Wake Word Plugins

All Mycroft Wake Word Plugins need to provide a class derived from the HotWordEngine base class in mycroft.client.speech.hotword_factory

When the __init__() method of the base class is run the config for that module will be loaded and available through self.config. Mycroft's selected language will also be available through self.lang.

For example, the following Mycroft configuration:

{
  "listener": {
    "wake_word": "my wake word",
  },
  "hotwords": {
    "my wake word": {
      "module": "example_wake_word_plugin",
      "custom_attribute": "some value"
    }
  }
}

will load the "my wake word" structure from the "hotwords" section using the "example_wake_word_plugin" . The defined custom_attribute will then be available within my plugin on self.config

found_wake_word()

Each Wake Word plugin must define the found_wake_word() method taking one argument:

• frame_data - this is the audio data that needs to be checked for a wake word. You can process audio here or return a result previously handled in the update() method.

update()

The update() method is optional and takes one argument:

• chunk - live audio chunks allowing for streaming predictions. Results must be returned in the found_wake_word() method.

stop()

The stop() method is optional and takes no arguments. It should be used to perform any actions needed to shut down the hot word engine. This may include things such as unloading data or to shutdown external processes.

Entry point

To make the class detectable as a Wake Word plugin, the package needs to provide an entry point under the mycroft.plugin.wake_word namespace.

setup([...],
      entry_points = {'mycroft.plugin.wake_word': 'example_wake_word_plugin = my_example_ww:myWakeWordEngine'}
      )

Where:

• example_wake_word_plugin is the Wake Word module name for the plugin

• my_example_ww is the Python module; and

• myWakeWordEngine is the class in the module to return