Chatterbox TTS API

This project includes an optional React-based web UI. Use Docker Compose profiles to easily opt in or out of the frontend:

With Docker Compose Profiles

# API only (default behavior)
docker compose -f docker/docker-compose.yml up -d

# API + Frontend + Web UI (with --profile frontend)
docker compose -f docker/docker-compose.yml --profile frontend up -d

# Or use the convenient helper script for fullstack:
python start.py fullstack

# Same pattern works with all deployment variants:
docker compose -f docker/docker-compose.gpu.yml --profile frontend up -d    # GPU + Frontend
docker compose -f docker/docker-compose.uv.yml --profile frontend up -d     # uv + Frontend
docker compose -f docker/docker-compose.cpu.yml --profile frontend up -d    # CPU + Frontend

Local Development

For local development, you can run the API and frontend separately:

# Start the API first (follow earlier instructions)
# Then run the frontend:
cd frontend && npm install && npm run dev

Click the link provided from Vite to access the web UI.

Build for Production

Build the frontend for production deployment:

cd frontend && npm install && npm run build

You can then access it directly from your local file system at /dist/index.html.

Port Configuration

• API Only: Accessible at http://localhost:4123 (direct API access)
• With Frontend: Web UI at http://localhost:4321, API requests routed via proxy

The frontend uses a reverse proxy to route requests, so when running with --profile frontend, the web interface will be available at http://localhost:4321 while the API runs behind the proxy.

Default Voice (JSON)

import requests

response = requests.post(
    "http://localhost:4123/v1/audio/speech",
    json={
        "input": "Hello world!",
        "exaggeration": 0.8
    }
)

with open("output.wav", "wb") as f:
    f.write(response.content)

Upload Voice with Language (Multilingual)

import requests

# Upload a multilingual voice
with open("german_voice.wav", "rb") as voice_file:
    response = requests.post(
        "http://localhost:4123/voices",
        data={
            "voice_name": "german_speaker",
            "language": "de"
        },
        files={
            "voice_file": ("german_voice.wav", voice_file, "audio/wav")
        }
    )

print(f"Upload status: {response.status_code}")

# Generate German speech
response = requests.post(
    "http://localhost:4123/v1/audio/speech",
    json={
        "input": "Guten Tag! Wie geht es Ihnen?",
        "voice": "german_speaker",
        "exaggeration": 0.8
    }
)

with open("german_output.wav", "wb") as f:
    f.write(response.content)

Upload Endpoint (Default Voice)

import requests

response = requests.post(
    "http://localhost:4123/v1/audio/speech/upload",
    data={
        "input": "Hello world!",
        "exaggeration": 0.8
    }
)

with open("output.wav", "wb") as f:
    f.write(response.content)

Custom Voice Upload

import requests

with open("my_voice.mp3", "rb") as voice_file:
    response = requests.post(
        "http://localhost:4123/v1/audio/speech/upload",
        data={
            "input": "Hello with my custom voice!",
            "exaggeration": 0.8,
            "temperature": 1.0
        },
        files={
            "voice_file": ("my_voice.mp3", voice_file, "audio/mpeg")
        }
    )

with open("custom_output.wav", "wb") as f:
    f.write(response.content)

Basic Streaming Example

import requests

# Stream audio generation in real-time
response = requests.post(
    "http://localhost:4123/v1/audio/speech/stream",
    json={
        "input": "This will stream as it's generated!",
        "exaggeration": 0.8
    },
    stream=True  # Enable streaming mode
)

with open("streaming_output.wav", "wb") as f:
    for chunk in response.iter_content(chunk_size=8192):
        if chunk:
            f.write(chunk)
            print(f"Received chunk: {len(chunk)} bytes")

SSE Streaming Example (OpenAI Compatible)

import requests
import json
import base64

# Stream audio using Server-Side Events format
response = requests.post(
    "http://localhost:4123/v1/audio/speech",
    json={
        "input": "This streams as Server-Side Events!",
        "stream_format": "sse",
        "exaggeration": 0.8
    },
    stream=True,
    headers={'Accept': 'text/event-stream'}
)

audio_chunks = []

for line in response.iter_lines(decode_unicode=True):
    if line.startswith('data: '):
        event_data = line[6:]  # Remove 'data: ' prefix

        try:
            event = json.loads(event_data)

            if event.get('type') == 'speech.audio.delta':
                # Decode base64 audio chunk
                audio_data = base64.b64decode(event['audio'])
                audio_chunks.append(audio_data)
                print(f"Received audio chunk: {len(audio_data)} bytes")

            elif event.get('type') == 'speech.audio.done':
                usage = event.get('usage', {})
                print(f"Complete! Tokens: {usage.get('total_tokens', 0)}")
                break
        except:
            continue

print(f"Received {len(audio_chunks)} audio chunks")

📚 Complete Streaming Examples & Documentation →

Including real-time playback, progress monitoring, custom voice uploads, and advanced integration patterns.

Replace the default voice sample:

# Replace the default voice sample
cp your-voice.mp3 voice-sample.mp3

# Or set a custom path
echo "VOICE_SAMPLE_PATH=/path/to/your/voice.mp3" >> .env

For best results:

• Use 10-30 seconds of clear speech
• Avoid background noise
• Prefer WAV or high-quality MP3

Development

docker compose -f docker/docker-compose.yml up

Production

# Create production environment
cp .env.example.docker .env
nano .env  # Set production values

# Deploy
docker compose -f docker/docker-compose.yml up -d

With GPU Support

# Use GPU-enabled compose file
# Ensure NVIDIA Container Toolkit is installed
docker compose -f docker/docker-compose.gpu.yml up -d

API Endpoints

Parameters Reference

Speech Generation Parameters

Exaggeration (0.25-2.0)

• 0.3-0.4: Professional, neutral
• 0.5: Default balanced
• 0.7-0.8: More expressive
• 1.0+: Very dramatic

CFG Weight (0.0-1.0)

• 0.2-0.3: Faster speech
• 0.5: Default pace
• 0.7-0.8: Slower, deliberate

Temperature (0.05-5.0)

• 0.4-0.6: More consistent
• 0.8: Default balance
• 1.0+: More creative/random

Stream Format

• audio: Raw audio streaming (default)
• sse: Server-Side Events with base64-encoded audio chunks (OpenAI compatible)

The API includes advanced memory management to prevent memory leaks and optimize performance:

Memory Management Features

• Automatic Cleanup: Periodic garbage collection and tensor cleanup
• CUDA Memory Management: Automatic GPU cache clearing
• Memory Monitoring: Real-time memory usage tracking
• Manual Controls: API endpoints for manual cleanup operations

Memory Configuration

Memory Monitoring Endpoints

# Get memory status
curl http://localhost:4123/memory

# Trigger manual cleanup
curl "http://localhost:4123/memory?cleanup=true&force_cuda_clear=true"

# Reset memory tracking (with confirmation)
curl -X POST "http://localhost:4123/memory/reset?confirm=true"

Real-time Status Tracking

Monitor TTS processing in real-time:

# Check current processing status
curl "http://localhost:4123/v1/status/progress"

# Get detailed status with memory and stats
curl "http://localhost:4123/v1/status?include_memory=true&include_stats=true"

# View processing statistics
curl "http://localhost:4123/v1/status/statistics"

# Check request history
curl "http://localhost:4123/v1/status/history?limit=5"

# Get comprehensive API information
curl "http://localhost:4123/info"

Status Response Example:

{
  "is_processing": true,
  "status": "generating_audio",
  "current_step": "Generating audio for chunk 2/4",
  "current_chunk": 2,
  "total_chunks": 4,
  "progress_percentage": 50.0,
  "duration_seconds": 2.5,
  "text_preview": "Your text being processed..."
}

See Status API Documentation for complete details.

Memory Testing

Run the memory management test suite:

# Test memory patterns and cleanup
python tests/test_memory.py  # or: uv run tests/test_memory.py

# Monitor memory during testing
watch -n 1 'curl -s http://localhost:4123/memory | jq .memory_info'

Memory Optimization Tips

For High-Volume Production:

MEMORY_CLEANUP_INTERVAL=3
CUDA_CACHE_CLEAR_INTERVAL=2
ENABLE_MEMORY_MONITORING=false  # Reduce logging overhead
MAX_CHUNK_LENGTH=200             # Smaller chunks for less memory usage

For Development/Debugging:

MEMORY_CLEANUP_INTERVAL=1
CUDA_CACHE_CLEAR_INTERVAL=1
ENABLE_MEMORY_MONITORING=true

Memory Leak Prevention:

• Tensors are automatically moved to CPU before deletion
• Gradient tracking is disabled during inference
• Audio chunks are cleaned up after concatenation
• CUDA cache is periodically cleared
• Python garbage collection is triggered regularly

Run the test script to verify the API functionality:

python tests/test_api.py

The test script will:

• Test health check endpoint
• Test models endpoint
• Test API documentation endpoints (new!)
• Generate speech for various text lengths
• Test custom parameter validation
• Test error handling with validation
• Save generated audio files as test_output_*.wav

FastAPI Benefits:

• Async support: Better concurrent request handling
• Faster serialization: JSON responses ~25% faster than Flask
• Type validation: Pydantic models prevent invalid requests
• Auto documentation: No manual API doc maintenance

Hardware Recommendations:

• CPU: Works but slower, reduce chunk size for better memory usage
• GPU: Recommended for production, significantly faster
• Memory: 4GB minimum, 8GB+ recommended
• Concurrency: Async support allows better multi-request handling

Common Issues

CUDA/CPU Compatibility Error

RuntimeError: Attempting to deserialize object on a CUDA device but torch.cuda.is_available() is False

This happens because chatterbox-tts models require PyTorch with CUDA support, even when running on CPU. Solutions:

# Option 1: Use default setup (now includes CUDA-enabled PyTorch)
docker compose -f docker/docker-compose.yml up -d

# Option 2: Use explicit CUDA setup (traditional)
docker compose -f docker/docker-compose.gpu.yml up -d

# Option 3: Use uv + GPU setup (recommended for GPU users)
docker compose -f docker/docker-compose.uv.gpu.yml up -d

# Option 4: Use CPU-only setup (may have compatibility issues)
docker compose -f docker/docker-compose.cpu.yml up -d

# Option 5: Clear model cache and retry with CUDA-enabled setup
docker volume rm chatterbox-tts-api_chatterbox-models
docker compose -f docker/docker-compose.yml up -d --build

# Option 6: Try uv for better dependency resolution
uv sync
uv run uvicorn app.main:app --host 0.0.0.0 --port 4123

For local development, install PyTorch with CUDA support:

# With pip
pip uninstall torch torchvision torchaudio
pip install torch==2.6.0 torchvision==0.21.0 torchaudio==2.6.0 --index-url https://download.pytorch.org/whl/cu124
pip install git+https://github.com/travisvn/chatterbox-multilingual.git@exp

# With uv (handles this automatically)
uv sync

Windows Users, using pip & having issues:

pip install torch torchvision torchaudio --index-url https://download.pytorch.org/whl/cu121 --force-reinstall
pip install --force-reinstall typing_extensions

Port conflicts

# Change port
echo "PORT=4124" >> .env

GPU not detected

# Force CPU mode
echo "DEVICE=cpu" >> .env

Out of memory

# Reduce chunk size
echo "MAX_CHUNK_LENGTH=200" >> .env

Model download fails

# Clear cache and retry
rm -rf models/
uvicorn app.main:app --host 0.0.0.0 --port 4123  # or: uv run main.py

FastAPI startup issues

# Check if uvicorn is installed
uvicorn --version

# Run with verbose logging
uvicorn app.main:app --host 0.0.0.0 --port 4123 --log-level debug

# Alternative startup method
python main.py

Project Structure

This project follows a clean, modular architecture for maintainability:

app/                     # FastAPI backend application
├── __init__.py           # Main package
├── config.py            # Configuration management
├── main.py              # FastAPI application
├── models/              # Pydantic models
│   ├── requests.py      # Request models
│   └── responses.py     # Response models
├── core/                # Core functionality
│   ├── memory.py        # Memory management
│   ├── text_processing.py # Text processing utilities
│   └── tts_model.py     # TTS model management
└── api/                 # API endpoints
    ├── router.py        # Main router
    └── endpoints/       # Individual endpoint modules
        ├── speech.py    # TTS endpoint
        ├── health.py    # Health check
        ├── models.py    # Model listing
        ├── memory.py    # Memory management
        └── config.py    # Configuration

frontend/                # React frontend application
├── src/
├── Dockerfile
├── nginx.conf          # Integrated proxy configuration
└── package.json

docker/                  # Docker files consolidated
├── Dockerfile
├── Dockerfile.uv       # uv-optimized image
├── Dockerfile.gpu      # GPU-enabled image
├── Dockerfile.cpu      # CPU-only image
├── Dockerfile.uv.gpu   # uv + GPU image
├── docker-compose.yml  # Standard deployment
├── docker-compose.uv.yml # uv deployment
├── docker-compose.gpu.yml # GPU deployment
├── docker-compose.uv.gpu.yml # uv + GPU deployment
└── docker-compose.cpu.yml # CPU-only deployment

tests/                   # Test suite
├── test_api.py         # API tests
└── test_memory.py      # Memory tests

main.py                  # Main entry point
start.py                 # Development helper script

Quick Start Scripts

# Development mode with auto-reload
python start.py dev

# Production mode
python start.py prod

# Full Stack mode with UI (using Docker)
python start.py fullstack

# Run tests
python start.py test

# View project structure
python start.py info

Local Development

# Install in development mode (pip)
pip install -e .

# Or with uv (basic development tools)
uv sync

# Or with test dependencies (for contributors)
uv sync --group test

# Start with auto-reload (FastAPI development)
uvicorn app.main:app --host 0.0.0.0 --port 4123 --reload

# Or use the main script
python main.py

# Or use the development helper
python start.py dev

Testing

# Run API tests
python tests/test_api.py  # or: uv run tests/test_api.py

# Run memory tests
python tests/test_memory.py

# Test specific endpoint
curl http://localhost:4123/health

# Check API documentation
curl http://localhost:4123/openapi.json

FastAPI Development Features

• Auto-reload: Use --reload flag for development
• Interactive docs: Visit /docs for live API testing
• Type hints: Full IDE support with Pydantic models
• Validation: Automatic request/response validation
• Modular structure: Easy to extend and maintain

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Ensure FastAPI docs are updated
6. Submit a pull request