A fast, local neural text to speech system that sounds great and is optimized for the Raspberry Pi 4. Piper is used in a variety of projects.
echo 'Welcome to the world of speech synthesis!' | \
./piper --model en_US-lessac-medium.onnx --output_file welcome.wav
Listen to voice samples and check out a video tutorial by Thorsten Müller
Voices are trained with VITS and exported to the onnxruntime.
This is a project of the Open Home Foundation.
Our goal is to support Home Assistant and the Year of Voice.
Download voices for the supported languages:
You will need two files per voice:
.onnx
model file, such as en_US-lessac-medium.onnx
.onnx.json
config file, such as en_US-lessac-medium.onnx.json
The MODEL_CARD
file for each voice contains important licensing information. Piper is intended for text to speech research, and does not impose any additional restrictions on voice models. Some voices may have restrictive licenses, however, so please review them carefully!
You can run Piper with Python or download a binary release:
If you want to build from source, see the Makefile and C++ source.
You must download and extract piper-phonemize to lib/Linux-$(uname -m)/piper_phonemize
before building.
For example, lib/Linux-x86_64/piper_phonemize/lib/libpiper_phonemize.so
should exist for AMD/Intel machines (as well as everything else from libpiper_phonemize-amd64.tar.gz
).
.onnx
and .onnx.json
filespiper
binary with text on standard input, --model /path/to/your-voice.onnx
, and --output_file output.wav
For example:
echo 'Welcome to the world of speech synthesis!' | \
./piper --model en_US-lessac-medium.onnx --output_file welcome.wav
For multi-speaker models, use --speaker <number>
to change speakers (default: 0).
See piper --help
for more options.
Piper can stream raw audio to stdout as its produced:
echo 'This sentence is spoken first. This sentence is synthesized while the first sentence is spoken.' | \
./piper --model en_US-lessac-medium.onnx --output-raw | \
aplay -r 22050 -f S16_LE -t raw -
This is raw audio and not a WAV file, so make sure your audio player is set to play 16-bit mono PCM samples at the correct sample rate for the voice.
The piper
executable can accept JSON input when using the --json-input
flag. Each line of input must be a JSON object with text
field. For example:
{ "text": "First sentence to speak." }
{ "text": "Second sentence to speak." }
Optional fields include:
speaker
- string
speaker_id_map
in config (multi-speaker voices only)speaker_id
- number
output_file
- string
The following example writes two sentences with different speakers to different files:
{ "text": "First speaker.", "speaker_id": 0, "output_file": "/tmp/speaker_0.wav" }
{ "text": "Second speaker.", "speaker_id": 1, "output_file": "/tmp/speaker_1.wav" }
Piper has been used in the following projects/papers:
See the training guide and the source code.
Pretrained checkpoints are available on Hugging Face
See src/python_run
Install with pip
:
pip install piper-tts
and then run:
echo 'Welcome to the world of speech synthesis!' | piper \
--model en_US-lessac-medium \
--output_file welcome.wav
This will automatically download voice files the first time they're used. Use --data-dir
and --download-dir
to adjust where voices are found/downloaded.
If you'd like to use a GPU, install the onnxruntime-gpu
package:
.venv/bin/pip3 install onnxruntime-gpu
and then run piper
with the --cuda
argument. You will need to have a functioning CUDA environment, such as what's available in NVIDIA's PyTorch containers.