<br>Hi Sharath,<br><br>You are right in that it is not a good idea to take samples<br>from the entire 2000 x 2000 pixels image if we expect that<br>only a regions of 640 x 480 is going to match the Moving<br>image.<br><br>
The solution is to simply call <br><br> registration->SetFixedImageRegion( region )<br><br> and set "region" to the region of interest from the <br>2000 x 2000 image, where you anticipate to find matches<br>
for the moving image.<br><br><br>You will find examples on the use of <br><br> SetFixedImageRegion()<br><br>in the ITK software Guide<br><br> <a href="http://www.itk.org/ItkSoftwareGuide.pdf">http://www.itk.org/ItkSoftwareGuide.pdf</a><br>
<br>and most (if not all) the corresponding Image Registration<br>examples in <br><br> Insight/Examples/Registration<br><br><br><br><br> Regards,<br><br><br> Luis<br><br><br><br>---------------------------------------------------------------<br>
<div class="gmail_quote">On Fri, Jul 10, 2009 at 9:15 PM, Sharath Venkatesha <span dir="ltr"><<a href="mailto:sharath20284@yahoo.com">sharath20284@yahoo.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;">
<br>
Hi,<br>
<br>
I am working with images where the Fixed image is 2000*2000 pixels and the moving image is 640*480 (sub region of the fixed image). In all the Mutual Information metrics, the sampling is done on the Fixed image, and the transformed points are mapped on the moving image.<br>
<br>
I figured out that it is incorrect to sample the points randomly in the full fixed image ( as in my case, the moving image is a sub-part of the fixed image, and only 30-40% points were mapped), I used an approximate region of the fixed image from which sampling should be done. This has not improved the performance/accuracy of registration.<br>
<br>
I am thinking of sampling pixels from the moving image, and do a backward mapping to pixels in the fixed image. In this case, I think that almost all the points will be mapped, and hence the metric will be better.<br>
<br>
Do I need to change the functions in the respective files, or is there a simpler way to do this, or is already implemented?<br>
<br>
Thanks,<br>
<br>
Sharath Venkatesha<br>
<br>
<br>
<br>
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