent(),
this->fastMarchingObserver), but the fastMarching does not invoke the
itk::IterationEvent. I add observer to shapeDetectionLevelsetFilter and it does
invoke this event. Why does fast marching not invoke this event?</FONT></DIV>
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<DIV><FONT face="Bookman Old Style">2. Because I cannot observer the
IterationEvent of the fast marching, I add a observer to observe the EndEvent of
fastmarching. After the fast marching end I visualize the result of
fast marching in traversal, sagital and coronal slices. The result in traversal
is a round, but the results in sagital and coronal are ellipse. I guess the
results should be round in three slices. Is it caused by
different spacing?</FONT></DIV>
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<DIV><FONT face="Bookman Old Style">3. I vusualize the result of each iteration
and stop it when the front come to the boundary. However ,I do not know how to
stop it. I intend to add a observer to observe the IterationEvent of
ShapeDetectionLevelSetFiler.After each iteration the observer determine if stop
the iteration. Which method should I call to stop the iteration?</FONT></DIV>
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<DIV><FONT face="Bookman Old Style">Any suggestion would be greatedly
appreciated!</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Regards,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Yixun Liu</FONT></DIV></DIV></BODY></HTML>