scientific-skills/bids/SKILL.md
The Brain Imaging Data Structure (BIDS) is a community standard for organizing and describing neuroscience and biomedical research datasets. It defines a consistent file naming convention, directory hierarchy, and metadata schema so that datasets are immediately understandable by humans and software tools alike. BIDS is governed by the BIDS Specification (currently v1.11.x) and is maintained by the community via the BIDS-Standard GitHub organization.
While BIDS originated for MRI, it has grown well beyond neuroimaging. The specification now covers 11 modalities spanning imaging, electrophysiology, and behavioral data:
Active BEPs are extending BIDS further — notably BEP032 (microelectrode electrophysiology) will add support for extracellular recordings including Neuropixels probes, bringing BIDS to a prevalent methodology in animal neuroscience research (see also the neuropixels-analysis skill).
Adoption is required or strongly encouraged by major data repositories (OpenNeuro, DANDI), leading journals (NeuroImage, Human Brain Mapping, Scientific Data), and funding agencies (NIH, ERC).
The Python ecosystem for BIDS centers on PyBIDS (pybids) for querying and indexing BIDS datasets, and the bids-validator (Deno-based, available as PyPI package bids-validator-deno or via Deno directly) for compliance checking. Conversion from DICOM is typically done with HeuDiConv, dcm2bids, or BIDScoin.
Apply this skill when:
dataset_description.json for a new dataset.bidsignore to exclude files from validation# Core BIDS querying library
uv pip install pybids
# BIDS validator (Deno-based, installed via PyPI wrapper)
uv pip install bids-validator-deno
# Alternative: install directly via Deno
# deno install -g -A npm:bids-validator
# DICOM-to-BIDS converters (install as needed)
uv pip install heudiconv # HeuDiConv - heuristic-based DICOM conversion
uv pip install dcm2bids # dcm2bids - config-file-based conversion
# BIDScoin: uv pip install bidscoin
# Useful companions
uv pip install nibabel # NIfTI/other neuroimaging file I/O
uv pip install pydicom # DICOM file reading (used by converters)
A minimal BIDS dataset follows this layout:
my_dataset/
dataset_description.json # Required: name, BIDSVersion, etc.
participants.tsv # Recommended: subject-level phenotypic data
participants.json # Recommended: column descriptions
README # Recommended: dataset documentation
CHANGES # Recommended: version history
.bidsignore # Optional: patterns to exclude from validation
sub-01/
anat/
sub-01_T1w.nii.gz
sub-01_T1w.json # Sidecar metadata
func/
sub-01_task-rest_bold.nii.gz
sub-01_task-rest_bold.json
sub-01_task-rest_events.tsv # Event timing for task fMRI
sub-01_task-rest_events.json
dwi/
sub-01_dwi.nii.gz
sub-01_dwi.json
sub-01_dwi.bvec
sub-01_dwi.bval
fmap/
sub-01_phasediff.nii.gz
sub-01_phasediff.json
sub-01_magnitude1.nii.gz
perf/
sub-01_asl.nii.gz
sub-01_asl.json
sub-01/
ses-pre/
anat/
sub-01_ses-pre_T1w.nii.gz
func/
sub-01_ses-pre_task-nback_bold.nii.gz
ses-post/
...
Key points:
.json sidecarsub-<label>[_ses-<label>][_task-<label>][_acq-<label>][_run-<index>]_<suffix>.<extension>dataset_description.json is strictly required at the root levelimport json
dataset_description = {
"Name": "My Neuroimaging Study",
"BIDSVersion": "1.10.0",
"DatasetType": "raw",
"License": "CC0",
"Authors": ["First Author", "Second Author"],
"Acknowledgements": "Funded by NIH R01-MH123456",
"HowToAcknowledge": "Please cite: Author et al. (2025) Journal Name.",
"Funding": ["NIH R01-MH123456", "NSF BCS-7654321"],
"ReferencesAndLinks": ["https://doi.org/10.xxxx/xxxxx"],
"DatasetDOI": "10.18112/openneuro.ds000001.v1.0.0",
"GeneratedBy": [
{
"Name": "HeuDiConv",
"Version": "1.3.1",
"CodeURL": "https://github.com/nipy/heudiconv"
}
]
}
with open("dataset_description.json", "w") as f:
json.dump(dataset_description, f, indent=4)
For derivatives, set "DatasetType": "derivative" and add "GeneratedBy" listing the pipeline:
deriv_description = {
"Name": "fMRIPrep - fMRI PREProcessing",
"BIDSVersion": "1.10.0",
"DatasetType": "derivative",
"GeneratedBy": [
{
"Name": "fMRIPrep",
"Version": "24.1.0",
"CodeURL": "https://github.com/nipreps/fmriprep"
}
]
}
from bids import BIDSLayout
# Index a BIDS dataset (validates structure on load)
layout = BIDSLayout("/path/to/bids_dataset")
# Basic queries
subjects = layout.get_subjects() # ['01', '02', '03', ...]
sessions = layout.get_sessions() # ['pre', 'post'] or []
tasks = layout.get_tasks() # ['rest', 'nback']
runs = layout.get_runs() # [1, 2] or []
# Find specific files
bold_files = layout.get(
suffix="bold",
extension=".nii.gz",
return_type="filename"
)
# Filter by subject, task, session
nback_sub01 = layout.get(
subject="01",
task="nback",
suffix="bold",
extension=".nii.gz",
return_type="filename"
)
# Get metadata from JSON sidecars (automatic inheritance)
metadata = layout.get_metadata("/path/to/sub-01/func/sub-01_task-rest_bold.nii.gz")
tr = metadata["RepetitionTime"]
# Get all entities for a file
entities = layout.get_entities()
# Build a path from entities using BIDSLayout
bids_file = layout.get(subject="01", suffix="T1w", extension=".nii.gz")[0]
print(bids_file.path)
print(bids_file.get_entities())
Key points:
BIDSLayout indexes the entire dataset on initialization; for large datasets use database_path to cache the indexreturn_type="filename" for paths, return_type="object" (default) for BIDSFile objectsThe bids-validator-deno PyPI package bundles the Deno-based validator as a standalone CLI:
# Install
uv pip install bids-validator-deno
# Validate a dataset
bids-validator /path/to/bids_dataset
# Ignore specific warnings/errors
bids-validator /path/to/bids_dataset --ignoreNiftiHeaders --ignoreSubjectConsistency
If Deno is already available, you can install or run the validator without PyPI:
# Install globally via Deno
deno install -g -A npm:bids-validator
# Or run without installing
deno run -A npm:bids-validator /path/to/bids_dataset
The older Node.js-based validator (npm install -g bids-validator) is deprecated in favor of the Deno-based version. The Deno version is the reference implementation for BIDS Specification v1.9+.
Create .bidsignore at the dataset root to exclude files from validation (gitignore syntax):
# Exclude sourcedata and extra files
sourcedata/
extra_data/
*.log
*_sbref.nii.gz
**/.DS_Store
The authoritative, machine-readable source of truth for entities, their ordering, allowed suffixes, and all filename rules is the BIDS Schema — a structured YAML/JSON representation of the specification. A JSON export is shipped with this skill at references/bids_schema.json. The schema is defined in the bids-specification src/schema/ directory and published at https://bids-specification.readthedocs.io/en/stable/schema.json. BEP-specific schema previews are available at https://github.com/bids-standard/bids-schema/tree/main/BEPs.
Run scripts/update_schema.py to refresh the schema and BEPs list from upstream (no dependencies beyond stdlib).
The tables below are a convenient summary; when in doubt, consult the schema.
BIDS filenames are built from ordered key-value entity pairs:
| Entity | Key | Example | Required for |
|---|---|---|---|
| Subject | sub- | sub-01 | All files |
| Session | ses- | ses-pre | Multi-session studies |
| Task | task- | task-rest | func (bold, cbv, phase), eeg, meg |
| Acquisition | acq- | acq-highres | Distinguishing acquisition parameters |
| Contrast enhancing agent | ce- | ce-gadolinium | Contrast-enhanced images |
| Reconstruction | rec- | rec-magnitude | Reconstruction variants |
| Direction | dir- | dir-AP | Fieldmaps, DWI, phase-encoding |
| Run | run- | run-01 | Multiple identical acquisitions |
| Echo | echo- | echo-1 | Multi-echo sequences |
| Part | part- | part-mag | Magnitude/phase splits |
| Space | space- | space-MNI152NLin2009cAsym | Derivatives in template space |
| Description | desc- | desc-preproc | Derivatives only |
Entity ordering in filenames is fixed by the spec (defined in rules.entities in bids_schema.json). See references/bids_specification.md for the complete numbered ordering table. A common subset:
sub-<label>[_ses-<label>][_task-<label>][_acq-<label>][_ce-<label>][_rec-<label>][_dir-<label>][_run-<index>][_echo-<index>][_part-<label>][_space-<label>][_desc-<label>]_<suffix>.<extension>
Common suffixes by datatype:
| Datatype | Suffixes |
|---|---|
| anat | T1w, T2w, FLAIR, T2star, T1map, T2map, defacemask |
| func | bold, cbv, sbref, events, physio, stim |
| dwi | dwi, sbref |
| fmap | phasediff, phase1, phase2, magnitude1, magnitude2, fieldmap, epi |
| perf | asl, m0scan, aslcontext |
| eeg | eeg, channels, electrodes, events |
| meg | meg, channels, coordsystem, events |
| ieeg | ieeg, channels, electrodes, coordsystem, events |
| pet | pet, blood |
HeuDiConv is the most flexible DICOM-to-BIDS converter. It supports three usage modes — from fully automatic to fully custom — and handles duplicates, provenance tracking, and sourcedata archiving out of the box.
Mode 1: ReproIn (turnkey, recommended for new studies)
If scanner protocol names follow the ReproIn naming convention, conversion is fully automatic — no heuristic file to write:
# Turnkey conversion: HeuDiConv maps ReproIn protocol names to BIDS automatically
heudiconv --files dicom/001 -o /path/to/bids -f reproin --bids --minmeta
ReproIn protocol names encode BIDS entities directly:
anat-T1w → sub-XX/anat/sub-XX_T1w.nii.gzfunc-bold_task-rest → sub-XX/func/sub-XX_task-rest_bold.nii.gzdwi_dir-AP → sub-XX/dwi/sub-XX_dir-AP_dwi.nii.gzfmap_dir-PA → sub-XX/fmap/sub-XX_dir-PA_epi.nii.gzSession can be set once on the localizer (e.g., anat-scout_ses-pre) and ReproIn propagates it to all sequences in that Program. Subject ID is extracted from DICOM metadata. Duplicate runs are numbered automatically.
Mode 2: Custom heuristic mapping into ReproIn (for existing data)
If you already have data with non-ReproIn protocol names, you can write a thin heuristic that maps your names into ReproIn conventions, gaining all ReproIn benefits (automatic entity handling, duplicate management, etc.). See https://github.com/repronim/reproin/issues/18 for a HOWTO.
Mode 3: Custom heuristic (full flexibility)
For complex mappings, write a Python heuristic file:
# Step 1: Reconnaissance — discover DICOM series
heudiconv --files dicom/219/itbs/*/*.dcm -o Nifti/ -f convertall -s 219 -c none
# This creates .heudiconv/219/info/dicominfo.tsv — inspect it to understand
# what was acquired and map series to BIDS names.
# Step 2: Write a heuristic file (see references/conversion_tools.md)
# Step 3: Convert
heudiconv --files dicom/219/itbs/*/*.dcm -s 219 -ss itbs \
-f Nifti/code/heuristic.py -c dcm2niix --bids --minmeta -o Nifti/
See references/conversion_tools.md for complete heuristic file examples.
Key points:
dcm2niix for the actual DICOM-to-NIfTI conversion--minmeta: always use this flag to prevent excess DICOM metadata from overflowing JSON sidecars (can crash fMRIPrep/MRIQC){item:03d} in templates for auto-numbering when the same protocol is run multiple times; without it, later runs overwrite earlier ones.heudiconv/ directory: created alongside output, stores provenance (heuristic used, dicominfo.tsv, conversion records). Keep it with your data for reproducibilitysourcedata/: HeuDiConv archives original DICOMs as .tgz files under sourcedata/ for reproducibilityis_motion_corrected filter: use in heuristics to exclude scanner-generated MOCO series (e.g., if not s.is_motion_corrected)--files (explicit paths) and -d (template with {subject}, {session} placeholders) are supported for specifying DICOM input# Step 1: Generate helper output to inspect series
dcm2bids_helper -d /path/to/dicom
# Step 2: Create config file (dcm2bids_config.json)
# Step 3: Convert
dcm2bids -d /path/to/dicom -p 01 -c dcm2bids_config.json -o /path/to/bids_output
See references/conversion_tools.md for detailed configuration examples.
Every BIDS data file should have a JSON sidecar with acquisition parameters. Metadata fields follow the inheritance principle: a sidecar at a higher directory level applies to all matching files below.
Inheritance example:
my_dataset/
task-rest_bold.json # Applies to ALL rest BOLD files
sub-01/
func/
sub-01_task-rest_bold.json # Overrides/extends for sub-01 only
Critical metadata fields by modality:
For func (BOLD):
{
"RepetitionTime": 2.0,
"TaskName": "rest",
"PhaseEncodingDirection": "j-",
"TotalReadoutTime": 0.05,
"SliceTiming": [0, 0.5, 1.0, 1.5],
"EffectiveEchoSpacing": 0.00058,
"EchoTime": 0.03
}
For anat:
{
"MagneticFieldStrength": 3,
"Manufacturer": "Siemens",
"ManufacturersModelName": "Prisma",
"RepetitionTime": 2.3,
"EchoTime": 0.00293,
"FlipAngle": 8
}
For DWI:
{
"PhaseEncodingDirection": "j-",
"TotalReadoutTime": 0.05,
"EchoTime": 0.089,
"RepetitionTime": 3.4,
"MultipartID": "dwi_1"
}
Key points:
dcm2niix auto-generates most sidecar fields from DICOM headersRepetitionTime and TaskName are required for BOLDSliceTiming is essential for slice-timing correction in fMRI preprocessingPhaseEncodingDirection and TotalReadoutTime (or EffectiveEchoSpacing) are needed for distortion correctionreferences/metadata_fields.md for comprehensive field referenceTask-based fMRI requires _events.tsv files:
onset duration trial_type response_time
0.0 0.5 face 0.435
2.5 0.5 house 0.367
5.0 0.5 face 0.512
7.5 0.5 scrambled 0.298
Required columns:
onset - onset time in seconds relative to the start of the acquisitionduration - duration in seconds (use n/a for instantaneous events)Recommended columns:
trial_type - categorical label for conditionresponse_time - RT in seconds.json sidecar)participant_id age sex group handedness
sub-01 25 M control right
sub-02 30 F patient left
sub-03 28 M control right
The participants.json sidecar describes columns:
{
"age": {
"Description": "Age of the participant at time of scanning",
"Units": "years"
},
"sex": {
"Description": "Biological sex",
"Levels": {
"M": "male",
"F": "female"
}
},
"group": {
"Description": "Experimental group",
"Levels": {
"control": "Healthy control",
"patient": "Patient group"
}
},
"handedness": {
"Description": "Dominant hand",
"Levels": {
"right": "Right-handed",
"left": "Left-handed",
"ambidextrous": "Ambidextrous"
}
}
}
Processed outputs go under a derivatives/ directory:
my_dataset/
derivatives/
fmriprep-24.1.0/
dataset_description.json # DatasetType: "derivative"
sub-01/
anat/
sub-01_space-MNI152NLin2009cAsym_desc-preproc_T1w.nii.gz
sub-01_space-MNI152NLin2009cAsym_desc-brain_mask.nii.gz
func/
sub-01_task-rest_space-MNI152NLin2009cAsym_desc-preproc_bold.nii.gz
sub-01_task-rest_desc-confounds_timeseries.tsv
mriqc-24.0.0/
dataset_description.json
sub-01/
anat/
sub-01_T1w.html
func/
sub-01_task-rest_bold.html
group_T1w.tsv
group_bold.tsv
Derivative conventions:
space-<label> - template/reference space (e.g., MNI152NLin2009cAsym, T1w)desc-<label> - description of processing (e.g., preproc, brain, smoothed)res-<label> - resolution (e.g., 2 for 2mm isotropic)derivatives/dataset_description.json with GeneratedByfrom bids import BIDSLayout
from bids.layout import BIDSLayoutIndexer
# Cache the layout index for faster repeated access
layout = BIDSLayout("/path/to/dataset", database_path="/path/to/cache.db")
# Include derivatives
layout = BIDSLayout(
"/path/to/dataset",
derivatives=["/path/to/dataset/derivatives/fmriprep-24.1.0"]
)
# Get derivative files
preproc = layout.get(
subject="01",
task="rest",
desc="preproc",
suffix="bold",
space="MNI152NLin2009cAsym",
extension=".nii.gz",
return_type="filename"
)
# Get confound regressors
confounds = layout.get(
subject="01",
task="rest",
desc="confounds",
suffix="timeseries",
extension=".tsv",
return_type="filename"
)
# Build BIDS path from entities
from bids import BIDSLayout
layout = BIDSLayout("/path/to/dataset")
path = layout.build_path(
{
"subject": "01",
"session": "pre",
"task": "rest",
"suffix": "bold",
"extension": ".nii.gz",
"datatype": "func"
},
validate=True
)
# Get all files for a subject as a DataFrame
import pandas as pd
files_df = layout.to_df()
sub01_df = files_df[files_df["subject"] == "01"]
BIDS-Apps are containerized analysis pipelines that accept BIDS datasets as input:
# General BIDS-App invocation pattern
docker run -v /path/to/bids:/data:ro -v /path/to/output:/out \
<bids-app-image> /data /out participant --participant_label 01
# Common BIDS-Apps:
# fMRIPrep - fMRI preprocessing
docker run nipreps/fmriprep /data /out participant \
--participant-label 01 --fs-license-file /license.txt
# MRIQC - MRI quality control
docker run nipreps/mriqc /data /out participant \
--participant-label 01
# QSIPrep - diffusion MRI preprocessing
docker run pennbbl/qsiprep /data /out participant \
--participant-label 01
BIDS-App interface convention:
bids-app input_dataset output_dir {participant|group} [options]
participant level: runs per-subjectgroup level: runs across all subjects (aggregation/group stats)This skill includes detailed reference documentation:
Update schema and BEPs with: python scripts/update_schema.py
Cause: Missing dataset_description.json at the root.
Fix: Create the file with at minimum {"Name": "...", "BIDSVersion": "1.10.0"}.
Cause: Not all subjects have the same set of files (some missing sessions, runs, etc.).
Fix: This is a warning, not an error. Use --ignoreSubjectConsistency if intentional. Document missing data in participants.tsv or a scans.tsv.
Cause: dcm2niix couldn't extract slice timing from DICOM headers.
Fix: Determine slice order from the scan protocol and add manually to the JSON sidecar. Common patterns: ascending, descending, interleaved (odd-first or even-first).
Cause: Axis labels (i/j/k vs x/y/z vs LR/AP/SI) are confusing.
Fix: In BIDS, use NIfTI image axes: i=first axis, j=second, k=third. - means negative direction. For standard axial acquisitions: j is typically anterior-posterior. Verify with the acquisition protocol.
Cause: Full filesystem indexing on every BIDSLayout() call.
Fix: Use database_path to cache the index to an SQLite file:
layout = BIDSLayout("/data", database_path="/data/.pybids_cache.db")
Cause: Derivatives directory missing its own dataset_description.json.
Fix: Every derivatives directory must have dataset_description.json with "DatasetType": "derivative".
Cause: onset times are relative to the wrong reference (e.g., trigger time vs first volume).
Fix: Onsets must be in seconds relative to the first volume of that run's acquisition. Account for dummy scans if they were discarded.
Cause: Encoding or delimiter issues (spaces instead of tabs, BOM characters, Windows line endings).
Fix: Ensure tab-separated values with UTF-8 encoding and Unix line endings (\n). Use n/a (not NA, NaN, or empty) for missing values.
Validate early and often - Run the BIDS validator after every conversion or modification. Fix errors before they compound.
Use metadata inheritance - Place shared metadata (e.g., TaskName, scanner parameters) in top-level sidecar files rather than duplicating in every subject's directory.
Keep sourcedata - Store the original DICOM (or other raw) data under sourcedata/ so conversions are reproducible. Add sourcedata/ to .bidsignore.
Use consistent naming from the start - Define your BIDS naming scheme before data collection. Use the ReproIn naming convention for scan protocols to enable automatic conversion.
Document your dataset - Write a thorough README describing the study design, acquisition parameters, known issues, and any deviations from BIDS.
Use scans.tsv for run-level metadata - Record per-run acquisition times and quality notes:
filename acq_time quality
func/sub-01_task-rest_bold.nii.gz 2025-01-15T10:30:00 good
Version your dataset - Use CHANGES to document dataset modifications. Consider DataLad for full version control of large datasets.
Deface anatomical images - Remove facial features from T1w/T2w images before sharing (e.g., using pydeface, mri_deface, or afni_refacer). Store defaced versions as the primary data or use _defacemask files.
Use BIDS URIs for provenance - In derivatives, reference source files using BIDS URIs: bids::sub-01/anat/sub-01_T1w.nii.gz.
Prefer community tools - Use established BIDS-Apps (fMRIPrep, MRIQC, QSIPrep) rather than custom pipelines when possible. They handle BIDS I/O correctly and produce BIDS-compliant derivatives.
Study bids-examples - The bids-examples repository is the canonical collection of prototypical BIDS datasets covering different modalities and use cases (MRI, fMRI, DWI, EEG, MEG, iEEG, PET, ASL, genetics, derivatives, and more). Use it as a reference when structuring your own dataset, as test data for BIDS tools, or to understand how a specific modality should be organized. Each example passes the BIDS validator.
BEPs are community-driven proposals to extend BIDS to new modalities, derivatives, or metadata. The full list with status, leads, and links is in references/beps.yml (fetched from the bids-website). BEP-specific schema previews are rendered at https://github.com/bids-standard/bids-schema/tree/main/BEPs.
Current BEPs (as of schema update):
| BEP | Title | Content | Status |
|---|---|---|---|
| 004 | Susceptibility Weighted Imaging | raw | Seeking new leader |
| 011 | Structural preprocessing derivatives | derivative | Has PR (#518) |
| 012 | Functional preprocessing derivatives | derivative | Has PR (#519), schema implemented |
| 014 | Affine transforms and nonlinear field warps | derivative | X5 format development |
| 016 | Diffusion weighted imaging derivatives | derivative | Has PR (#2211) |
| 017 | Generic BIDS connectivity data schema | derivative | In development |
| 021 | Common Electrophysiological Derivatives | derivative | In development |
| 023 | PET Preprocessing derivatives | derivative | In development |
| 024 | Computed Tomography scan | raw | Seeking contributors |
| 026 | Microelectrode Recordings | raw | Seeking new leader |
| 028 | Provenance | metadata | Has PR (#2099) |
| 032 | Microelectrode electrophysiology | raw | Has PR (#2307), preview available — covers Neuropixels and other extracellular probes; relates to neuropixels-analysis skill |
| 033 | Advanced Diffusion Weighted Imaging | raw | Seeking contributors |
| 034 | Computational modeling | derivative | Has PR (#967) |
| 035 | Mega-analyses with non-compliant derivatives | derivative | In development |
| 036 | Phenotypic Data Guidelines | raw | Community review |
| 037 | Non-Invasive Brain Stimulation | raw | In development |
| 039 | Dimensionality reduction-based networks | raw | In development |
| 040 | Functional Ultrasound | raw | In development |
| 041 | Statistical Model Derivatives | derivative | Collecting feedback |
| 043 | BIDS Term Mapping | metadata | Collecting feedback |
| 044 | Stimuli | raw | Has PR (#2022), community review |
| 045 | Peripheral Physiological Recordings | raw | Has PR (#2267) |
| 046 | Diffusion Tractography | derivative | In development |
| 047 | Audio/video recordings for behavioral experiments | raw | Has PR (#2231) |
Related standards:
| Tool | Purpose |
|---|---|
| fMRIPrep | fMRI preprocessing (produces BIDS derivatives) |
| MRIQC | MRI quality control (produces BIDS derivatives) |
| QSIPrep | Diffusion MRI preprocessing |
| TemplateFlow | Neuroimaging templates and atlases with BIDS-like naming |
| Fitlins | BIDS Stats Models implementation |
| DataLad | Version control for large datasets, integrates with BIDS |
| OpenNeuro | Free BIDS dataset repository |
| DANDI | Neurophysiology data archive (uses BIDS for some modalities) |
| HeuDiConv | DICOM-to-BIDS with heuristic Python files |
| dcm2bids | DICOM-to-BIDS with JSON config |
| BIDScoin | DICOM-to-BIDS with GUI and YAML config |
| nwb2bids | Convert NWB (Neurodata Without Borders) files to BIDS |
| CuBIDS | BIDS dataset curation and harmonization |
| bids2table | Efficient tabular indexing of BIDS datasets |
| bids-examples | Canonical collection of prototypical BIDS datasets for all modalities |