[Insight-users] [Community] Demons Deformable Registration and Paraview

[Matt McCormick]

Hi Tim,

The displacement fields output of ITK's deformable image registration
represent the displacement of a point in the FixedImage to a point in
the MovingImage.  Therefore overlaying the displacement field vector
glyphs on the FixedImage should give the correct visualization.  The
start of the arrow sits on its location in the input FixedImage, and
the tip of the arrow glyphs are directed towards where a given pixel
in the FixedImage will move to in the MovingImage.

Hope this helps,
Matt

On Mon, Oct 21, 2013 at 6:39 PM, Tim Bhatnagar <tim.bhatnagar at gmail.com> wrote:
> Hello all,
>
> Has anyone used Paraview to visualize Deformable Registration Displacement
> fields in Paraview? I am having trouble verifying what exactly paraview is
> showing me. A point (x,y,z) where I know a large y-deformation occurs does
> not exhibit that vector magnitude in Paraview, but it DOES seem to exist at
> a spatial coordinate that corresponds to where the large deformation ENDS
> (ie where the (x,y,z) point is located AFTER registration).
>
> Between this, and 'flipping' the x- and y- components of the vectors in the
> displacement field, I have managed to become very confused about the proper
> way to visualize the data.
>
> Note that after using WarpImageFilter with my registration-produced
> displacement field, I get the registered output I was looking for (yay!).
> It's just visualizing the proper deformation field for visual/qualitative
> figures is completely eluding me.
>
> Any help is greatly appreciated, though I feel like my emails in this
> user-list not up to par in terms of how I describe my problem, or the
> information I pass along is not enough to have an experienced ITKer chime
> in. If this is the case, please tell me what other info you need,as I'm
> happy to provide it.
>
> Alternatively, if it's best I address this to a Paraview-users community, I
> can try that. I just figured anyone who used Demons in ITK would most likely
> also visualize the field..
>
> Thanks,
> --
> Tim Bhatnagar
> PhD Candidate
> Orthopaedic Injury Biomechanics Group
> Department of Mechanical Engineering
> University of British Columbia
>
> Rm 5000 - 818 West 10th Ave.
> Vancouver, BC
> Canada
> V5Z 1M9
>
> Ph: (604) 675-8845
> Fax: (604) 675-8820
> Web: oibg.mech.ubc.ca
>
> _____________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Kitware offers ITK Training Courses, for more information visit:
> http://www.kitware.com/products/protraining.php
>
> Please keep messages on-topic and check the ITK FAQ at:
> http://www.itk.org/Wiki/ITK_FAQ
>
> Follow this link to subscribe/unsubscribe:
> http://www.itk.org/mailman/listinfo/insight-users
>
> _______________________________________________
> Community mailing list
> Community at itk.org
> http://public.kitware.com/cgi-bin/mailman/listinfo/community
>