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DICOM to NIfTI Converter (dcm2niix)

Library: dcm2niix | Docker Image: xnat/dcm2niix

Function

Converts DICOM medical images to NIfTI format with BIDS-compatible JSON sidecar files, preserving acquisition metadata.

Modality: DICOM image directory from any MRI acquisition.

Typical Use: First step in any neuroimaging pipeline: converting raw DICOM acquisitions to analysis-ready NIfTI.

Key Parameters

-o (output directory), -f (filename format), -z (compression: y/n/o/i), -b (BIDS sidecar: y/n/o)

Key Points

Generates BIDS-compatible JSON sidecars. Handles multi-echo, diffusion (bval/bvec), and Philips/Siemens/GE formats. Default filename format is %f_%p_%t_%s.

Inputs

Name Type Required Label Flag
input_dir Directory Yes Input DICOM directory
filename string No Output filename format (default %f_%p_%t_%s) -f
compress enum No Compression (y=pigz, o=optimal, i=internal, n=none, 3=save .nii and .gz) -z
merge enum No Merge 2D slices (0=no, 1=yes, 2=auto) -m
single_file enum No Single file mode for 4D (y/n) -s
bids enum No BIDS sidecar (y=yes, n=no, o=only) -b
anonymize enum No Anonymize BIDS sidecar (y/n) -ba
ignore_derived boolean No Ignore derived/localizer/2D images -i
verbose enum No Verbosity level (0=none, 1=some, 2=all) -v

Outputs

Name Type Glob Pattern
nifti_files File[] *.nii.gz, *.nii
json_sidecars File[] *.json
bval_files File[] *.bval
bvec_files File[] *.bvec
log File dcm2niix.log

Output Extensions

  • nifti_files: .nii, .nii.gz
  • json_sidecars: .json
  • bval_files: .bval
  • bvec_files: .bvec

Docker Tags

Available versions: latest, 1.0.20240202

Categories

  • Utilities > dcm2niix > Format Conversion

Documentation

Official Documentation