Hi - that's right, fslcc returns abs(cc)
You can see the source in
$FSLDIR/src/avwutils/fslcc.cc
We have on our todo list for future releases to have an option to keep
the sign but you can easily amend the code and recompile.
Cheers.
On 12 Mar 2009, at 19:31, Ariana Anderson wrote:
> Hello,
>
> I've tried fslcc, but all the values returned were all suspiciously
> positive. Does fslcc return the correlation-squared and not the
> actual
> correlation? It seems odd that for the 85 images all 85-choose-2
> correlations were positive. I did set the threshold for fslcc to
> -1, so it
> returned ALL possible correlation pairs. Is there source code
> available so
> I can see how fslcc is calculated?
>
> I'll try out the script next or move on to Matlab.
>
> Thank you again,
>
> Ariana
>
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