bpm4b 9.0.0

MP3 to M4B Audiobook Converter - Convert MP3 files to M4B format with chapter support

MP3 to M4B Audiobook Converter (bpm4b)

A Flask-based web application for converting MP3 files to M4B audiobook format with chapter support.

Install and run with: pip install bpm4b then bpm4b

BPM4B - Professional AI Audiobook Suite (v9.0.0)

A professional multimedia processing suite for converting MP3 to M4B, M4B to MP3, and generating AI Audiobooks from documents with high-fidelity TTS and automatic chapter support.

Installation

pip install bpm4b

For local development:

git clone https://github.com/jdjchelp-jpg/bpm4b.git
cd bpm4b
pip install -e .

Features

🎯 Document to Audiobook (AI Gen)

• Convert PDF, DOCX, TXT, and EPUB to high-quality audiobooks.
• Powered by Kokoro-82M High-Fidelity local TTS (no Cloud costs).
• Automatic chapter detection and timing.

📁 Unified Media Conversion

• MP3 to M4B: Create chapterized audiobooks for Apple Books/Audible.
• M4B to MP3: Convert audiobooks to standard high-quality MP3 (128k+).
• Integrated FFmpeg processing for lossy/lossless conversion.

⏱ Automatic Chapter Builder

• Interactive timestamp generator.
• Support for HH:MM:SS and Seconds format.
• Batch import/export of chapter metadata.

🚀 Premium Web Interface

• Modern Glassmorphism UI.
• Real-time progress monitoring.
• Drag-and-drop workflow.

Usage

Web Interface

bpm4b web

Then navigate to http://localhost:5000.

CLI Commands

# Convert MP3 to M4B
bpm4b convert input.mp3 output.m4b

# Convert M4B to MP3
bpm4b convert archive.m4b audio.mp3

# Generate AI Audiobook from PDF
bpm4b audiobook book.pdf book.m4b --voice af_heart

Requirements

• Python 3.8+
• FFmpeg (Installed and in PATH)

API Endpoints

POST /api/mp3-to-m4b

Converts an MP3 file to M4B with optional chapters.

Form Data:

• mp3_file: The MP3 file to convert
• chapters (optional): JSON array of chapter objects. start_time accepts seconds (number) or MM:SS format (string):

[
  {"title": "Chapter 1", "start_time": 0},
  {"title": "Chapter 2", "start_time": "6:30"},
  {"title": "Chapter 3", "start_time": 3600}
]

Response: Returns an M4B file as a download.

Project Structure

.
├── bpm4b/              # Main package directory
│   ├── __init__.py    # Package initialization
│   ├── app.py         # Flask application (for local development)
│   ├── cli.py         # Command-line interface entry point
│   ├── core.py        # Shared core functions
│   ├── api/
│   │   ├── __init__.py
│   │   └── index.py   # Vercel serverless function
│   └── templates/
│       └── index.html # Frontend interface
├── setup.py           # Package installation configuration
├── vercel.json        # Vercel configuration
├── requirements.txt   # Python dependencies
├── uploads/           # Temporary uploaded files (created automatically)
├── outputs/           # Generated files (created automatically)
└── README.md          # This file

Notes

• Maximum file size for uploads: 100MB
• Temporary files are cleaned up automatically
• M4B output files can be large (typically 0.96-2GB per hour of audio depending on bitrate)
• The default audio bitrate is 64kbps AAC, which provides good quality for speech

License

MIT