# UWSpeech: Speech to Speech Translation for Unwritten Languages

arXiv: https://arxiv.org/abs/2006.07926 · HTML: https://mlsanity.com/paper/2006.07926/

## Key facts

- Cited by 43 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 14 Jun 2020.

## Built on by (most cited first, 30 of 43)

- [VoxPopuli: A Large-Scale Multilingual Speech Corpus for Representation Learning, Semi-Supervised Learning and Interpretation](https://mlsanity.com/paper/2101.00390/) (2021)
- [AudioPaLM: A Large Language Model That Can Speak and Listen](https://mlsanity.com/paper/2306.12925/) (2023)
- [A Survey on Neural Speech Synthesis](https://mlsanity.com/paper/2106.15561/) (2021)
- [Direct speech-to-speech translation with discrete units](https://mlsanity.com/paper/2107.05604/) (2021)
- [Textless Speech-to-Speech Translation on Real Data](https://mlsanity.com/paper/2112.08352/) (2021)
- [Translatotron 2: High-quality direct speech-to-speech translation with voice preservation](https://mlsanity.com/paper/2107.08661/) (2021)
- [CVSS Corpus and Massively Multilingual Speech-to-Speech Translation](https://mlsanity.com/paper/2201.03713/) (2022)
- [UnitY: Two-pass Direct Speech-to-speech Translation with Discrete Units](https://mlsanity.com/paper/2212.08055/) (2022)
- [Enhanced Direct Speech-to-Speech Translation Using Self-supervised Pre-training and Data Augmentation](https://mlsanity.com/paper/2204.02967/) (2022)
- [Recent Advances in Discrete Speech Tokens: A Review](https://mlsanity.com/paper/2502.06490/) (2025)
- [TranSpeech: Speech-to-Speech Translation With Bilateral Perturbation](https://mlsanity.com/paper/2205.12523/) (2022)
- [Speech-to-Speech Translation For A Real-world Unwritten Language](https://mlsanity.com/paper/2211.06474/) (2022)
- [Variable-rate discrete representation learning](https://mlsanity.com/paper/2103.06089/) (2021)
- [Leveraging unsupervised and weakly-supervised data to improve direct speech-to-speech translation](https://mlsanity.com/paper/2203.13339/) (2022)
- [Textless Direct Speech-to-Speech Translation with Discrete Speech Representation](https://mlsanity.com/paper/2211.00115/) (2022)
- [PolyVoice: Language Models for Speech to Speech Translation](https://mlsanity.com/paper/2306.02982/) (2023)
- [DUB: Discrete Unit Back-translation for Speech Translation](https://mlsanity.com/paper/2305.11411/) (2023)
- [A Survey on Low-Resource Neural Machine Translation](https://mlsanity.com/paper/2107.04239/) (2021)
- [Leveraging Pseudo-labeled Data to Improve Direct Speech-to-Speech Translation](https://mlsanity.com/paper/2205.08993/) (2022)
- [Translatotron 3: Speech to Speech Translation with Monolingual Data](https://mlsanity.com/paper/2305.17547/) (2023)
- [Assessing Evaluation Metrics for Speech-to-Speech Translation](https://mlsanity.com/paper/2110.13877/) (2021)
- [ESPnet-ST-v2: Multipurpose Spoken Language Translation Toolkit](https://mlsanity.com/paper/2304.04596/) (2023)
- [Joint Pre-Training with Speech and Bilingual Text for Direct Speech to Speech Translation](https://mlsanity.com/paper/2210.17027/) (2022)
- [DASpeech: Directed Acyclic Transformer for Fast and High-quality Speech-to-Speech Translation](https://mlsanity.com/paper/2310.07403/) (2023)
- [UniSS: Unified Expressive Speech-to-Speech Translation with Your Voice](https://mlsanity.com/paper/2509.21144/) (2025)
- [AV-TranSpeech: Audio-Visual Robust Speech-to-Speech Translation](https://mlsanity.com/paper/2305.15403/) (2023)
- [Towards cross-language prosody transfer for dialog](https://mlsanity.com/paper/2307.04123/) (2023)
- [TMT: Tri-Modal Translation between Speech, Image, and Text by Processing Different Modalities as Different Languages](https://mlsanity.com/paper/2402.16021/) (2024)
- [TransFace: Unit-Based Audio-Visual Speech Synthesizer for Talking Head Translation](https://mlsanity.com/paper/2312.15197/) (2023)
- [Can We Achieve High-quality Direct Speech-to-Speech Translation without Parallel Speech Data?](https://mlsanity.com/paper/2406.07289/) (2024)

## Abstract (arXiv)

Existing speech to speech translation systems heavily rely on the text of target language: they usually translate source language either to target text and then synthesize target speech from text, or directly to target speech with target text for auxiliary training. However, those methods cannot be applied to unwritten target languages, which have no written text or phoneme available. In this paper, we develop a translation system for unwritten languages, named as UWSpeech, which converts target unwritten speech into discrete tokens with a converter, and then translates source-language speech into target discrete tokens with a translator, and finally synthesizes target speech from target discrete tokens with an inverter. We propose a method called XL-VAE, which enhances vector quantized variational autoencoder (VQ-VAE) with cross-lingual (XL) speech recognition, to train the converter and inverter of UWSpeech jointly. Experiments on Fisher Spanish-English conversation translation dataset show that UWSpeech outperforms direct translation and VQ-VAE baseline by about 16 and 10 BLEU points respectively, which demonstrate the advantages and potentials of UWSpeech.
