hi - the normal thing to do is to have most of the image (including the
background - this is important) set to say 1 and just a few areas that you
want to ignore set to 0. If this doesn't work, feel free to put an example
pair on a website and we'll take a look.
thanks, Steve.
On Fri, 11 Jul 2003, Mike Bristow wrote:
> Hi,
>
> I am trying to use the "weighting volumes" functionality of FLIRT but the
> results are ugly. Registering two volumes without the weighting volume
> inputs gives me OK results but I would like to refine the registration by
> ignoring noise and have tried to use masks as weighting volume inputs. I've
> tried masking one and both inputs. I tried masking the noise with 0 values
> and the areas of interest with values of 1 and again with 10 but the results
> are way off (wedges of noise or large rotations and translations). Could I
> be doing something wrong?
>
> Thanks,
> Mike Bristow
>
Stephen M. Smith MA DPhil CEng MIEE
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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