epub2audio 0.1.0

Convert EPUB ebooks to OGG audiobooks with chapter markers

EPUB to Audiobook Converter

A command-line tool and library that converts EPUB ebooks to OGG audiobooks with chapter markers, using local text-to-speech processing with [Kokoro].

Features

• Converts EPUB 3.0 files to OGG audiobooks
• Local text-to-speech processing using Kokoro
• Support for 9 languages with multiple voices:
  • 🇺🇸 American English (11F, 9M voices)
  • 🇬🇧 British English (4F, 4M voices)
  • 🇯🇵 Japanese (4F, 1M voices)
  • 🇨🇳 Mandarin Chinese (4F, 4M voices)
  • 🇪🇸 Spanish (1F, 2M voices)
  • 🇫🇷 French (1F voice)
  • 🇮🇳 Hindi (2F, 2M voices)
  • 🇮🇹 Italian (1F, 1M voices)
  • 🇧🇷 Brazilian Portuguese (1F, 2M voices)
• Chapter markers in output files
• Configurable voice selection and speech rate
• Progress reporting with optional quiet mode
• Metadata preservation from EPUB to audio file

Requirements

• Python 3.10 or higher
• Dependencies listed in pyproject.toml

Installation

1. Clone this repository:

git clone https://github.com/clayrosenthal/epub2audio.git
cd epub2audio

2. Install using mise (recommended):

mise install

Or manually with a virtual environment:

python -m venv .venv
source .venv/bin/activate 
pip install -e .

Usage

Basic Usage

Convert an EPUB file to an audiobook with default settings:

epub2audio input.epub

The audiobook will be saved as Book_Title.ogg, but can be set with --output.

Voice Selection

The tool supports multiple voices across different languages. Here are some notable voices:

American English

• af_bella (Female, Grade A-) - High quality with extended training
• af_heart (Female, Grade A) - Best overall quality
• af_nicole (Female, Grade B-) - Good quality with extended training
• am_fenrir (Male, Grade C+) - Best male voice option

British English

• bf_emma (Female, Grade B-) - Best British female voice
• bm_fable (Male, Grade C) - Best British male voice

Other Languages

• ff_siwis (French Female, Grade B-)
• jf_alpha (Japanese Female, Grade C+)
• if_sara (Italian Female, Grade C)
• hf_alpha (Hindi Female, Grade C)

To use a specific voice:

epub2audio input.epub --voice af_bella

Advanced Options

epub2audio input.epub \
  --output output.ogg \
  --voice af_bella \
  --speech-rate 1.0 \
  --quiet

Command Line Options

• input.epub: Path to input EPUB file
• --output-dir, -o: Directory for output audiobook files (default: ./audiobooks)
• --voice, -v: Name of the voice to use (default: af_heart)
• --speech-rate, -r: Speech rate multiplier (default: 1.0)
• --bitrate, -b: Output audio bitrate (default: 192k)
• --quiet, -q: Suppress progress reporting
• --verbose, -v: Output more verbose logs

Voice Quality Grades

Voices are graded based on quality and training data:

• A: Exceptional quality, extensive training
• B: Good quality, suitable for most uses
• C: Average quality, may have minor issues
• D: Basic quality, may have noticeable issues
• F: Limited quality, recommended only if necessary

Modifiers (+/-) indicate slight variations within each grade.

Development

Project Structure

src/
├── __init__.py
├── epub_processor.py      # EPUB parsing and text extraction
├── audio_converter.py     # TTS conversion using Kokoro
├── audio_handler.py       # OGG creation, chapter markers, metadata
├── cli.py                # Command line interface
├── voices.py             # Voice definitions and management
├── helpers.py            # Utility functions
└── config.py             # Configuration settings

Running Tests

Using mise:

# Run all tests
mise run test

# Run integration tests
mise run test-integration

# Run with coverage
mise run test-coverage

Or manually:

# Run all tests
pytest

# Run integration tests
pytest --run-integration

# Run with coverage
pytest --cov=src tests/

Code Quality

The project uses:

• Ruff for formatting and linting
• MyPy for type checking
• Pytest for testing

To format and lint code:

mise run format  # Format code
mise run lint    # Check code
mise run fix     # Auto-fix issues

Error Handling

Critical Errors (Exit with error code)

1. Invalid/corrupted EPUB file
2. Invalid voice model selection
3. File system errors (read/write permissions)
4. Insufficient disk space

Non-Critical Errors (Warning and continue)

1. Non-text elements in EPUB
2. Unsupported metadata fields
3. Minor formatting issues

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Make your changes
4. Run tests (mise run test)
5. Format code (mise run format)
6. Commit your changes (git commit -m 'Add amazing feature')
7. Push to the branch (git push origin feature/amazing-feature)
8. Open a Pull Request

Development Guidelines

1. Follow Google Python style guide
2. Add tests for new features
3. Update documentation as needed
4. Keep commits focused and atomic

License

AGPL-3.0-or-later - See LICENSE file for details

Acknowledgments

• Kokoro for text-to-speech processing
• ebooklib for EPUB handling
• mutagen for audio metadata
• Voice training data contributors (see individual voice attributions)