juanra/audiobook-forge v2.9.1

v2.9.1 - M4B Merge Feature

on GitHub

🔗 M4B Merge Feature

This release adds the ability to combine multiple M4B files into a single file without re-encoding — directly addressing user feedback about lossless M4B concatenation.

✨ New Features

• Lossless M4B Merge: Combine multiple M4B files using FFmpeg's concat demuxer with -c copy for zero quality loss
• Smart Pattern Detection: Automatically identifies related files by naming patterns:
  • Part patterns: Part 1, Part 2, Pt 1, Pt. 1
  • Disc patterns: Disc 1, Disc1, CD1, CD 1, Disk 1
  • Numeric suffix: Book 01.m4b, Book 02.m4b
• Chapter Preservation: All chapters from source files are merged with correctly adjusted timestamps
• --merge-m4b Flag: Force merge multiple M4B files even when no naming pattern is detected

📖 Usage

# Auto-detect sequential parts and merge
audiobook-forge build --root /path/to/book

# Force merge even without detected pattern
audiobook-forge build --root /path/to/book --merge-m4b

🔧 Technical Changes

• Added BookCase::E for classifying folders with multiple mergeable M4B files
• New M4bMerger module for handling lossless concatenation
• New merge_chapter_lists function for combining chapters with timestamp offsets
• Updated scanner to detect and sort M4B files by part number
• 9 new integration tests for merge functionality

📦 Installation

cargo install audiobook-forge

Full Changelog: v2.9.0...v2.9.1