Adding piper module and voices to Speech Dispatcher for Web Speech API

piper-web-speech-api.md

An option for using piper and onnx voices in the browser is through Speech Dispatcher, which Chromium-based browsers (Chrome, Brave, Opera, Edge) and Firefox use for Web Speech API.

I have added the piper module to Speech Dispatcher following the instructions here module request: piper #866.

Tested on Chromium Version 128.0.6586.0 (Developer Build) (64-bit) and Firefox Nightly 130.0a1. Chromium works. Firefox does not load the piper voices.

In pertinent part.

Download the piper executable from releases, extract the contents and save to ~/.local/opt/piper.

Download a couple .onnx files and save to ~/.local/share/piper/voices.

Create a symbolic link to piper executable in ~/.local/bin, ln -s ~/.local/opt/piper/piper piper.

Install python3-speechd

sudo apt install python3-speechd
spd-conf -u

Modify ~/.config/speech-dispatcher/speechd.conf to add the piper module

 AddModule "piper"                     "sd_generic"   "piper.conf"

or set piper as the default module

 DefaultModule espeak-ng
 # piper

Create ~/.config/speech-dispatcher/modules/piper.conf

Debug 0

GenericExecuteSynth "printf %s \'$DATA\' | /home/xubuntu/.local/bin/piper --length_scale 1 --sentence_silence 0  --model ~/.local/share/piper/voices/$VOICE --output-raw | aplay -r 22050 -f S16_LE -t raw -"

# only use medium quality voices to respect the 22050 rate for aplay in the command above.

GenericCmdDependency "piper"
GenericCmdDependency "aplay"
GenericCmdDependency "printf"
GenericSoundIconFolder "/usr/share/sounds/sound-icons/"

GenericPunctNone ""
GenericPunctSome "--punct=\"()<>[]{}\""
GenericPunctMost "--punct=\"()[]{};:\""
GenericPunctAll "--punct"

#GenericStripPunctChars  ""

GenericLanguage  "en" "en_US" "utf-8"

AddVoice        "en"    "MALE1"         "en_US-hfc_male-medium.onnx"
AddVoice        "en"    "FEMALE1"       "en_US-hfc_female-medium.onnx"

DefaultVoice    "en_US-hfc_male-medium.onnx"

#GenericRateForceInteger 1
#GenericRateAdd 1
#GenericRateMultiply 100

Restart speech-dispatcher with speech-dispatcher restart.

Terminate and restart chrome, killall -9 chrome.

Open DevTools, test in console

var voices = speechSynthesis.getVoices().filter(({name}) => name.includes("piper"));
var u = new SpeechSynthesisUtterance();
u.voice = voices[0];
u.text = "Test, test, test. Test to the point it breaks.";
speechSynthesis.speak(u);

console.log(JSON.stringify(voices.map(({default:_default, lang, localService, name, voiceURI}) => ({_default, lang, localService, name, voiceURI})), null, 2));

VM924:6 [
  {
    "_default": false,
    "lang": "en",
    "localService": true,
    "name": "en_US-hfc_female-medium.onnx piper",
    "voiceURI": "en_US-hfc_female-medium.onnx piper"
  },
  {
    "_default": false,
    "lang": "en",
    "localService": true,
    "name": "en_US-hfc_male-medium.onnx piper",
    "voiceURI": "en_US-hfc_male-medium.onnx piper"
  }
]