[Insight-users] some questions on BSpline Registration

[Luis Ibanez]

Hi he smth,



ParaView will read MetaImage files directly.
They can be both scalar images and vector images.

1) If you save all your outputs from DeformableRegistration4
    as MetaImages you will be able to load them directly in
    ParaView. Simply use extensions .mhd in the filenames.

    For examples of visualization done with ParaView for
    deformable registration, you should look at the course
    on Image Registration Techniques at

       http://www.cs.rpi.edu/courses/spring04/imagereg/

    in particular to Lecture 25

      http://www.cs.rpi.edu/courses/spring04/imagereg/lectureDemons.ppt



2) You don't need to touch the origin and spacing when you
    use DICOM files. ITK will read those parameters directly
    from the DICOM files and will use them during the
    registration process.



3) The parameters of a BSpline deformable transform are the
    displacement values in all the nodes the grid. That becomes

      Number of Parameter = Number of Nodes * Image Dimension

     Please read the documentation of this transform

http://www.itk.org/Insight/Doxygen/html/classitk_1_1BSplineDeformableTransform.html



4) BSplines require 4 nodes in order to evaluate any internal
    point. Therefore your grid must have 3 extra nodes outside
    the extent of the image.  You can initialize the values of
    all the grid nodes to zero (zero displacement) at the
    moment of starting the registration.

    For details on the parameterization of this transform you should
    look at the course on Image Registration Techniques at

       http://www.cs.rpi.edu/courses/spring04/imagereg/

    in particular to Lecture 26

http://www.cs.rpi.edu/courses/spring04/imagereg/lectureBSplines.ppt



Regards,


    Luis



-----------------
he smth wrote:

> hi all,
> I have some questions in using DeformableRegistration4.
> 
> 1. I run the programe DeformableRegistration4.exe and get the
> deformable field. but then I have a question when viewing the result
> and the two input file(RatLungSlice1.mha and RatLungSlice2.mha) in
> paraview: can the result be accepted? I have save it to a .png file in
> the attachment. I hope that it is my fault and please tell me why.
> 
> 2. when I make it in use of dicom file registration, I am confused
> with the parameters of origin and spacing. please tell me how to set
> these values if any successful experience.
> 
> 3. what the parameters means? is it the motion field of each grid
> node? I have red the code for itkBSplineDeformableTransform, and found
> that the number of parameters is defined by the size of grid node.
> 
> 4. how to define the parameters of the BSplineDeformableTransform
> grid? In this example, we set gridSizeOnImage as 5 and gridBorderSize
> as 3, and so the size of grid node is 8*8.
> 
> thanks for any help!
> 
>