> I have tried to insert in defaults for normalization
> NaN for bb and voxel size. I utilize SPM99. But by
> these parameters, I obtain an image completely equal
> to 0.
> As to voxel size, I can insert the right values from
> my CT reference. As to bb, I don't know what to
> insert. I have a reference CT by voxel size of
> 0.613x0.613x2 and 512x512x65 pixel. How to calculate
> the parameters of bb, please?
> Another question: do you think that spatial
> normalization can work well also for multimodalities
> images (CT-3DRA)?
The NaN thing only works in SPM2. For SPM99, you can try to
figure out a bounding box by:
P = spm_get(1,'n*.IMAGE','Select spatially normalised image')
V = spm_vol(P);
vx = sqrt(sum(V.mat(1:3,1:3).^2));
if det(V.mat(1:3,1:3))<0, vx(1) = -vx(1); end;
o = V.mat\[0 0 0 1]';
o = o(1:3)';
bb = [-vx.*(o-1) ; vx.*(V.dim(1:3)-o)];
disp(vx)
disp(bb)
Best regards,
-John
--
Dr John Ashburner.
Functional Imaging Lab., 12 Queen Square, London WC1N 3BG, UK.
tel: +44 (0)20 78337491 or +44 (0)20 78373611 x4381
fax: +44 (0)20 78131420 http://www.fil.ion.ucl.ac.uk/~john
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