OpenAI

The OpenAIVoice class in Mastra provides text-to-speech and speech-to-text capabilities using OpenAI’s models.

Usage Example

import { OpenAIVoice } from '@mastra/voice-openai';
 
// Initialize with default configuration using environment variables
const voice = new OpenAIVoice();
 
// Or initialize with specific configuration
const voiceWithConfig = new OpenAIVoice({
  speechModel: {
    name: 'tts-1-hd',
    apiKey: 'your-openai-api-key'
  },
  listeningModel: {
    name: 'whisper-1',
    apiKey: 'your-openai-api-key'
  },
  speaker: 'alloy'  // Default voice
});
 
// Convert text to speech
const audioStream = await voice.speak('Hello, how can I help you?', {
  speaker: 'nova',  // Override default voice
  speed: 1.2  // Adjust speech speed
});
 
// Convert speech to text
const text = await voice.listen(audioStream, {
  filetype: 'mp3'
});

Configuration

Constructor Options

speechModel?:

OpenAIConfig
= { name: 'tts-1' }
Configuration for text-to-speech synthesis.

listeningModel?:

OpenAIConfig
= { name: 'whisper-1' }
Configuration for speech-to-text recognition.

speaker?:

OpenAIVoiceId
= 'alloy'
Default voice ID for speech synthesis.

OpenAIConfig

name?:

'tts-1' | 'tts-1-hd' | 'whisper-1'
Model name. Use 'tts-1-hd' for higher quality audio.

apiKey?:

string
OpenAI API key. Falls back to OPENAI_API_KEY environment variable.

Methods

speak()

Converts text to speech using OpenAI’s text-to-speech models.

input:

string | NodeJS.ReadableStream
Text or text stream to convert to speech.

options.speaker?:

OpenAIVoiceId
= Constructor's speaker value
Voice ID to use for speech synthesis.

options.speed?:

number
= 1.0
Speech speed multiplier.

Returns: Promise<NodeJS.ReadableStream>

listen()

Transcribes audio using OpenAI’s Whisper model.

audioStream:

NodeJS.ReadableStream
Audio stream to transcribe.

options.filetype?:

string
= 'mp3'
Audio format of the input stream.

Returns: Promise<string>

getSpeakers()

Returns an array of available voice options, where each node contains:

voiceId:

string
Unique identifier for the voice

Notes

  • API keys can be provided via constructor options or the OPENAI_API_KEY environment variable
  • The tts-1-hd model provides higher quality audio but may have slower processing times
  • Speech recognition supports multiple audio formats including mp3, wav, and webm