---
license: cc-by-sa-4.0
language: [en, de, es]
pretty_name: "ODSS — An Open Dataset of Synthetic Speech"
task_categories: [audio-classification]
size_categories: [10K<n<100K]
configs:
  - config_name: default
    data_files:
      - {split: test, path: "data/test-*.parquet"}
tags:
  - anti-spoofing
  - audio-deepfake-detection
  - speech
  - benchmark
  - arena-ready
  - synthetic-speech
  - multilingual
arxiv: ["10.5281/zenodo.8370669"]
---

# ODSS — An Open Dataset of Synthetic Speech

Benchmark-ready packaging of **ODSS** (*An Open Dataset of Synthetic Speech*), a
multilingual (English / German / Spanish), multispeaker dataset for **synthetic
speech detection**: each natural utterance is paired with TTS re-synthesis of the
same text.

## Overview

Binary classification: **bonafide** (natural human recordings) vs. **spoof**
(text-to-speech). The synthetic side is generated by two TTS systems — the
end-to-end **VITS** architecture and a two-step **FastPitch + HiFi-GAN** pipeline —
over 156 voices spanning three languages with balanced gender. Label is the
top-level generator directory: `natural/` → bonafide, `vits/` and
`fastpitch-hifigan/` → spoof.

### Source corpora — VCTK-derived and others

ODSS draws its speech from four public corpora (this is a **VCTK-based** dataset
among others):

| Corpus | Language | Role |
|--------|----------|------|
| **VCTK** | English | English **VITS** voices (`vits/vctk`) |
| **Hi-Fi TTS** | English | natural + VITS + FastPitch |
| **HUI-audio-corpus-german** | German | natural + VITS + FastPitch |
| **OpenSLR Spanish** | Spanish | natural + VITS + FastPitch |

Note: the `vits/vctk` synthetic clips (English) are present on the **spoof** side;
their natural VCTK counterparts are distributed separately by the VCTK project and
are not part of this release.

## License & redistribution

Released under the **Creative Commons Attribution-ShareAlike 4.0 International
(CC BY-SA 4.0)** license — the license shipped in the upstream ODSS `LICENSE` file.
Redistribution and adaptation are permitted with attribution and ShareAlike (this
packaging is itself CC BY-SA 4.0). Audio is the original 16 kHz mono WAV, embedded
bit-exactly (no re-encode — a full decode probe of all 26,954 clips passed cleanly).
See `LICENSE.txt`. Attribute the ODSS authors and the four source corpora.

## Schema

| Column | Type | Description |
|--------|------|-------------|
| `path` | `string` | source-relative path, e.g. `vits/vctk/p293/p293_168.wav`, unique |
| `audio` | `Audio(16000)` | 16 kHz mono WAV |
| `label` | `ClassLabel` | `"bonafide"` (0) / `"spoof"` (1) |
| `notes` | `string` | JSON: `utterance_id`, `generator`, `source_corpus`, `speaker`, `language`, `attack` |

`notes` example:
```json
{"utterance_id": "vits__vctk__p293__p293_168", "generator": "vits", "source_corpus": "vctk", "speaker": "p293", "language": "en", "attack": "vits"}
```

`utterance_id` is the full source-relative path with `/` → `__` — the bare stem
repeats across the three generators (the same texts are synthesized), so the
generator prefix is what makes ids unique.

## Quick Start

```python
from datasets import load_dataset

ds = load_dataset("SpeechAntiSpoofingBenchmarks/ODSS", split="test")
print(ds[0])
```

## Stats

| Stat | Value |
|------|-------|
| Total trials | 26,954 |
| Bonafide (natural) | 7,961 |
| Spoof (TTS) | 18,993 |
| — VITS | 11,032 |
| — FastPitch + HiFi-GAN | 7,961 |
| Languages | en (14,405), de (5,778), es (6,771) |
| Source corpora | VCTK, Hi-Fi TTS, HUI-de, OpenSLR-ES |

## Source provenance

- Paper: *An Open Dataset of Synthetic Speech*, IEEE, 2023.
  https://ieeexplore.ieee.org/document/10374863/
- Dataset: https://zenodo.org/records/8370669 (DOI 10.5281/zenodo.8370669)
- Project: vera.ai / Fraunhofer IDMT.

## Evaluation

For evaluation instructions and submission format, see [`submissions/README.md`](submissions/README.md).

## Citation

```bibtex
@inproceedings{odss2023,
  title     = {{An Open Dataset of Synthetic Speech}},
  booktitle = {Proc. IEEE Workshop},
  year      = {2023},
  doi       = {10.5281/zenodo.8370669},
  note      = {ODSS, https://ieeexplore.ieee.org/document/10374863/},
}
```

## Maintainer

Contact: k.n.borodin@mtuci.ru