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<P><FONT SIZE=2 FACE="Arial">Hello,</FONT>
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<P><FONT SIZE=2 FACE="Arial">I tried to implement a registration algorithm in the itk framework with a deformation field as a transform for a 256X256 2D image. </FONT></P>
<P><FONT SIZE=2 FACE="Arial">This field should be displacement vector for each pixel using all image pixels as grid points (i.e. 2*number of pixels degrees of freedom) and a gradient descent optimizer. It worked with the B-spline transform class, but it was really slow (2 minutes per optimizer iteration). I'm not sure if that was because B-spline class somehow makes the program compute splines for interpolation although there are no points in between the grid points. Does anyone know a faster way of implementing a deformation field?</FONT></P>
<P><FONT SIZE=2 FACE="Arial"> Thank you for your help,</FONT>
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<P><FONT SIZE=2 FACE="Arial">Andreas</FONT>
<BR><FONT SIZE=2 FACE="Arial"> </FONT>
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