An external .mat file is used to save the relative orientations of the
volumes in the 4D file. In SPM, if there is a .mat file, then the
orientations should be read from it.
Best regards,
-John
On Tue, 2009-06-02 at 13:22 -0700, Neil Chatterjee wrote:
> I wanted to add one caveat because there is very sneaky problem with
> realignment and 4D files. In 4D nifti files, all of the volumes share
> the same header. So if you run something like realignment w/o
> reslicing, which works by adjusting image headers relative to eachother,
> you'll end up doing nothing. You can test it out by taking a 4D file,
> rotating only one volume, and then looking at a different volume.
> Perhaps things have changed in SPM8, but last I tried this both volumes
> would be rotated. It's for this reason I prefer to keep my files in 3D,
> even if it clutters up my filesystem. Just my $.02 .....
>
> -Neil
>
> John Ashburner wrote:
> > In the file selector, try changing the field that usually says "1" to
> > something like 1:1000
> >
> > Best regards,
> > -John
> >
> > On Tue, 2009-06-02 at 11:50 -0700, Michael T Rubens wrote:
> >
> >> convert .imgs to 4D nifti. (see spm_config_3Dto4D)
> >>
> >> Cheers,
> >> Michael
> >>
> >> On Tue, Jun 2, 2009 at 11:02 AM, Eric Mansfield
> >> <[log in to unmask]> wrote:
> >> Good Day,
> >> I was wondering, does SPM8 support 4D .img files? I've tried
> >> loading 4D .img
> >> files into the realign function and it only loads the first
> >> image. Is it possible for
> >> me load my entire time series without breaking it into
> >> individual 3D .img files?
> >>
> >> Thank you,
> >>
> >> Eric Mansfield
> >> Duke Brain Imaging
> >> and Analysis Center
> >>
> >>
> >>
> >> --
> >> Research Associate
> >> Gazzaley Lab
> >> Department of Neurology
> >> University of California, San Francisco
> >>
>
--
John Ashburner <[log in to unmask]>
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