Dialog Transformers

Dialog Transformers in OpenVoiceOS (OVOS) are plugins that modify or enhance text responses just before they are sent to the Text-to-Speech (TTS) engine. This allows for dynamic adjustments to the assistant's speech, such as altering tone, simplifying language, or translating content, without requiring changes to individual skills.

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How They Work

1. Intent Handling: After a user's utterance is processed and an intent is matched, the corresponding skill generates a textual response.
2. Transformation Phase: Before this response is vocalized, it passes through any active dialog transformers.
3. TTS Output: The transformed text is then sent to the TTS engine for audio synthesis.

This pipeline ensures that all spoken responses can be uniformly modified according to the desired transformations.

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Configuration

To enable dialog transformers, add them to your mycroft.conf file under the dialog_transformers section:

"dialog_transformers": {
  "plugin_name": {
    // plugin-specific configuration
  }
}

Replace "plugin_name" with the identifier of the desired plugin and provide any necessary configuration parameters.

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Available Dialog Transformer Plugins

OVOS Dialog Normalizer Plugin

• Purpose: Prepares text for TTS by expanding contractions and converting digits to words, ensuring clearer pronunciation.

• Example:

  • Input: "I'm 5 years old."
  • Output: "I am five years old."

• Installation:

pip install ovos-dialog-normalizer-plugin

• Configuration:

"dialog_transformers": {
  "ovos-dialog-normalizer-plugin": {}
}

• Source: GitHub Repository

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OVOS OpenAI Dialog Transformer Plugin

• Purpose: Utilizes OpenAI's API to rewrite responses based on a specified persona or tone.

• Example:

  • Rewrite Prompt: "Explain like I'm five"
  • Input: "Quantum mechanics is a branch of physics that describes the behavior of particles at the smallest scales."
  • Output: "Quantum mechanics helps us understand really tiny things."

• Installation:

pip install ovos-openai-plugin

• Configuration:

"dialog_transformers": {
    "ovos-dialog-transformer-openai-plugin": {
      "rewrite_prompt": "Explain like I'm five"
    }
}

• Source: GitHub Repository

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OVOS Bidirectional Translation Plugin

• Purpose: Translates responses to match the user's language, enabling multilingual interactions.

• Features:

  • Detects the language of the user's input.
  • Works together with a companion utterance transformer plugin
  • Translates the assistant's response back into the user's language.

• Installation:

pip install ovos-bidirectional-translation-plugin

• Configuration:

"dialog_transformers": {
    "ovos-bidirectional-dialog-transformer": {
      "bidirectional": true
    }
}

• Source: GitHub Repository

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Creating Custom Dialog Transformers

To develop your own dialog transformer:

Create a Python Class:

from ovos_plugin_manager.templates.transformers import DialogTransformer

class MyCustomTransformer(DialogTransformer):
   def __init__(self, config=None):
       super().__init__("my-custom-transformer", priority=10, config=config)

   def transform(self, dialog: str, context: dict = None) -> Tuple[str, dict]:
        """
        Optionally transform passed dialog and/or return additional context
        :param dialog: str utterance to mutate before TTS
        :returns: str mutated dialog
        """
       # Modify the dialog as needed
        return modified_dialog, context

Register as a Plugin: In your setup.py, include:

entry_points={
   'ovos.plugin.dialog_transformer': [
       'my-custom-transformer = my_module:MyCustomTransformer'
   ]
}

Install and Configure: After installation, add your transformer to the mycroft.conf:

"dialog_transformers": {
  "my-custom-transformer": {}
}