AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

History of AFNI updates  

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March 24, 2010 09:19AM
I'm trying to produce an image volume containing noise, with a given spatial smoothness. I tried this:

3dcalc -a 'filtered_func_data.nii.gz[0]' -expr 'a*0+gran(0,1)' -prefix noise.nii.gz

which gives me noise as expected, then:

3dBlurToFWHM -input noise.nii.gz -blurmaster noise.nii.gz -prefix smoothnoise.nii.gz -FWHM 5

This program fails to converge. The estimated smoothness peaks and then starts declining. The output shows regions of smoothness and others equal to the input.

What am I doing wrong?

Subject Author Posted

Blurry noise

Blurry noise March 24, 2010 09:19AM