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AFNI 3D Merge and Smooth (3dmerge)

Library: AFNI | Docker Image: brainlife/afni

Function

Combines spatial filtering and dataset merging operations, commonly used for Gaussian smoothing.

Modality: 3D or 4D NIfTI/AFNI volume.

Typical Use: Gaussian smoothing of functional data.

Key Parameters

-1blur_fwhm (FWHM in mm), -doall (process all sub-bricks), -prefix (output)

Key Points

Simple Gaussian smoothing with -1blur_fwhm. -doall applies to all volumes in 4D.

Inputs

Name Type Required Label Flag
input File Yes Input dataset
prefix string Yes Output dataset prefix -prefix
blur_fwhm double No Gaussian blur with FWHM (mm) -1blur_fwhm
blur_sigma double No Gaussian blur with sigma (mm) -1blur_sigma
blur_rms double No Gaussian blur with RMS deviation (mm) -1blur_rms
thtoin boolean No Copy threshold data over intensity data -1thtoin
noneg boolean No Zero out negative intensity voxels -1noneg
abs boolean No Take absolute values of intensities -1abs
clip double No Clip intensities in range (-val,val) to zero -1clip
thresh double No Use threshold data to censor intensities -1thresh
mult double No Multiply intensities by given factor -1mult
zscore boolean No Convert statistic to equivalent z-score -1zscore
clust string No Form clusters with rmm vmul (e.g., "5 100") -1clust
clust_mean string No Replace cluster voxels with average intensity -1clust_mean
clust_max string No Replace cluster voxels with maximum intensity -1clust_max
filter_mean double No Set each voxel to average intensity within radius (mm) -1filter_mean
filter_max double No Maximum intensity within radius (mm) -1filter_max
filter_blur double No Gaussian blur filter with FWHM (mm) -1filter_blur
erode double No Set voxel to zero unless pv% of nearby voxels are nonzero -1erode
dilate boolean No Restore voxels removed by erosion if neighbors exist -1dilate
dindex int No Use sub-brick j as data source -1dindex
tindex int No Use sub-brick k as threshold source -1tindex
doall boolean No Apply options to all sub-bricks uniformly -doall
datum enum No Output data storage type -datum
nozero boolean No Do not write output if all zero -nozero
quiet boolean No Reduce message output -quiet

Accepted Input Extensions

  • input: .nii, .nii.gz, +orig.HEAD, +orig.BRIK, +tlrc.HEAD, +tlrc.BRIK

Outputs

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

Output Extensions

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

Docker Tags

Available versions: latest, 16.3.0

Categories

  • Functional MRI > AFNI > Smoothing

Documentation

Official Documentation