livekit-plugins-resemble 1.5.0rc1

LiveKit Agents Plugin for Resemble AI

Resemble plugin for LiveKit Agents

Support for voice synthesis with the Resemble AI API, using both their REST API and WebSocket streaming interface.

See https://docs.livekit.io/agents/integrations/tts/resemble/ for more information.

Installation

pip install livekit-plugins-resemble

Pre-requisites

You'll need an API key from Resemble AI. It can be set as an environment variable: RESEMBLE_API_KEY

Additionally, you'll need the voice UUID from your Resemble AI account.

Examples

Recommended

import asyncio
from livekit.plugins.resemble import TTS

async def run_tts_example():
    # Use TTS with async context manager for automatic resource cleanup
    async with TTS(
        api_key="your_api_key",  # or set RESEMBLE_API_KEY environment variable
        voice_uuid="your_voice_uuid",
        # Optional parameters
        sample_rate=44100,  # Sample rate in Hz (default: 44100)
        precision="PCM_16",  # Audio precision (PCM_32, PCM_24, PCM_16, MULAW)
        output_format="wav",  # Output format (wav or mp3)
    ) as tts:
        # One-off synthesis (uses REST API)
        audio_stream = tts.synthesize("Hello, world!")
        
        # Process chunks as they arrive
        async for chunk in audio_stream:
            # Audio data is in the 'frame.data' attribute of SynthesizedAudio objects
            audio_data = chunk.frame.data
            print(f"Received chunk: {len(audio_data)} bytes")
        
        # Alternative: collect all audio at once into a single AudioFrame
        audio_stream = tts.synthesize("Another example sentence.")
        audio_frame = await audio_stream.collect()
        print(f"Collected complete audio: {len(audio_frame.data)} bytes")
        
        # Real-time streaming synthesis (uses WebSocket API)
        # Only available for Business plan users in Resemble AI
        stream = tts.stream()
        await stream.synthesize_text("Hello, world!")
        


# Run the example
asyncio.run(run_tts_example())

Alternative: Manual Resource Management

If you prefer to manage resources manually, make sure to properly clean up:

import asyncio
from livekit.plugins.resemble import TTS

async def run_tts_example():
    # Initialize TTS with your credentials
    tts = TTS(
        api_key="your_api_key", 
        voice_uuid="your_voice_uuid",
    )

    try:
        # TTS operations
        audio_stream = tts.synthesize("Hello, world!")
        async for chunk in audio_stream:
            # Access audio data correctly
            process_audio(chunk.frame.data)
    finally:
        # Always clean up resources when done
        await tts.aclose()

# Run the example
asyncio.run(run_tts_example())

Resource Management

When using this plugin outside of the LiveKit agent framework, it's important to properly manage the TTS instance lifecycle:

1. Preferred method: Use the async context manager pattern (async with TTS(...) as tts:)
2. If managing manually, always call await tts.aclose() in a finally block
3. If you prefer to provide your own HTTP session, you can pass it using the http_session parameter:

import aiohttp

async def with_custom_session():
    async with aiohttp.ClientSession() as session:
        async with TTS(
            api_key="your_api_key",
            voice_uuid="your_voice_uuid",
            http_session=session
        ) as tts:
            # Use TTS...
            # No need to manually close anything - context managers handle it all

Implementation Details

This plugin uses two different approaches to generate speech:

1. One-off Synthesis - Uses Resemble's REST API for simple text-to-speech conversion
2. Streaming Synthesis - Uses Resemble's WebSocket API for real-time streaming synthesis

The WebSocket streaming API is only available for Resemble AI Business plan users.