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<BR> Ok, thank you very much Luis.<BR>
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Date: Tue, 14 Jul 2009 12:43:23 -0400<BR>Subject: Re: [Insight-users] RigidTransform vs AffineTransform?<BR>From: luis.ibanez@kitware.com<BR>To: manueldavid.tabas@hotmail.es<BR>CC: insight-users@itk.org<BR><BR>David,<BR><BR>Yes, there are differences between the Similarity and Affine Transforms.<BR><BR>The Similarity Transform does: Translation, Rotation and Uniform Scaling<BR><BR>The Similarity Transform does *not* do Shearing, and it can not do <BR>non Uniform scaling (e.g. scale X by 5 and scale Y by 7 ).<BR><BR><BR> Luis<BR><BR><BR>--------------------------------------------------------------------------------------------------<BR>
<DIV class=EC_gmail_quote>On Tue, Jul 14, 2009 at 12:33 PM, Manuel David Tabas Calle <SPAN dir=ltr><<A href="mailto:manueldavid.tabas@hotmail.es">manueldavid.tabas@hotmail.es</A>></SPAN> wrote:<BR>
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<DIV> <BR>and what about Similarity2dTransform and AffineTransform??<BR> <BR>what are teh differences??<BR><BR>Thanks!<BR> <BR>
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Date: Tue, 14 Jul 2009 12:02:21 -0400<BR>From: <A href="mailto:luis.ibanez@kitware.com">luis.ibanez@kitware.com</A><BR>To: <A href="mailto:mort.motes@gmail.com">mort.motes@gmail.com</A><BR>CC: <A href="mailto:insight-users@itk.org">insight-users@itk.org</A><BR>Subject: Re: [Insight-users] RigidTransform vs AffineTransform?
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<DIV class=h5><BR><BR><BR><BR>Hi Motes:<BR><BR><BR> A Rigid Transforms is not<BR> just an Affine centered Transform.<BR><BR><BR>1) A Rigid Transform supports:<BR> Translations and Rotations<BR><BR>2) An Affine Transform supports:<BR> Translations, Rotations, Scaling and Shearing.<BR><BR><BR>In ITK, both the Rigid and Affine transforms are "centered".<BR>Which means that you can specify what point of space should<BR>be used as the center of rotations.<BR><BR><BR>Yes, there is something unique that is accomplished by using<BR>a Rigid Transform:<BR><BR><BR> Managing Translations and Rotations, by only optimizing<BR> in an space of Six dimensions, instead of the space of <BR> 12 dimensions where you have to optimize an Affine Transform.<BR> (this for the case of 3D images).<BR><BR><BR><BR> Regards,<BR><BR><BR> Luis<BR><BR><BR>--------------------------------------------------------------------------------------------<BR>
<DIV>On Sun, Jul 12, 2009 at 3:14 PM, motes motes <SPAN dir=ltr><<A href="mailto:mort.motes@gmail.com">mort.motes@gmail.com</A>></SPAN> wrote:<BR>
<BLOCKQUOTE style="PADDING-LEFT: 1ex">In the itkSoftwareGuide an examples is walked through using a RigidTransform. But is a RigidTransform not just a centered AffineTransform? I am a bit confused that a RigidTransform exists, as I understand rigid and non-rigid are concepts that includes transforms. Something like:<BR><BR>Rigid:<BR> - Translation<BR> - Affine<BR><BR>Non-Rigid<BR> - BsplineDeformableTransform<BR><BR><BR>Or are there something unique about a RigidTransform that is not accomplished using eg. translation or Affine transforms?<BR><BR>_____________________________________<BR>Powered by <A href="http://www.kitware.com/">www.kitware.com</A><BR><BR>Visit other Kitware open-source projects at<BR><A href="http://www.kitware.com/opensource/opensource.html">http://www.kitware.com/opensource/opensource.html</A><BR><BR>Please keep messages on-topic and check the ITK FAQ at: <A href="http://www.itk.org/Wiki/ITK_FAQ">http://www.itk.org/Wiki/ITK_FAQ</A><BR><BR>Follow this link to subscribe/unsubscribe:<BR><A href="http://www.itk.org/mailman/listinfo/insight-users">http://www.itk.org/mailman/listinfo/insight-users</A><BR><BR></BLOCKQUOTE></DIV><BR><BR></DIV></DIV>
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Charlas más divertidas con el nuevo <A href="http://download.live.com/">Windows Live Messenger</A></DIV><BR>_____________________________________<BR>Powered by <A href="http://www.kitware.com/">www.kitware.com</A><BR><BR>Visit other Kitware open-source projects at<BR><A href="http://www.kitware.com/opensource/opensource.html">http://www.kitware.com/opensource/opensource.html</A><BR><BR>Please keep messages on-topic and check the ITK FAQ at: <A href="http://www.itk.org/Wiki/ITK_FAQ">http://www.itk.org/Wiki/ITK_FAQ</A><BR><BR>Follow this link to subscribe/unsubscribe:<BR><A href="http://www.itk.org/mailman/listinfo/insight-users">http://www.itk.org/mailman/listinfo/insight-users</A><BR><BR></BLOCKQUOTE></DIV><BR><br /><hr />Charlas más divertidas con el nuevo <a href='http://download.live.com' target='_new'>Windows Live Messenger</a></body>
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