<table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top" style="font: inherit;"><p>Hi Xianjun,</p>
<p>it may not be right but it is just what I am thinking.<br>
Could it be the reverse transform if you take the opposite offsets, i.e reverse_offset = -offset ?</p>
<p>Best,<br>
Willi</p>
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                                <span style="font-weight:bold;">From:</span>
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                            xianjun.sun.ext_CRC &lt;xianjun.sun.ext@united-imaging.com&gt;;                            <br>
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                                <span style="font-weight:bold:">To:</span>
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                            insight-users@itk.org &lt;insight-users@itk.org&gt;;                                                                                                     <br>
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                                <span style="font-weight:bold:">Subject:</span>
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                            [Insight-users] How to do reverse transformation of cubic Bspline-based FFD?                            <br>
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                                <span style="font-weight:bold;">Sent:</span>
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                            Thu, Nov 1, 2012 3:14:27 AM                            <br>
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<p class="MsoNormal"><span lang="EN-US" style='font-size:14.0pt;'>Hello everyone,</span></p> 

<p class="MsoNormal"><span lang="EN-US" style='font-size:14.0pt;'> &nbsp;</span></p> 

<p class="MsoNormal" style='margin-left:21.0pt;'><span lang="EN-US"
 style='font-size:14.0pt;'>I got offsets of the control points employed to
transform image I1 to image I2, now I want to get the reverse transformation.
How can I do it? Any hints or reference paper?</span></p> 

<p class="MsoNormal" style='margin-left:21.0pt;'><span lang="EN-US"
 style='font-size:14.0pt;'>Thanks a lot.</span></p> 

<p class="MsoNormal"><span lang="EN-US" style='font-size:14.0pt;'> &nbsp;</span></p> 

<p class="MsoNormal"><span lang="EN-US" style='font-size:14.0pt;'> &nbsp;</span></p> 

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