Hi Aviv, Thank you very much for your help.<br><br>Jian<br><br><br>Date: Mon, 2 Jun 2008 22:02:09 +0300<br>
From: "Aviv Hurvitz" <<a href="mailto:aviv.hurvitz@gmail.com">aviv.hurvitz@gmail.com</a>><br>
Subject: Re: [Insight-users] Is there way to speed up<br>
cross-correlation based deformable registration?<br>
To: <a href="mailto:insight-users@itk.org">insight-users@itk.org</a><br>
Message-ID:<br>
<<a href="mailto:e25acca30806021202l50d68fa3j4a494ac5b4685b15@mail.gmail.com">e25acca30806021202l50d68fa3j4a494ac5b4685b15@mail.gmail.com</a>><br>
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<br>
See if you can use the elastix program (which is based on ITK code).<br>
<a href="http://elastix.isi.uu.nl/index.php" target="_blank">http://elastix.isi.uu.nl/index.php</a><br>
<br>
It has several speed improvements:<br>
1. You can specify samples.<br>
2. It utilizes the sparse Jacobian of the B-spline transform for faster<br>
computation of the metric gradient.<br>
3. You can use a multiple resolution strategy, both for the images and for<br>
the B-spline transform itself.<br>
<br>
- Aviv<br>
<br>
<br>
On Mon, Jun 2, 2008 at 9:20 PM, Jian Yang <<a href="mailto:yaland1977@gmail.com">yaland1977@gmail.com</a>> wrote:<br>
<br>
> Hi all,<br>
><br>
> I'm currently working on deformable registration of CT images. I'm using<br>
> cross-correlation (DeformableRegistration6.cxx) and mutual information<br>
> (DeformableRegistration15.cxx) metrics with a B-Spline Deformable Transform<br>
> in a 300*208*241 3D image.<br>
><br>
> It seems that the example DeformableRegistration15.cxx works much faster<br>
> than example DeformableRegistration6.cxx. I guess example<br>
> DeformableRegistration6.cxx is time consuming since it is performed on the<br>
> whole image. And the Mattes Mutual Information metric works faster because<br>
> it allows to take samples (SetNumberOfSpatialSamples) in the image instead<br>
> of taking all voxels. So, I am wondering is there way to do the same thing<br>
> in the cross-correlation metric to make it faster?<br>
><br>
> Thank you very much for your reply.<br>
><br>
><br>
> Best Regards,<br>
><br>
><br>
> Jian