OVOS Bidirectional Translation Plugin

This package holds two OVOS plugins: a UtteranceTransformer and a DialogTransformer. Together they let OVOS understand and answer in any language, even one the installed skills do not support directly.

This plugin is still in alpha.

Install

pip install ovos-bidirectional-translation-plugin

Language support in OVOS

This section is a refresher on how OVOS handles language.

• A default language is set in mycroft.conf. This is the OVOS primary language. All skills, TTS plugins, and STT plugins must support it.
• Extra languages can also be set in mycroft.conf. STT and TTS plugins in use must support these languages too. If an installed skill does not support one of them, OVOS ignores that skill for that language. Support can also be partial, per intent.
• Skills register intents for each supported language. Together these intents define the languages OVOS can speak.
• Each utterance carries an assigned language, through the session (message.context). OVOS picks this language from, in order of preference:
  • the default language, if nothing else is set
  • the wake word used
  • the language detected in speech (functional plugins for this exist, work is ongoing)
  • the language of a recognized user (not yet implemented)
  • the language set by the client application, for example a HiveMind satellite

{
  // Primary Language
  // Code is a BCP-47 identifier (https://tools.ietf.org/html/bcp47), lowercased
  "lang": "en-us",

  // Secondary languages will also have their resource files loaded into memory
  // but intents will only be considered if that lang is tagged with the utterance at STT step
  "secondary_langs": []
}

How it works

The ovos-utterance-translation-plugin plugin can detect the language of an utterance. When "verify_lang": true is set, it compares the detected language against the session language. This handles cases such as a chat platform where a user can write in any language and the session language may be wrong.

When "ignore_invalid_langs": true is set, the plugin ignores a detected language that is not one of the configured native languages, to guard against false detections. Otherwise, it fixes the session language to the detected one.

Language tags are compared by tag distance, the same rule the rest of OVOS applies. A regional variant counts as one of the native languages, so ar-SA is native when the system supports ar, and pt-BR is native when the system supports pt-PT. A macrolanguage member such as arz is a different language and is translated.

If the session language is not one of the native languages, the plugin translates the utterance to the primary language, so OVOS can understand it.

The native languages are the primary language plus the secondary languages. Set "translate_secondary_langs": true to keep only the primary language native, so the plugin also translates the secondary languages before OVOS handles them.

When "bidirectional": true is set, the ovos-dialog-translation-plugin plugin then translates OVOS dialogs back to the original session language. Otherwise OVOS answers in its primary language, even if the user spoke in a different one.

Prerequisites

This plugin needs a language detection plugin and a language translation plugin configured beforehand.

In ovos-docker, install this plugin in both ovos-core and ovos-audio, together with the translation plugins.

Recommended plugins:

• ovos-translate-plugin-nllb (local)
• ovos-translate-server-plugin (remote, public server list)

{
  "language": {
    "detection_module": "ovos-lang-detect-ngram-lm",
    "translation_module": "ovos-translate-plugin-nllb",
    "ovos-translate-plugin-nllb": {
      "model": "nllb-200_600M_int8"
    }
  }
}

Configuration

{
  "utterance_transformers": {
    "ovos-utterance-translation-plugin": {
      "bidirectional": true,
      "verify_lang": false,
      "ignore_invalid_langs": true,
      "translate_secondary_langs": false
    }
  },
  "dialog_transformers": {
    "ovos-dialog-translation-plugin": {}
  }
}

Related projects

• OpenVoiceOS/ovos-translate-plugin-nllb — local translation plugin
• OpenVoiceOS/ovos-translate-server-plugin — remote translation plugin, backed by a public server list
• OpenVoiceOS/ovos-google-translate-plugin — translation plugin backed by Google Translate

License

Apache-2.0. See LICENSE.