Michael:<br><br>Its simple. Derive it yourself :-)<br><br>For a centered transform (with parameters : C = Center, T= Translation. R= Rotation matrix.), given a point 'p'<br><br>TransformedPoint = R (p - C) + C + T
<br><br>Now if you want your own Center C', let's find the parameters R' and T'<br><br>R (p - C) + C + T = R' (p - C') + C' + T'<br><br>The result is<br> R' = R<br> T' = T + (C-C') - R (C-C')
<br><br>ie. You will contruct a new transform with the same rotation matrix, your center and the new translation is given by the above equation.<br><br>Hope this helps.<br>--<br>karthik<br><br><div><span class="gmail_quote">
On 11/16/07, <b class="gmail_sendername">Michael Schildt</b> <<a href="mailto:michael.schildt@ifn-magdeburg.de">michael.schildt@ifn-magdeburg.de</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Hello!<br><br>I got a rigid transform of an itk registration with a certain center of<br>rotation. But for further processing i need to use an other center. Is<br>it possible to recompute the matrix of a rigid/affine transform for a
<br>different center? Because, just setting a new center will result in a<br>different transform.<br><br>Here are some numbers:<br><br>TransformMatrix = -0.0183916 0.938708 -0.344223 -0.0411616 -0.3447<br>-0.93781 -0.998983
-0.00307907 0.0449783<br>Offset = 5.64609 -44.9436 -0.107986<br>CenterOfRotation = 1.09089 6.36365 -2.33333<br><br>I need to have a new center at [127.5, 127.5, 127.5].<br><br>Any hints are welcome :)<br><br><br>Best reguards,
<br> Michael Schildt<br>_______________________________________________<br>Insight-users mailing list<br><a href="mailto:Insight-users@itk.org">Insight-users@itk.org</a><br><a href="http://www.itk.org/mailman/listinfo/insight-users">
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