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<div>Hello Wassim,</div>
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<div>The following SimpleITK Jupyter notebook may be of interest to you (uses the exhaustive optimizer as an initialization approach): https://github.com/InsightSoftwareConsortium/SimpleITK-Notebooks/blob/master/63_Registration_Initialization.ipynb. </div>
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<div>Based on your runtime of 5sec I suspect you are not using sampling when computing the metric. Possibly consider random or uniform sampling. There are cases where you can achieve a decent registration using less than 10% of the data. </div>
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<div> hope this helps</div>
<div> Ziv </div>
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<span style="font-weight:bold">From: </span>wassim bouzeid <<a href="mailto:abou_zeid_wassim@hotmail.com">abou_zeid_wassim@hotmail.com</a>><br>
<span style="font-weight:bold">Date: </span>Wednesday, May 25, 2016 at 10:05 AM<br>
<span style="font-weight:bold">To: </span>"<a href="mailto:community@itk.org">community@itk.org</a>" <<a href="mailto:community@itk.org">community@itk.org</a>><br>
<span style="font-weight:bold">Subject: </span>[ITK] Metric Evaluation<br>
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<div dir="ltr">Hi Everyone,<br>
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I want to explore the domain of an image metric by exhaustive search (moving the second image with respect to the first image from a negative position to a positive position) so I am using the example in the source code MeanSquaresImageMetric1.cxx on 2D images.
The time to compute the metric value for a specified parameters on these 2D images is approximately 0.02 sec. (PC with 32000 MB memory, and 1 cores @ 3201 MHz).
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When I am applying this example to 3D nifti images, the computation time of the metric value is large (more than 5 sec.).<br>
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Does anyone know how to speed up the computation time on 3D images without using an optimizer?<br>
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Thanks in advance.<br>
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Best,<br>
Sam<br>
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