The usage says
-g <g> vertical gradient in fractional intensity threshold (-1->1); default=0; positive values give larger brain outline at bottom, smaller at top
I would have expected "bottom" and "top" to refer to the real world.
I still think that referring to a direction given by the data ordering
rather than the NIfTI header is a bug.
On Wed, Mar 25, 2009 at 03:19:07PM +0000, Steve Smith wrote:
> Hi - yes, the -g option refers to a vertical gradient on the -f option
> - if you want any other gradient you will need to reorient your image
> first.
> The usage lines says this ;-)
> Cheers.
>
>
>
> On 25 Mar 2009, at 14:24, Rolf Heckemann wrote:
>
> > I am getting different results from BET depending on the data ordering
> > in the NIfTI file. It appears that BET relies on the data ordering to
> > determine the vertical axis in the image. I would expect BET results
> > to be identical on pairs of files that only differ by the data
> > ordering.
> >
> > I've illustrated the problem on this page:
> >
> > http://www.soundray.org/betbugdemo
> >
> >
> > --
> > Rolf A Heckemann, PhD
> > Research Associate
> > Division of Neuroscience and Mental Health
> > MRC Clinical Sciences Centre
> > Imperial College London
> > Hammersmith Hospital Campus
> > Du Cane Road
> > London W12 0HS
> > United Kingdom
> > 1237990828
> >
>
>
> ---------------------------------------------------------------------------
> Stephen M. Smith, Professor of Biomedical Engineering
> Associate Director, Oxford University FMRIB Centre
>
> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
> +44 (0) 1865 222726 (fax 222717)
> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
> ---------------------------------------------------------------------------
--
Rolf A Heckemann, PhD
Research Associate
Division of Neuroscience and Mental Health
MRC Clinical Sciences Centre
Imperial College London
Hammersmith Hospital Campus
Du Cane Road
London W12 0HS
United Kingdom
1237995727
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