ovos-audio

ovos-audio is the audio daemon for OpenVoiceOS. It handles text-to-speech (TTS) synthesis and sound playback, and it runs as a background service that connects to the OVOS MessageBus.

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Install

pip install ovos-audio[extras]

The extras group installs this package with the default plugins. Without it, you must install and configure TTS modules yourself, as described below.

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Configuration

ovos-audio reads its settings from mycroft.conf.

{

  // Text to Speech parameters
  "tts": {
    "module": "ovos-tts-plugin-server",
    "fallback_module": "ovos-tts-plugin-mimic",
    "ovos-tts-plugin-mimic": {
        "voice": "ap"
    }
  },

  // File locations of sounds to play for system events
  "sounds": {
    "start_listening": "snd/start_listening.wav",
    "end_listening": "snd/end_listening.wav",
    "acknowledge": "snd/acknowledge.mp3",
    "error": "snd/error.mp3"
  },

  // Mechanism used to play WAV audio files
  "play_wav_cmdline": "paplay %1 --stream-name=mycroft-voice",

  // Mechanism used to play MP3 audio files
  "play_mp3_cmdline": "mpg123 %1",

  // Mechanism used to play OGG audio files
  "play_ogg_cmdline": "ogg123 -q %1"
}

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Persona Support

ovos-audio supports dialog-transformer plugins that rewrite generated speech to match a tone or persona. See the technical manual's dialog transformers page for the full transformer chain and priority rules.

For example, ovos-solver-plugin-openai-persona rewrites text before synthesis, based on a persona string. Sample personas:

• "rewrite the text as if you were explaining it to a 5-year-old"
• "rewrite the text as if it was an angry old man speaking"
• "Add more 'dude'ness to it"

Example input and output with the "explain to a 5-year-old" persona:

• Input: "Quantum mechanics is a branch of physics that describes the behavior of particles at the smallest scales."
• Output: "Quantum mechanics is like a special kind of science that helps us understand really tiny things."

To enable the plugin, add this to mycroft.conf:

"dialog_transformers": {
    "ovos-dialog-transformer-openai-plugin": {
        "rewrite_prompt": "rewrite the text as if you were explaining it to a 5-year-old"
    }
}

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Using Legacy AudioService

The legacy audio service handles audio playback through the old Mycroft API. See the implementation in mycroft-core and ovos-bus-client.

By default, OCP delegates to the legacy audio service when needed, so no action is required. If you disable OCP, this API becomes the sole media playback provider.

Note: once ovos-media is released, OCP and this API will be disabled by default and deprecated.

See docs/audio-service.md for the module reference, and the technical manual's OCP audio plugin page for how OCP relates to this subsystem.

{
    "enable_old_audioservice": true,
    "disable_ocp": true,
    "Audio": {
        "default-backend": "vlc",
        "backends": {
          "simple": {
            "type": "ovos_audio_simple",
            "active": true
          },
          "vlc": {
            "type": "ovos_vlc",
            "active": true
          }
        }
    }
  },
}

Legacy backend plugins:

• ovos-vlc-plugin
• ovos-audio-plugin-simple (no HTTPS support)
• ovos-audio-plugin-mpv (recommended default)
• ovos-media-plugin-chromecast
• ovos-media-plugin-spotify

About OCP:

• OCP was developed for mycroft-core under the legacy audio service system.
• OCP is always the default audio plugin, unless "disable_ocp": true is set in the config.
• OCP uses the legacy API internally to delegate playback when the GUI is unavailable, or when configured to do so.
• OCP does not support old Mycroft CommonPlay skills. The "ocp_legacy" pipeline in ovos-core handles that instead.
• ovos-media will fully replace OCP in ovos-audio 1.0.0.

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Related Projects

• ovos-media, the replacement for OCP and the legacy audio service
• ovos-core, the assistant core that starts and manages ovos-audio
• ovos-plugin-manager, plugin discovery for TTS, G2P, and audio backends
• ovos-bus-client, the MessageBus client used to communicate with ovos-audio

See docs/index.md for a full architecture overview.

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License

ovos-audio is licensed under the Apache License 2.0.