Dear Colin,
> Another question related to the last post. In the transform denoted by equation A1, M_s and M_q are defined as matrices that map a voxel-coordinate vector into a mm-coordinate vector and that these map the geometric center of spaces S and Q to mm-coordinate (0,0,0). Is is correct to say that the mapping of a voxel coordinate to a mm-coordinate is simply the distance of a given voxel from the geometric center given the voxel dimensions?
yes, I think so. An index/voxel-coordinate is essentially the distance from your [0,0,0] corner, in units of voxels. The mm-coordinate is the distance from the geometric center in mm.
N.B. that (slightly unfortunately) the internal FLIRT coordinates is the distance from the corner in mm, whereas for eddy it is the distance from the geometric center in mm.
Jesper
>
> Thanks,
> Colin
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