LibriVox Mirror: A Public-Domain Audiobook Dataset on Hugging Face

James Ding · Posted on

LibriVox volunteers record public-domain books and give the audio away. The Internet Archive hosts it. They have been doing this for more than 20 years.1

I wanted to use the collection in large audio jobs. The Internet Archive is an excellent archive, but repeatedly walking half a million MP3s is a rough input pipeline.

So that’s what LibriVox Mirror is for. It keeps the original MP3s, packs each book into a streamable WebDataset TAR, and adds typed Parquet indexes for books and audio segments.

I guess the main point is convenience: the mirror gives you LibriVox already organized and fast to stream from Hugging Face, without another crawl through the Internet Archive.

At the time of this build: 21,644 books, 491,026 segments, 131,973 hours, and 7.58 TB.2

Here is the collection by Internet Archive publication date, in a GitHub-esque contribution graph.3

JanFebMarAprMayJunJulAugSepOctNovDec
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026

Mirrored LibriVox audio segments by Internet Archive publication year
YearSegments
2005282
20065491
200714648
200817346
200922477
201022262
201123326
201223204
201323680
201420865
201523165
201624569
201727607
201824963
201925928
202032614
202132147
202229702
202329390
202427858
202523338
202616164

Every sample keeps its LibriVox project, exact Internet Archive source file, upstream checksums, and a mirror SHA-256.4 Records with missing or contradictory source files are quarantined instead of guessed.5

A scheduled sync picks up new books as LibriVox publishes them. The dataset is on Hugging Face, and the mirroring tool is open source.

Footnotes

  1. LibriVox accepts readers without auditions or prior recording experience. The project says it has no paid staff, board, or offices. See how volunteering works and its note to donors.
  2. Book, segment, and duration totals come from the mirror’s versioned state/sync.json. Storage comes from Hugging Face repository usage. Both are fetched at build time.
  3. The grid reads each book’s exact section_count and archive_metadata.publicdate, then groups those segments into seven-day blocks and three-hour UTC windows. It measures when the containing book became public, not when somebody narrated it. The data is refreshed at build time, with a last-known snapshot as fallback.
  4. The mirror is a downstream cache, not a replacement for either project. The source links and checksums make every file traceable to the original.
  5. Typical failures are a missing Archive item or metadata naming an MP3 that does not exist.