Hi Martin,
In the lecture the 7dof is described; it is rigid body (rotation &
translation) plus global scaling (ie same scaling in all directions).
Cheers.
On Fri, 3 Dec 2004, Martin Kavec wrote:
> Thanks for the link, Christian.
>
> The whole lecture is really great. However, I did't find quite what I expected.
> I'll try to put what I am looking for in another words.
>
> I work on a quite difficult registration problem and I use FLIRT results as a
> refence. My implementation platform is ITK ( http://www.itk.org ) and my aim is
> to replicate, at the begining, FLIRT results. ITK implements three types of
> transformation for 3D registration: AffineTransform (DOF=12),
> Quaternian3DTransform (DOF=7) and Versor3DRigidTransform (DOF=6).
>
> So I was wondering what transforms FLIRT uses.
>
> Cheers,
>
> Martin
>
> Quoting "Christian F. Beckmann" <[log in to unmask]>:
>
> > Martin,
> >
> > the FSL course talk on registration etc covers this, see
> > http://www.fmrib.ox.ac.uk/fslcourse/lectures/flirt_fugue/s_1030xfm.htm
> >
> > cheers
> > christian
> >
> >
> >
> > On 3 Dec 2004, at 14:13, Martin Kavec wrote:
> >
> > > Hi.
> > >
> > > I am trying to figure out, what transform is optimized with
> > different
> > > DOFs in 3D registration. In DOF=12, I would guess, it is Affine
> > > transform.
> > > I am particularly interested in DOF=6, 7. I briefly looked at the
> > > FLIRT source code, but it was probably too brief. Is it a Quaternion
> > in
> > > DOF=7?
> > >
> > > Thanks for explanation.
> > >
> > > Martin
> > >
> > >
> > --
> > Christian F. Beckmann
> > Oxford University Centre for Functional
> > Magnetic Resonance Imaging of the Brain,
> > John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
> > Email: [log in to unmask] -
> > http://www.fmrib.ox.ac.uk/~beckmann/
> > Phone: +44(0)1865 222782 Fax: +44(0)1865 222717
> >
>
Stephen M. Smith DPhil
Associate Director, FMRIB and Analysis Research Coordinator
Oxford University Centre for Functional MRI of the Brain
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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