Hi Kishore,<br>My images have resolution of 2 microns isotropic voxel size (typically brain MR images have resolution of 1 to 2 mm I suppose).....to load them into memory I would have to sub-sample them substantially, unfortunately there are some structures which are visible only at the highest resolution...I plan to deformably register<br>
all the images to an atlas.<br><br>I vaguely remember reading somewhere that ITK was designed to process volumes even when it was not possible to load the volume into memory...though I am not sure...<br><br>In case it is not possible what is the best approach (other than subsampling), for example would any of the following work :<br>
<br>a) Do overlapping block wise deformable registration and then apply some smoothing/regularization to the deformation field<br><br><br>b) In BSpline deformable registration for example, precompute the similarity measures in some neighborhood around gridpoints <br>
<br>or any other approach<br><br><br>Regards,<br>Somi<br><div class="gmail_quote">On Thu, Nov 19, 2009 at 12:00 PM, Kishore Mosaliganti <span dir="ltr"><<a href="mailto:kishoreraom@gmail.com">kishoreraom@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi Somi,<br>
<br>
I do not know the answer to your question but usually subsampling<br>
affects the final transform in a very small way and speeds up the<br>
convergence.<br>
<br>
Kishore<br>
<div><div></div><div class="h5"><br>
On Thu, Nov 19, 2009 at 11:01 AM, somi <<a href="mailto:seesomi@gmail.com">seesomi@gmail.com</a>> wrote:<br>
> Hi,<br>
> Is there a way in ITK to perform deformable registration between two volumes<br>
> if the volumes are very large and cannot be loaded into memory ?<br>
><br>
> Regards,<br>
> somi<br>
><br>
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