Description

Open Voice OS microphone plugin for python-sounddevice library.

python-sounddevice uses PortAudio as audio library to interact with audio components.

PortAudio is a free, cross-platform, open-source, audio I/O library. It lets you write simple audio programs in 'C' or C++ that will compile and run on many platforms including Windows, Macintosh OS X, and Unix (OSS/ALSA). It is intended to promote the exchange of audio software between developers on different platforms. Many applications use PortAudio for Audio I/O.

This plugin is ideal for macOS (Intel and Apple Silicon) and also works on Linux. On macOS it uses CoreAudio stream settings tuned for clear wake-word and STT capture.

Install

pip install ovos-microphone-plugin-sounddevice

Configuration

In order to inform the listener which plugin to use (default is set to ovos-microphone-plugin-alsa), the mycroft.conf configuration file should be updated.

{
  "listener": {
    "microphone": {
      "module": "ovos-microphone-plugin-sounddevice",
      "ovos-microphone-plugin-sounddevice": {}
    }
  }
}

macOS Recommended (Clear Capture)

{
  "listener": {
    "microphone": {
      "module": "ovos-microphone-plugin-sounddevice",
      "ovos-microphone-plugin-sounddevice": {
        "device": "Built-in Microphone",
        "latency": "low",
        "multiplier": 1.0,
        "blocksize": 1024,
        "queue_maxsize": 8,
        "use_coreaudio_settings": true,
        "coreaudio_conversion_quality": "max",
        "coreaudio_change_device_parameters": false,
        "coreaudio_fail_if_conversion_required": false,
        "auto_sample_rate_fallback": true,
        "auto_channel_fallback": true,
        "auto_latency_fallback": true
      }
    }
  }
}

Device Selection

• Exact name: "device": "Built-in Microphone"
• Substring match: "device": "Built-in"
• Regex match: "device": "regex:^MacBook.*Microphone"
• Numeric index: "device": 0
• Default input device: omit device or set "device": "default"

Notes

• Keep multiplier near 1.0 for the cleanest signal.
• Increase multiplier only if the microphone is too quiet.
• If clipping/distortion appears, reduce multiplier below 1.0.
• If 16000 Hz input is not supported by hardware, the plugin can open the device at native sample rate and resample to 16000 Hz for OVOS.
• blocksize controls callback cadence; lower values usually improve wakeword responsiveness.