OpenedAI API for audio/speech
-----------------------------

This is an API clone of the OpenAI API for text to speech audio generation.

* Compatible with the OpenAI audio/speech API
* Does not connect to the OpenAI API and does not require a (real) OpenAI API Key
* Not affiliated with OpenAI in any way

Full Compatibility:
* `tts-1`: `alloy`, `echo`, `fable`, `onyx`, `nova`, and `shimmer` (configurable)
* `tts-1-hd`:  `alloy`, `echo`, `fable`, `onyx`, `nova`, and `shimmer` (configurable, uses OpenAI samples by default)
* response_format: `mp3`, `opus`, `aac`, or `flac`
* speed 0.25-4.0 (and more)

Details:
* model 'tts-1' via [piper tts](https://github.com/rhasspy/piper) (fast, can use cpu)
* model 'tts-1-hd' via [coqui-ai/TTS](https://github.com/coqui-ai/TTS) xtts_v2 voice cloning (fast, uses almost 4GB GPU VRAM)
* Can be run without TTS/xtts_v2, entirely on cpu
* Custom cloned voices can be used for tts-1-hd, just save a WAV file in `/voices/`
* You can map your own [piper voices](https://rhasspy.github.io/piper-samples/) and xtts_v2 speaker clones via `voice_to_speaker.yaml`
* Sometimes certain words or symbols will sound bad, you can fix them with regex via `pre_process_map.yaml`

If you find a better voice match for `tts-1` or `tts-1-hd`, please let me know so I can update the defaults.

Version: 0.2.0

Last update: 2023-11-27

API Documentation
-----------------

* [OpenAI Text to speech guide](https://platform.openai.com/docs/guides/text-to-speech)
* [OpenAI API Reference](https://platform.openai.com/docs/api-reference/audio/createSpeech)


Installation instructions
-------------------------

```shell
# Install the Python requirements
pip install -r requirements.txt
# install ffmpeg
sudo apt install ffmpeg
# Download the voice models:
# for tts-1
bash download_voices_tts-1.sh
# and for tts-1-hd
bash download_voices_tts-1-hd.sh
```

Usage
-----

```
usage: main.py [-h] [--piper_cuda] [--xtts_device XTTS_DEVICE] [--preload_xtts] [-P PORT] [-H HOST]

OpenedAI Speech API Server

options:
  -h, --help            show this help message and exit
  --piper_cuda          Enable cuda for piper. Note: --cuda/onnxruntime-gpu is not working for me, but cpu is fast enough (default: False)
  --xtts_device XTTS_DEVICE
                        Set the device for the xtts model. The special value of 'none' will use piper for all models. (default: cuda)
  --preload_xtts        Preload the xtts model. By default it's loaded on first use. (default: False)
  -P PORT, --port PORT  Server tcp port (default: 8000)
  -H HOST, --host HOST  Host to listen on, Ex. 0.0.0.0 (default: localhost)
```

Sample API Usage
----------------

You can use it like this:

```shell
curl http://localhost:8000/v1/audio/speech -H "Content-Type: application/json" -d '{
    "model": "tts-1",
    "input": "The quick brown fox jumped over the lazy dog.",
    "voice": "alloy",
    "response_format": "mp3",
    "speed": 1.0
  }' > speech.mp3
```

Or just like this:

```shell
curl http://localhost:8000/v1/audio/speech -H "Content-Type: application/json" -d '{
    "input": "The quick brown fox jumped over the lazy dog."}' > speech.mp3
```

Or like this example from the [OpenAI Text to speech guide](https://platform.openai.com/docs/guides/text-to-speech):

```python
import openai

client = openai.OpenAI(
  # This part is not needed if you set these environment variables before import openai
  # export OPENAI_API_KEY=sk-11111111111
  # export OPENAI_BASE_URL=http://localhost:8000/v1
  api_key = "sk-111111111",
  base_url = "http://localhost:8000/v1",
)

response = client.audio.speech.create(
  model="tts-1",
  voice="alloy",
  input="Today is a wonderful day to build something people love!"
)

response.stream_to_file("speech.mp3")
```

Docker support
--------------

You can run the server via docker like so:
```shell
docker compose build
docker compose up
```

If you want a minimal docker image with piper only (see: Dockerfile.min). You can edit the `docker-compose.yml` to change this.