FSL uses the analyze file format and bet should work with:

8bit unsigned ints
8bit signed ints
16bit unsigned ints
16bit signed ints
32bit unsigned ints
32bit signed ints
32bit reals

You can use avwhd to check the .hdr file


Qingyan Guan wrote:
> Hi,
> I am new user of fsl program.
> what is the data format for BET. I input a AVW image file named E118S234.MR
> into BET, then I got a error that can not open file E118S234.hdr.
> If I change E118S234.MR file to E118S234.hdr, Then I got that " bet has not
> been compliled for the data type of E118S234". What is the problem, how can
> I solve it?
> QingYan Guan
> [log in to unmask]
> (425)391-8251
> _________________________________________________________________
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 Christian F. Beckmann
 Address: Oxford University Centre for Functional
          Magnetic Resonance Imaging of the Brain,
          John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
 Email:   [log in to unmask] Phone: +44(0)1865 222704 Fax: 222717