[Insight-users] warping a clound of points when the target landmarks form a straight line

[Ramón Casero Cañas]

Hi,

I have a cloud of 3D points in space from a sampling of a bent cylinder.

I would like to straighten up said cylinder.

I have tried the ITK kernel transforms

    itk::ElasticBodySplineKernelTransform
    itk::ElasticBodyReciprocalSplineKernelTransform
    itk::ThinPlateSplineKernelTransform
    itk::ThinPlateR2LogRSplineKernelTransform
    itk::VolumeSplineKernelTransform

saying that I want to map the curved medial line of the cloud of points 
(source landmarks) to a straight line (target landmarks).

However, all kernel transforms suffer from the limitation that they can 
only map points to the space spanned by the target landmarks.

That is, if the target landmarks form a straight line, the bent cylinder 
will be transformed to a straight line, not a straight cylinder.

Then I looked into using

    itk::BSplineDeformableTransform

but it doesn't seem to operate on a sparse set of landmarks, but on a 
regular mesh.


I have been searching online, and although there seems to be a 
cornucopia of methods to deform meshes, I couldn't find anything that 
seems readily implemented.

Is there a more or less simple way to solve this problem in ITK?

Best regards,

Ramon.


-- 
Dr. Ramón Casero Cañas

Computational Biology
Department of Computer Science
University of Oxford
Wolfson Building, Parks Rd
Oxford OX1 3QD

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