# What does this PR do?

Until recently, there was only one TTS model in Transformers. Recent ([Bark](https://huggingface.co/docs/transformers/model_doc/bark)) and future ([FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439)) additions have and will further enrich the number of TTS models in Transformers. 
This may be the best time to add a text-to-speech pipeline to Transformers.

This PR tentatively proposes:

- The addition of a text-to-speech pipeline whose design could be modified in line with future TTS additions.
- Add a class AutoModelForTextToSpeech
- Add a `processor` task to the pipeline code to facilitate use of the `processor`.

My conception of the architecture for now:

- Backward compatibility with [FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439), retaining the ability to use its hacked `generate_speech` method.
- Future compatibility with future TTS models, counting on the fact that these models will use a `generate` method to generate audio.
- Possible compatibility with other TTA (text-to-audio) models such as [MusicGen](https://huggingface.co/docs/transformers/model_doc/musicgen).

What I'm counting on:
- future models should have a `generate` method, even if they are not AR models per se (for the moment, [FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439) is not AR and has no such method) or counts on an additional head model ([FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439) needs a vocoder on top to pass from a spectrogram to an audio - see [discussion here](https://github.com/huggingface/transformers/pull/23439#discussion_r1258660411)).
- future models will use a `Processor` even if they only use a tokenizer, to allow easy use of other conditional inputs such as audio or speaker embeddings.  And the processor must be added to `PROCESSOR_MAPPING` (not the case of [MusicGen](https://huggingface.co/docs/transformers/model_doc/musicgen) atm).

I'm open to further discuss the architecture and to make some changes!

EDIT: for reference, I've made another design choice following internal discussions. It is discussed [here](https://github.com/huggingface/transformers/pull/24952/#pullrequestreview-1556507240).

Fixes #22487

*Note:* I was inspired by @LysandreJik draft of a [TTS pipeline](https://huggingface.co/lysandre/text-to-speech-pipeline/blob/main/tts.py).

## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
- [x] Did you read the [contributor guideline](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md#start-contributing-pull-requests),
      Pull Request section?
- [x] Was this discussed/approved via a Github issue or the [forum](https://discuss.huggingface.co/)? [LINK](https://github.com/huggingface/transformers/issues/22487#issuecomment-1496312713)
- [ ] Did you make sure to update the documentation with your changes? Here are the
      [documentation guidelines](https://github.com/huggingface/transformers/tree/main/docs), and
      [here are tips on formatting docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [x] Did you write any new necessary tests?


## Who can review?

Hey @sanchit-gandhi and @Narsil, I think you're the right people to talk to before the core review!

Add Text-To-Speech pipeline. # What does this PR do?

Until recently, there was only one TTS model in Transformers. Recent ([Bark](https://huggingface.co/docs/transformers/model_doc/bark)) and future ([FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439)) additions have and will further enrich the number of TTS models in Transformers. 
This may be the best time to add a text-to-speech pipeline to Transformers.

This PR tentatively proposes:

- The addition of a text-to-speech pipeline whose design could be modified in line with future TTS additions.
- Add a class AutoModelForTextToSpeech
- Add a `processor` task to the pipeline code to facilitate use of the `processor`.

My conception of the architecture for now:

- Backward compatibility with [FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439), retaining the ability to use its hacked `generate_speech` method.
- Future compatibility with future TTS models, counting on the fact that these models will use a `generate` method to generate audio.
- Possible compatibility with other TTA (text-to-audio) models such as [MusicGen](https://huggingface.co/docs/transformers/model_doc/musicgen).

What I'm counting on:
- future models should have a `generate` method, even if they are not AR models per se (for the moment, [FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439) is not AR and has no such method) or counts on an additional head model ([FastSpeechConformer2](https://github.com/huggingface/transformers/pull/23439) needs a vocoder on top to pass from a spectrogram to an audio - see [discussion here](https://github.com/huggingface/transformers/pull/23439#discussion_r1258660411)).
- future models will use a `Processor` even if they only use a tokenizer, to allow easy use of other conditional inputs such as audio or speaker embeddings.  And the processor must be added to `PROCESSOR_MAPPING` (not the case of [MusicGen](https://huggingface.co/docs/transformers/model_doc/musicgen) atm).

I'm open to further discuss the architecture and to make some changes!

EDIT: for reference, I've made another design choice following internal discussions. It is discussed [here](https://github.com/huggingface/transformers/pull/24952/#pullrequestreview-1556507240).

Fixes #22487

*Note:* I was inspired by @LysandreJik draft of a [TTS pipeline](https://huggingface.co/lysandre/text-to-speech-pipeline/blob/main/tts.py).

## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
- [x] Did you read the [contributor guideline](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md#start-contributing-pull-requests),
      Pull Request section?
- [x] Was this discussed/approved via a Github issue or the [forum](https://discuss.huggingface.co/)? [LINK](https://github.com/huggingface/transformers/issues/22487#issuecomment-1496312713)
- [ ] Did you make sure to update the documentation with your changes? Here are the
      [documentation guidelines](https://github.com/huggingface/transformers/tree/main/docs), and
      [here are tips on formatting docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [x] Did you write any new necessary tests?


## Who can review?

Hey @sanchit-gandhi and @Narsil, I think you're the right people to talk to before the core review!

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# Run training on Amazon SageMaker

The documentation has been moved to [hf.co/docs/sagemaker](https://huggingface.co/docs/sagemaker). This page will be removed in `transformers` 5.0. 

### Table of Content

- [Train Hugging Face models on Amazon SageMaker with the SageMaker Python SDK](https://huggingface.co/docs/sagemaker/train)
- [Deploy Hugging Face models to Amazon SageMaker with the SageMaker Python SDK](https://huggingface.co/docs/sagemaker/inference)
- [Frequently Asked Questions](https://huggingface.co/docs/sagemaker/faq)

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Copyright 2020 The HuggingFace Team. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

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distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

⚠️ Note that this file is in Markdown but contain specific syntax for our doc-builder (similar to MDX) that may not be
rendered properly in your Markdown viewer.

-->

# Run training on Amazon SageMaker

The documentation has been moved to [hf.co/docs/sagemaker](https://huggingface.co/docs/sagemaker). This page will be removed in `transformers` 5.0. 

### Table of Content

- [Train Hugging Face models on Amazon SageMaker with the SageMaker Python SDK](https://huggingface.co/docs/sagemaker/train)
- [Deploy Hugging Face models to Amazon SageMaker with the SageMaker Python SDK](https://huggingface.co/docs/sagemaker/inference)
- [Frequently Asked Questions](https://huggingface.co/docs/sagemaker/faq)
