# Deciphering Speech: a Zero-Resource Approach to Cross-Lingual Transfer in ASR

arXiv: https://arxiv.org/abs/2111.06799 · HTML: https://mlsanity.com/paper/2111.06799/

## Key facts

- Cited by 11 papers in the map (data through 14 Oct 2026).
- Builds on 10 of its 45 references that are in the map.
- First posted on arXiv 12 Nov 2021.

## Builds on (most cited first, 10 of 10)

- [wav2vec 2.0: A Framework for Self-Supervised Learning of Speech Representations](https://mlsanity.com/paper/2006.11477/) (2020)
- [Listen, Attend and Spell](https://mlsanity.com/paper/1508.01211/) (2015)
- [Unsupervised Speech Recognition](https://mlsanity.com/paper/2105.11084/) (2021)
- [Universal Phone Recognition with a Multilingual Allophone System](https://mlsanity.com/paper/2002.11800/) (2020)
- [A segmental framework for fully-unsupervised large-vocabulary speech recognition](https://mlsanity.com/paper/1606.06950/) (2016)
- [Multilingual Graphemic Hybrid ASR with Massive Data Augmentation](https://mlsanity.com/paper/1909.06522/) (2019)
- [How Phonotactics Affect Multilingual and Zero-shot ASR Performance](https://mlsanity.com/paper/2010.12104/) (2020)
- [Multilingual and Unsupervised Subword Modeling for Zero-Resource Languages](https://mlsanity.com/paper/1811.04791/) (2018)
- [Lattice-based lightly-supervised acoustic model training](https://mlsanity.com/paper/1905.13150/) (2019)
- [Learning to Pronounce Chinese Without a Pronunciation Dictionary](https://mlsanity.com/paper/2010.04744/) (2020)

## Built on by (most cited first, 11 of 11)

- [Self-Supervised Speech Representation Learning: A Review](https://mlsanity.com/paper/2205.10643/) (2022)
- [Learning from Flawed Data: Weakly Supervised Automatic Speech Recognition](https://mlsanity.com/paper/2309.15796/) (2023)
- [Zero-resource Speech Translation and Recognition with LLMs](https://mlsanity.com/paper/2412.18566/) (2024)
- [A Theory of Unsupervised Speech Recognition](https://mlsanity.com/paper/2306.07926/) (2023)
- [Pronunciation-Lexicon Free Training for Phoneme-based Crosslingual ASR via Joint Stochastic Approximation](https://mlsanity.com/paper/2507.06249/) (2025)
- [Acoustic Word Embeddings for Untranscribed Target Languages with Continued Pretraining and Learned Pooling](https://mlsanity.com/paper/2306.02153/) (2023)
- [Improving grapheme-to-phoneme conversion by learning pronunciations from speech recordings](https://mlsanity.com/paper/2307.16643/) (2023)
- [Towards Unsupervised Speech Recognition Without Pronunciation Models](https://mlsanity.com/paper/2406.08380/) (2024)
- [Unsupervised ASR via Cross-Lingual Pseudo-Labeling](https://mlsanity.com/paper/2305.13330/) (2023)
- [MUST: A Multilingual Student-Teacher Learning approach for low-resource speech recognition](https://mlsanity.com/paper/2310.18865/) (2023)
- [Modeling Overlapped Speech with Shuffles](https://mlsanity.com/paper/2603.17769/) (2026)

## Abstract (arXiv)

We present a method for cross-lingual training an ASR system using absolutely no transcribed training data from the target language, and with no phonetic knowledge of the language in question. Our approach uses a novel application of a decipherment algorithm, which operates given only unpaired speech and text data from the target language. We apply this decipherment to phone sequences generated by a universal phone recogniser trained on out-of-language speech corpora, which we follow with flat-start semi-supervised training to obtain an acoustic model for the new language. To the best of our knowledge, this is the first practical approach to zero-resource cross-lingual ASR which does not rely on any hand-crafted phonetic information. We carry out experiments on read speech from the GlobalPhone corpus, and show that it is possible to learn a decipherment model on just 20 minutes of data from the target language. When used to generate pseudo-labels for semi-supervised training, we obtain WERs that range from 32.5% to just 1.9% absolute worse than the equivalent fully supervised models trained on the same data.
