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Hi Karl,<br><br>
You may use the itk::BSplineUpsampleImageFilter.<br>
Look at the help of itk::BSplineUpsampleImageFilterBase. There it's
explained how it works.<br><br>
Regards,<br>
Stefan.<br><br>
<br><br>
<br>
<font size=3>At 08:46 23/07/04, Miller, James V (Research) wrote:<br>
<blockquote type=cite class=cite cite>I do not think ITK provides a
mechanism for increasing the number of <br>
control points in a B-spline grid. However, the mathematics of
B-splines<br>
do support this operation. There are formulas for adding a control
point<br>
to a B-spline that maintain the trace of the B-spline (shape of the<br>
B-spline).<br><br>
Any good book on B-splines will provide the formulas. <br><br>
Jim<br><br>
<br><br>
-----Original Message-----<br>
From: Karl Baum
[<a href="mailto:kgbaum@syr.edu" eudora="autourl">mailto:kgbaum@syr.edu</a>]<br>
Sent: Thursday, July 22, 2004 5:22 PM<br>
To: insight-users@itk.org<br>
Subject: [Insight-users] increasing bspline control point
density<br><br>
<br>
Hi,<br>
I am using BSplines to provide the transformations necessary for my<br>
registration. I would like to take an iterative approach where I
first do<br>
registration with a low control point density, and then use the results
as<br>
input to a registration with a higher control point density. The
issue I am<br>
facing at this point in time is how to initialize the parameters of
the<br>
second iteration with the results of the first iteration. In other
words I<br>
need to take the grid defined by the deformation coefficients of the
first<br>
iteration, and use it as input into the second. To do this I need
to<br>
calculate the starting deformation coefficients on the higher density
grid. <br><br>
Does itk provide anything to do this? I was unable to find
any<br>
documentation addressing this.<br><br>
Thanks,<br>
Karl<br><br>
<br>
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