transformers/docs/source/en/model_doc/unispeech.mdx

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# UniSpeech

## Overview

The UniSpeech model was proposed in [UniSpeech: Unified Speech Representation Learning with Labeled and Unlabeled Data](https://arxiv.org/abs/2101.07597) by Chengyi Wang, Yu Wu, Yao Qian, Kenichi Kumatani, Shujie Liu, Furu Wei, Michael
Zeng, Xuedong Huang .

The abstract from the paper is the following:

*In this paper, we propose a unified pre-training approach called UniSpeech to learn speech representations with both
unlabeled and labeled data, in which supervised phonetic CTC learning and phonetically-aware contrastive
self-supervised learning are conducted in a multi-task learning manner. The resultant representations can capture
information more correlated with phonetic structures and improve the generalization across languages and domains. We
evaluate the effectiveness of UniSpeech for cross-lingual representation learning on public CommonVoice corpus. The
results show that UniSpeech outperforms self-supervised pretraining and supervised transfer learning for speech
recognition by a maximum of 13.4% and 17.8% relative phone error rate reductions respectively (averaged over all
testing languages). The transferability of UniSpeech is also demonstrated on a domain-shift speech recognition task,
i.e., a relative word error rate reduction of 6% against the previous approach.*

Tips:

- UniSpeech is a speech model that accepts a float array corresponding to the raw waveform of the speech signal. Please
  use [`Wav2Vec2Processor`] for the feature extraction.
- UniSpeech model can be fine-tuned using connectionist temporal classification (CTC) so the model output has to be
  decoded using [`Wav2Vec2CTCTokenizer`].

This model was contributed by [patrickvonplaten](https://huggingface.co/patrickvonplaten). The Authors' code can be
found [here](https://github.com/microsoft/UniSpeech/tree/main/UniSpeech).

## Documentation resources

- [Audio classification task guide](../tasks/audio_classification)
- [Automatic speech recognition task guide](../tasks/asr)

## UniSpeechConfig

[[autodoc]] UniSpeechConfig

## UniSpeech specific outputs

[[autodoc]] models.unispeech.modeling_unispeech.UniSpeechForPreTrainingOutput

## UniSpeechModel

[[autodoc]] UniSpeechModel
    - forward

## UniSpeechForCTC

[[autodoc]] UniSpeechForCTC
    - forward

## UniSpeechForSequenceClassification

[[autodoc]] UniSpeechForSequenceClassification
    - forward

## UniSpeechForPreTraining

[[autodoc]] UniSpeechForPreTraining
    - forward