> I need to extact some voxel values from some normalized images. I've write
> a short matlab script to do that, but I need to know in which order voxels
> are stored to know which index of image (readed as a raw with fread
> command) corresponds to which position of image. In other words, if A is
> the raw that contains the value of all the voxels, should I trasform A to a
> 3-dim matrix by using reshape(A,[X-dim Ydim Z-dim]), reshape(A,[Zdim Ydim
> Xdim] or reshape(A,[Zdim Xdim Ydim])?
Transform it with reshape(A,[X-dim Ydim Z-dim]). Raw data can be in any
orientation. In these cases, the .mat file gives you a mapping from voxels
(where the first is [1,1,1]), to millimetres in some space. See the
following for more info:
http://www.fil.ion.ucl.ac.uk/spm/spm2.html#Compat
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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