rokaijano/extracel_waveforms

Spike waveform shards (derived from IBL dandiset 000409)

A curated collection of per-spike multichannel waveform windows extracted from NWB assets in the DANDI dandiset 000409 (International Brain Laboratory, IBL). This repository contains the extractor and uploader used to produce Parquet shards; this README documents the derived dataset, its provenance, format, and how to reproduce it.

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Short description

Parquet shards of spike waveform windows (channels × timesteps). Each row contains a fixed-shape multichannel waveform centered on a spike and related metadata (recording URI, unit identifier, spike time, channel indices, and extraction metadata). The dataset is intended for ML and analysis workflows operating on per-spike waveforms.

Source / provenance

• Primary source: DANDI Archive, Dandiset 000409 (International Brain Laboratory). See: https://dandiarchive.org/dandiset/000409
• The list of candidate NWB asset URIs used during extraction is stored here: feature_extractor/dandi_downloader/dandi_list.txt
• Note: not every URI in that list was necessarily processed — the Hugging Face dataset contains the subset of assets that were successfully downloaded and extracted.

Original dandiset summary (selected fields):

• Title: IBL - Brain Wide Map [deprecated]
• ID: 000409
• License: spdx:CC-BY-4.0 (verify per-asset license/metadata)
• Related resource: https://doi.org/10.1101/2023.07.04.547681

Refer to the original DANDI page for the full contributor list, asset-level metadata, and licensing details.

What the dataset contains

• File type: Parquet (.parquet) shards (row-wise shards; default shard_rows=10000 in the extractor).
• Typical per-row fields (inspect shards to confirm exact schema):
  • recording_uri — original NWB/DANDI URI
  • unit_id — identifier for the unit within the NWB
  • spike_time — spike time in seconds
  • waveform — array/tensor (channels × timesteps)
  • peak_channel / channel_indices — channels included in the window
  • extraction metadata: sampling rate, sample index, extractor params (when present)

Notes:

• The extractor performs minimal filtering by default (no normalization, no SNR filtering) unless explicitly configured.
• Check a sample shard with pyarrow or pandas to confirm exact field names and dtypes.

How the dataset was produced

• Workflow overview:
  1. Download NWB asset (via dandi CLI, S3, or direct HTTP after resolving dandi:// URIs).
  2. Open NWB/HDF5, locate ElectricalSeries and unit spike times/metadata.
  3. For each spike, compute corresponding sample index (or use timestamps) and extract a fixed-size waveform window centered on the spike at the unit's peak channel.
  4. Pad/truncate windows at edges to ensure a fixed (channels, timesteps) shape.
  5. Aggregate rows and write Parquet shards.
  6. Optionally upload shards using the uploader helper.

Typical extraction parameters (defaults)

• channels: 25
• timesteps: 300
• shard_rows: 10000
• compression: zstd
• max_spikes_per_unit: 500

Actual dataset shards may have been produced with different parameter overrides; inspect the shard metadata or the extractor run logs for precise parameters used.

Data licensing and attribution

• This dataset is a derived product of NWB assets hosted on DANDI. Users must comply with the license and attribution requirements of the original assets. The dandiset lists spdx:CC-BY-4.0, but please verify per-asset metadata on DANDI for any variations.
• When using or publishing results based on these shards, cite the original DANDI dandiset and the related IBL publication.

Citation

Please cite:

• International Brain Laboratory — DANDI Dandiset 000409. https://dandiarchive.org/dandiset/000409
• A Brain-Wide Map of Neural Activity during Complex Behaviour (preprint): https://doi.org/10.1101/2023.07.04.547681

If you use the Hugging Face dataset derived from these shards, also cite the HF dataset page (include the HF dataset identifier and URL)

Inspecting shards / example

Load a shard with pandas / pyarrow:

import pyarrow.parquet as pq
import pandas as pd

tbl = pq.read_table('/path/to/shard_00000.parquet')
df = tbl.to_pandas()
print(df.columns)
print(df.iloc[0])

Last updated: 2026-02-02