Hi all,<div><br></div><div>I have a deformable registration algorithm implementing by deriving a filter from itk::PDEDeformableRegistrationFilter and a function from itk::PDEDeformableRegistrationFunction. I use it alongside itk::MultiResolutionPDEDeformableRegistration and itk::RecursiveMultiResolutionPyramidImageFilter to accomplish multi-resolution registration with three levels.</div>
<div><br></div><div>The numerical stability of my deformable registration method's regularization is dependent on the image spacing. For images with higher spacing, I can use larger timesteps without losing accuracy. So, I would like to make the registration run faster by using larger timesteps at the first registration levels.</div>
<div><br></div><div>Is there a particular reason why there is no way to specify different timesteps for each level in itk::MultiResolutionPDEDeformableRegistration?</div><div><br></div><div>The API could be similar to that for the number of iterations:</div>
<div><meta http-equiv="content-type" content="text/html; charset=utf-8"><span class="Apple-style-span" style="font-family: Geneva, Arial, Helvetica, sans-serif; font-weight: bold; white-space: nowrap; -webkit-border-horizontal-spacing: 2px; -webkit-border-vertical-spacing: 2px; font-size: medium; ">virtual void <a class="el" href="http://www.itk.org/Doxygen318/html/classitk_1_1MultiResolutionPDEDeformableRegistration.html" style="color: rgb(26, 65, 168); text-decoration: none; font-weight: bold; ">itk::MultiResolutionPDEDeformableRegistration</a>< TFixedImage, TMovingImage, TDeformationField, TRealType >::SetNumberOfIterations(unsigned int <em>data</em>[] ) <code>[virtual]</code></span></div>
<div>In addition, we could add a function SetTimesteps that would input an array of timesteps, one for each level.</div><div><br></div><div>Is this something that people would find useful?</div><div><br>Thanks,<br><br>Danielle</div>
<div><br></div><div><br>-- <br>Danielle Pace, M.ESc.<br>Research and Development Engineer<br>Kitware Inc.,<br>North Carolina Office<div><br></div><div><a href="http://www.kitware.com" target="_blank">www.kitware.com</a></div>
<div>919-969-6990 X 319</div><br>
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