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Motion Correction using FLIRT (MCFLIRT)

Library: FSL | Docker Image: brainlife/fsl

Function

Intra-modal motion correction for fMRI time series using rigid-body (6-DOF) transformations optimized for fMRI data.

Modality: 4D fMRI NIfTI time series.

Typical Use: Correcting head motion in functional data; motion parameters used as nuisance regressors.

Key Parameters

-refvol (reference volume index), -cost (cost function), -plots (output motion parameter plots), -mats (save transformation matrices)

Key Points

Default reference is middle volume. Use -plots for motion parameter files (6 columns: 3 rotations + 3 translations). Motion params useful as nuisance regressors.

Inputs

Name Type Required Label Flag
input File Yes Input 4D timeseries to motion-correct -in
output string Yes Output filename -out
ref_vol int No Reference volume number (default is middle volume) -refvol
ref_file File No External reference image for motion correction -reffile
mean_vol boolean No Register to mean volume -meanvol
cost enum No Cost function for optimization -cost
dof int No Degrees of freedom (default 6) -dof
init File No Initial transformation matrix -init
interpolation enum No Final interpolation method
save_mats boolean No Save transformation matrices -mats
save_plots boolean No Save motion parameter plots -plots
save_rms boolean No Save RMS displacement parameters -rmsabs
stats boolean No Produce variance and std dev images -stats
stages int No Number of search stages (default 3) -stages
bins int No Number of histogram bins -bins
smooth double No Smoothing for cost function (FWHM in mm) -smooth
scaling double No Scaling factor -scaling
rotation int No Rotation tolerance scaling factor -rotation
edge boolean No Use contour for coarse search -edge
gdt boolean No Use gradient for coarse search -gdt

Accepted Input Extensions

  • input: .nii, .nii.gz
  • ref_file: .nii, .nii.gz
  • init: .mat

Outputs

Name Type Glob Pattern
motion_corrected File $(inputs.output).nii.gz, $(inputs.output).nii
motion_parameters File $(inputs.output).par
mean_image File $(inputs.output)_mean_reg.nii.gz, $(inputs.output)_mean_reg.nii
variance_image File $(inputs.output)_variance.nii.gz, $(inputs.output)_variance.nii
std_image File $(inputs.output)_sigma.nii.gz, $(inputs.output)_sigma.nii
transformation_matrices File[] $(inputs.output).mat/MAT_*
rms_files File[] $(inputs.output)_abs.rms, $(inputs.output)_rel.rms, $(inputs.output)_abs_mean.rms, $(inputs.output)_rel_mean.rms
log File mcflirt.log

Output Extensions

  • motion_corrected: .nii, .nii.gz
  • motion_parameters: .par
  • mean_image: .nii, .nii.gz
  • variance_image: .nii, .nii.gz
  • std_image: .nii, .nii.gz
  • transformation_matrices: .mat
  • rms_files: .rms

Enum Options

cost: mutualinfo, corratio, normcorr, normmi, leastsquares

Docker Tags

Available versions: latest, 6.0.4-patched2, 6.0.4-patched, 6.0.4, 6.0.4-xenial, 5.0.11, 6.0.0, 6.0.1, 5.0.9

Categories

  • Functional MRI > FSL > Motion Correction

Documentation

Official Documentation