Dear FSL experts,
I have a couple of questions to ask about
1- I think this one is a bug: if you try to do integer pixel shifts
using flirt (like this)
> flirt -in spgr.hdr -ref spgr.hdr -out upspgr.hdr -init up1.mat -
> applyxfm
where up1.mat contains an INTEGER z-direction shift only, flirt
doesn't do anything at all to the image. With non-integer shifts it
works fine though.
2. I think that this other one is lack of knowing the correct usage:
Lets say that I run mcflrt on a time series of images (structs.img)
and produce rstructs.mat/MAT000* series of matrices. I want to apply
those MAT transformations to a set of corresponding field maps.
applyxfm4D fmaps.img r_fmaps.img fmaps.img rstructs.mat -fourdigit
The resulting rotated images have crazy rotations/translations
(except fot the first one) even though the original realigned
structurals have been realigned properly.
Could someone tell me what's wrong? What are the units in the .par
files? is it mm and degrees?
Thank you very much,
-Luis
Begin forwarded message:
> From: "Robert Welsh" <[log in to unmask]>
> Date: July 13, 2005 2:47:37 PM EDT
> To: <[log in to unmask]>
> Subject: flirt command
>
>
> bug is when the transformation matrix appears to have unit voxel
> shift.
>
> flirt -in spgr.hdr -ref spgr.hdr -out upspgr.hdr -init up1.mat -
> applyxfm
>
>
> -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> Robert C. Welsh, PhD
> Research Investigator
> Department of Radiology
> University of Michigan
> (734) - 764 - 2412 (fax)
> [log in to unmask]
>
>
>
>
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