[Insight-users] deformation field from image registration (beginner question)

[wenjia]

Hi, Ramesh,

I have tried DeformableRegistration8.cxx before. It can provide a deformation 
field and it works. I saved the field in .mhd format and opened it with paraview 
successfully.

To output a field in text format, you may modify relevant codes in 
DeformableRegistration8.cxx. The code for computing the field is from line 515 
to 526.

Cheers,
Wenjia Bai

insight-users-request at itk.org wrote:
> ------------------------------
> 
> Message: 2
> Date: Tue, 10 Jun 2008 15:13:00 -0500
> From: "Ramesh ITK" <itk.ramesh at gmail.com>
> Subject: [Insight-users] deformation field from image registration
> 	(beginner	question)
> To: insight-users at itk.org
> Message-ID:
> 	<4939af1b0806101313y217bbfb5k5dd5606eee169007 at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> I'm trying to obtain the deformation field between a fixed image and a
> moving image using ITK and I'm having trouble trying to read/view the output
> field.
> 
> The moving image is of a deformed object where different regions have
> different transformations (like in an inhomogeneous material).
> 
> I tried using the example code - DeformableRegistration5.cxx and the given
> data files (RatLungSlice1 & 2)
> It let me save the deformation field only in vtk or mhd/mha format.
> How do I obtain the vector of displacements over the region?
> 
> Paraview crashes when I try to open the mha file.
> When I try the mhd file it fails and gives the following message.
> *ERROR: In
> c:\berk\releasebuilds\paraview3\vtk\common\vtkDataArrayTemplate.txx, line
> 133
> vtkFloatArray (05B871A8): Unable to allocate 1858633728 elements of size 4
> bytes. *
> It also displays that the zrange is from -nan to nan
> 
> I also tried reading the *.raw  files using what was mentioned in
> http://www.itk.org/pipermail/insight-users/2003-December/005865.html but
> that didn't help much.
> 
> I'm not sure about the following things-
> Am I using the right example code to do what I am looking for?
> Does ITK give the vector displacement field for registration between two
> images (with different transformation matrices at different regions)?
> Can the displacement field be output directly as a text file instead of a
> visual format?
> 
> I'd appreciate it if someone could point me in the right direction.
> 
> Thanks,
> Ramesh