Hi,
It appears that FSL behaves unexpected on some servers, with 0/1 float data being potentially read as NaN.
On a Centos server, looking at minimum and maximum values of such a "float 32" binary image (fslstats -R my_image.nii.gz) gives -nan -nan. When I copy the same file on my Ubuntu system with the same version of fsl (5.0.9) as the Centos server, I obtain the correct range, 0.000000 1.000000.
Please note that it was particularly hard to debug the whole workflow to pinpoint this issue in FSL behavior on different OS systems. I assume other users had this issue but could not find the origin of their errors. I could find an unelegant solution which consists in converting the image to int (fslmaths -odt int) [which provided the range -2147483648.000000 1.000000], and then binarizing it, to obtain the correct image (with range 0.000000 1.000000).
Would someone have more insight and what is actually happening? It seems related to data type reading from different OS but I am not clear of the exact mechanism.
Many thanks,
Michael
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