3dTsmooth


Usage: 3dTsmooth [options] dataset
Smooths each voxel time series in a 3D+time dataset and produces
as output a new 3D+time dataset (e.g., lowpass filter in time).

*** Also see program 3dBandpass ***

General Options:
  -prefix ppp  = Sets the prefix of the output dataset to be 'ppp'.
                   [default = 'smooth']
  -datum type  = Coerce output dataset to be stored as the given type.
                   [default = input data type]

Three Point Filtering Options [07 July 1999]
--------------------------------------------
The following options define the smoothing filter to be used.
All these filters  use 3 input points to compute one output point:
  Let a = input value before the current point
      b = input value at the current point
      c = input value after the current point
           [at the left end, a=b; at the right end, c=b]

  -lin = 3 point linear filter: 0.15*a + 0.70*b + 0.15*c
           [This is the default smoother]
  -med = 3 point median filter: median(a,b,c)
  -osf = 3 point order statistics filter:
           0.15*min(a,b,c) + 0.70*median(a,b,c) + 0.15*max(a,b,c)

  -3lin m = 3 point linear filter: 0.5*(1-m)*a + m*b + 0.5*(1-m)*c
              Here, 'm' is a number strictly between 0 and 1.

General Linear Filtering Options [03 Mar 2001]
----------------------------------------------
  -hamming N  = Use N point Hamming or Blackman windows.
  -blackman N     (N must be odd and bigger than 1.)
  -custom coeff_filename.1D (odd # of coefficients must be in a
                             single column in ASCII file)
   (-custom added Jan 2003)
    WARNING: If you use long filters, you do NOT want to include the
             large early images in the program.  Do something like
                3dTsmooth -hamming 13 'fred+orig[4..$]'
             to eliminate the first 4 images (say).
 The following options determine how the general filters treat
 time points before the beginning and after the end:
  -EXTEND = BEFORE: use the first value; AFTER: use the last value
  -ZERO   = BEFORE and AFTER: use zero
  -TREND  = compute a linear trend, and extrapolate BEFORE and AFTER
 The default is -EXTEND.  These options do NOT affect the operation
 of the 3 point filters described above, which always use -EXTEND.

Adaptive Mean Filtering option [03 Oct 2014]
--------------------------------------------
  -adaptive N = use adaptive mean filtering of width N
                (where N must be odd and bigger than 3).
              * This filter is similar to the 'AdptMean9'
                1D filter in the AFNI GUI, except that the
                end points are treated differently.

INPUT DATASET NAMES
-------------------
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 17 2024 {AFNI_24.3.10:linux_ubuntu_24_64}