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AFNI Skull Strip and Nonlinear Warp (@SSwarper)

Library: AFNI | Docker Image: brainlife/afni

Function

Combined skull stripping and non-linear warping to template in a single optimized pipeline.

Modality: T1-weighted 3D NIfTI volume plus reference template.

Typical Use: Modern anatomical preprocessing for afni_proc.py pipelines.

Key Parameters

-input (T1 image), -base (template), -subid (subject ID), -odir (output dir)

Key Points

Preferred over separate skull-strip + registration. Output compatible with afni_proc.py.

Inputs

Name Type Required Label Flag
input File Yes Input anatomical dataset (non-skull-stripped, ~1mm resolution) -input
base File Yes Base template dataset with similar contrast -base
subid string Yes Subject ID code for output datasets -subid
odir string No Output directory (default is input directory) -odir
minp int No Minimum patch size for 3dQwarp (default 11) -minp
warpscale double No Control warp flexibility (0.1-1.0, default 1.0) -warpscale
skipwarp boolean No Stop after skull-stripping, skip warping to template -skipwarp
deoblique boolean No Apply obliquity correction using 3dWarp -deoblique
deoblique_refitly boolean No Remove obliquity information via 3drefit -deoblique_refitly
unifize_off boolean No Skip intensity uniformization step -unifize_off
aniso_off boolean No Skip anisotropic smoothing preprocessing -aniso_off
ceil_off boolean No Skip ceiling value capping at 98th percentile -ceil_off
init_skullstr_off boolean No Skip initial skull-stripping pass -init_skullstr_off
cost_nl_init string No Cost function for initial nonlinear alignment (default lpa) -cost_nl_init
cost_nl_final string No Cost function for final nonlinear alignment (default pcl) -cost_nl_final
giant_move boolean No Apply expanded parameter alignment for extreme angles -giant_move
mask_ss File No Provide mask instead of performing skull-stripping -mask_ss
SSopt string No Additional options passed to 3dSkullStrip -SSopt
extra_qc_off boolean No Omit extra QC JPEG images -extra_qc_off
nolite boolean No Disable lite option in 3dQwarp -nolite
verb boolean No Enable verbose 3dQwarp output -verb
noclean boolean No Preserve temporary files after completion -noclean

Accepted Input Extensions

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

Outputs

Name Type Glob Pattern
skull_stripped File anatSS.$(inputs.subid).nii, anatSS.$(inputs.subid).nii.gz
warped File anatQQ.$(inputs.subid)+tlrc.HEAD, anatQQ.$(inputs.subid)+tlrc.BRIK, anatQQ.$(inputs.subid)+tlrc.BRIK.gz, anatQQ.$(inputs.subid).nii, anatQQ.$(inputs.subid).nii.gz
warp File anatQQ.$(inputs.subid)_WARP+tlrc.HEAD, anatQQ.$(inputs.subid)_WARP+tlrc.BRIK, anatQQ.$(inputs.subid)_WARP+tlrc.BRIK.gz, anatQQ.$(inputs.subid)_WARP.nii, anatQQ.$(inputs.subid)_WARP.nii.gz
affine File anatQQ.$(inputs.subid).aff12.1D
log File $(inputs.subid)_SSwarper.log

Output Extensions

  • skull_stripped: .nii, .nii.gz
  • warped: +tlrc.HEAD, +tlrc.BRIK, .nii, .nii.gz
  • warp: +tlrc.HEAD, +tlrc.BRIK, .nii, .nii.gz
  • affine: .aff12.1D

Docker Tags

Available versions: latest, 16.3.0

Categories

  • Structural MRI > AFNI > Brain Extraction

Documentation

Official Documentation