++ 3dFWHM: AFNI version=AFNI_2011_12_21_1014 (Dec 16 2015) [64-bit] ++ Authored by: B. Douglas Ward *+ WARNING: This program is obsolete! Use 3dFWHMx instead!! This program estimates the Filter Width Half Maximum (FWHM).
3dFWHM itself will no longer be upgraded. Any future improvements will be made to 3dFWHMx. **** PLEASE SWITCH TO THAT PROGRAM ****
Usage: 3dFWHM
-dset file file = name of input AFNI 3d dataset
[-mask mname] mname = filename of 3d mask dataset
[-quiet] suppress screen output
[-out file] file = name of output file
voxel is in the mask, then its neighbors are used for differencing, even if they are not themselves in the mask. This was an error; now, neighbors must also be in the mask to be used in the differencing. Use ‘-compat’ to use the older method [for comparison].
** This change made 09 Nov 2006.
3dFWHM itself will no longer be upgraded. Any future improvements will be made to 3dFWHMx. **** PLEASE SWITCH TO THAT PROGRAM ****
INPUT FILE RECOMMENDATIONS: For FMRI statistical purposes, you DO NOT want the FWHM to reflect the spatial structure of the underlying anatomy. Rather, you want the FWHM to reflect the spatial structure of the noise. This means that the input dataset should not have anatomical structure. One good form of input is the output of ‘3dDeconvolve -errts’, which is the residuals left over after the GLM fitted signal model is subtracted out from each voxel’s time series. If you don’t want to go to that trouble, use the output of 3dDetrend for the same purpose. But just giving a raw EPI dataset to this program will produce un-useful values.
This program accepts datasets that are modified on input according to the following schemes:
‘r1+orig[3..5]’ {sub-brick selector} ‘r1+orig<100..200>’ {sub-range selector} ‘r1+orig[3..5]<100..200>’ {both selectors} ‘3dcalc( -a r1+orig -b r2+orig -expr 0.5*(a+b) )’ {calculation}
For the gruesome details, see the output of ‘afni -help’.
++ Compile date = Dec 16 2015