[Insight-users] Re: How the Bspline Warping Algorithm Works

[Luis Ibanez]

Hi Kevin,

The parameters of the BSpline transform *are* the coordinates of the
control points in the grid.

That is, if you have a BSpline grid with 3x5 points in 2D then you
have

           3  x  5  x 2   = 30 parameters in the Transform.



Please read the Doxygen documentation of this class:

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


" The parameters for this transform is N x N-D grid of spline
   coefficients. The user specifies the parameters as one flat array:
   each N-D grid is represented by an array in the same way an N-D image
   is represented in the buffer; the N arrays are then concatentated
   together on form a single array."

You may also find interesting to read the description of
this Transform, and its usage for Image Registration in the
ITK Software Guide


          http://www.itk.org/ItkSoftwareGuide.pdf



   Regards,


      Luis



=================
Kevin Ming wrote:
> Hi,
> 
> This maybe a rudimentary question but how does the bspline warping 
> algorithm in ITK utilize the parameters giving by the user to warp an 
> image?  How are they related to the control points?  What is the general 
> idea behind it?  I am somewhat familiar with the theories and 
> mathematics of bspline but am not sure how they can be applied to the 
> case of images, not to mention 3d images.
> 
> 
> Thank you,
> Kevin