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<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>Hi, Luis and all
users:</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>I have done a little
performance testing between ITK2.0.0 and ITK1.8.0.</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2>Unfortunately, using ITK2.0.0, a registration work is about 20%
slower.</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>I don't know if
anyone else have experienced this.</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>Here is what I
did. My code is to do 3D image registration using
Mattes</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>metric, evolutionary
optimizer, and Versor3DTransform. For fixed 500</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>iterations, it took
60 seconds using ITK2.0.0, while it took 48 </FONT></SPAN><SPAN
class=687262221-25022005><FONT face=Arial size=2>seconds </FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>using ITK1.8.0.
These numbers are average of three runs with the same</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>two images on the
same machine under identical conditions.</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>This is just to post
a concern about the performance, and hopefully, it</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2>would not become a
trend for future release</FONT></SPAN><SPAN class=687262221-25022005><FONT
face=Arial size=2>. <SPAN class=687262221-25022005><FONT face=Arial
size=2>Usually, I would have to </FONT></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2><SPAN
class=687262221-25022005><FONT face=Arial size=2>iterate 10,000 times for a good
registration, </FONT></SPAN><SPAN class=687262221-25022005><FONT face=Arial
size=2>which is consistent with </FONT></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2><SPAN
class=687262221-25022005><FONT face=Arial size=2>what in Martin Styner's paper.
If my program were used in clinic, to let
</FONT></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2><SPAN
class=687262221-25022005><FONT face=Arial size=2>users wait
</FONT></SPAN></FONT></SPAN><SPAN class=687262221-25022005><FONT face=Arial
size=2><SPAN class=687262221-25022005>another </SPAN><SPAN
class=687262221-25022005><FONT face=Arial size=2>20% more time after a new
release, they probably </FONT></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2><SPAN
class=687262221-25022005><FONT face=Arial size=2>would rather
</FONT></SPAN></FONT></SPAN><SPAN class=687262221-25022005><FONT face=Arial
size=2><SPAN class=687262221-25022005>stay with the old version. That is
reality.</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2><SPAN
class=687262221-25022005></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial size=2><SPAN
class=687262221-25022005>Thanks for all the work to keep ITK
growing.</SPAN></FONT></SPAN><SPAN class=687262221-25022005><FONT face=Arial
size=2></DIV></FONT></SPAN>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2>Regards,</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2>George</FONT></SPAN></DIV>
<DIV><SPAN class=687262221-25022005><FONT face=Arial
size=2></FONT></SPAN> </DIV></BODY></HTML>