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AFNI 3D Bandpass Filter (3dBandpass)

Library: AFNI | Docker Image: brainlife/afni

Function

Applies temporal bandpass filtering to fMRI time series with optional simultaneous nuisance regression.

Modality: 4D fMRI NIfTI/AFNI time series.

Typical Use: Resting-state frequency filtering (typically 0.01-0.1 Hz).

Key Parameters

(frequency range in Hz), -prefix (output), -ort (nuisance regressors file)

Key Points

Typical resting-state range: 0.01-0.1 Hz. Can simultaneously regress nuisance signals with -ort.

Inputs

Name Type Required Label Flag
input File Yes Input 3D+time dataset
prefix string Yes Output dataset prefix -prefix
fbot double Yes Lowest frequency in passband (Hz), can be 0 for lowpass
ftop double Yes Highest frequency in passband (Hz)
band string No Alternative passband specification (fbot ftop) -band
despike boolean No Remove spikes from time series before processing -despike
nodetrend boolean No Skip quadratic detrending before FFT bandpassing -nodetrend
notrans boolean No Skip initial transient checking -notrans
ort File No Orthogonalize input to columns in 1D file -ort
dsort File No Orthogonalize each voxel to matching voxel in dataset -dsort
dt double No Set time step in seconds (default from header) -dt
nfft int No Specify FFT length -nfft
mask File No Apply mask dataset -mask
automask boolean No Generate mask from input dataset -automask
blur double No Apply spatial filtering with specified FWHM (mm) -blur
localPV double No Replace vectors with local principal vector (radius in mm) -localPV
norm boolean No Normalize output time series to L2 norm = 1 -norm
quiet boolean No Suppress informational messages -quiet

Accepted Input Extensions

  • input: .nii, .nii.gz, +orig.HEAD, +orig.BRIK, +tlrc.HEAD, +tlrc.BRIK
  • ort: .1D, .txt
  • dsort: .nii, .nii.gz, +orig.HEAD, +orig.BRIK, +tlrc.HEAD, +tlrc.BRIK
  • mask: .nii, .nii.gz, +orig.HEAD, +orig.BRIK, +tlrc.HEAD, +tlrc.BRIK

Outputs

Name Type Glob Pattern
filtered File $(inputs.prefix)+orig.HEAD, $(inputs.prefix)+tlrc.HEAD
log File $(inputs.prefix).log

Output Extensions

  • filtered: +orig.HEAD, +orig.BRIK, +tlrc.HEAD, +tlrc.BRIK

Docker Tags

Available versions: latest, 16.3.0

Categories

  • Functional MRI > AFNI > Denoising

Documentation

Official Documentation