drcheck 1.1.0

Dynamic Range Analyzer - Fight the Loudness War

DR Check - Dynamic Range Analyzer

DR Check is a modern, fast, and accurate tool for measuring the dynamic range (DR) of audio files using the DR14 algorithm. Built from the ground up in Python, it provides professional-grade analysis with beautiful output formats.

Fight the Loudness War by analyzing and comparing the dynamic range of your music collection!

✨ Features

• 🎯 Accurate DR14 Calculation - Validated against professional tools (foobar2000 DR Meter)
• 📁 Multiple Audio Formats - FLAC, WAV, MP3, M4A, OGG, AIFF, and more
• 🎨 Beautiful HTML Reports - Modern, responsive design with automatic album art extraction
• 📊 Multiple Output Formats - Text tables, BBCode (for forums), CSV, and HTML
• 🔍 Batch Processing - Analyze entire albums or recursively scan music libraries
• ⚡ Parallel Processing - Multi-core support for high-speed library analysis
• 🎵 Metadata Support - Extracts artist, album, sample rate, bit depth, and format info
• ⚡ Fast & Modern - Clean Python 3.10+ codebase with type hints
• 🧪 Well Tested - Comprehensive test suite with 81+ passing tests

📸 Screenshots

Text Output

DR Check - Dynamic Range Analyzer v1.1.0
log date: 2026-01-10 10:40:05

--------------------------------------------------------------------------------
Analyzed: Willie Nelson / Red Headed Stranger
--------------------------------------------------------------------------------

DR     Peak           RMS            Duration  Track
--------------------------------------------------------------------------------
DR11   -1.28 dBFS     -16.66 dBFS    2:25      01. Time Of The Preacher
DR11   -1.60 dBFS     -17.18 dBFS    1:32      02. I Couldn't Believe It Was True
DR11   -0.16 dBFS     -16.93 dBFS    1:13      03. Time Of The Preacher Theme
DR14   -3.38 dBFS     -20.01 dBFS    1:35      04. Medley- Blue Rock Montana - Red Headed Stranger
DR11   -2.00 dBFS     -16.81 dBFS    2:21      05. Blue Eyes Crying In The Rain
DR12   -1.10 dBFS     -16.32 dBFS    3:59      06. Red Headed Stranger
DR12   -4.35 dBFS     -19.44 dBFS    0:26      07. Time Of The Preacher Theme
DR11   -1.91 dBFS     -19.03 dBFS    1:48      08. Just As I Am
DR12   -2.55 dBFS     -18.47 dBFS    0:53      09. Denver
DR12   -6.14 dBFS     -21.08 dBFS    0:47      10. O'er The Waves
DR11   -3.83 dBFS     -17.57 dBFS    1:56      11. Down Yonder
DR12   -2.12 dBFS     -18.11 dBFS    5:23      12. Can I Sleep In Your Arms
DR11   -1.60 dBFS     -15.38 dBFS    2:52      13. Remember Me (When The Candle Lights Are Gleaming)
DR12   -0.65 dBFS     -15.98 dBFS    4:22      14. Hands On The Wheel
DR11   -3.52 dBFS     -18.10 dBFS    2:15      15. Bandera
--------------------------------------------------------------------------------

Number of tracks:  15
Official DR value: DR12

Samplerate:        96000 Hz
Channels:          2
Bits per sample:   24
Bitrate:           4608 kbps
Codec:             FLAC
================================================================================

HTML Output

Beautiful, modern reports with:

• Album artwork (automatically extracted)
• Color-coded DR values (green/orange/red)
• Responsive design for desktop and mobile
• Complete technical information
• Professional styling

🚀 Quick Start

Installation

PyPi

# pip
pip install drcheck

# pipx
pipx install drcheck

Local git checkout w/ uv

# Clone the repository
git clone https://github.com/nixternal/drcheck.git
cd drcheck

# Install with uv (recommended)
uv pip install -e .

# Or with pip
pip install -e .

Basic Usage

# Analyze a single file
drcheck analyze song.flac

# Analyze an entire album
drcheck analyze /path/to/album/

# Recursive scan of music library
drcheck analyze -r /path/to/music/library/

# Save results to file
drcheck analyze album/ --save

# Generate HTML report
drcheck analyze album/ --save --format html

📖 Usage Guide

Commands

analyze

Analyze audio files and calculate DR14 values.

drcheck analyze [OPTIONS] PATHS...

Options:

• -r, --recursive - Recursively scan subdirectories
• --show-channels - Show per-channel DR values for stereo files
• --save - Save results to file
• -o, --output DIR - Output directory (default: source directory)
• --format FORMAT - Output format: text, bbcode, csv, html (default: text)
• --filename NAME - Output filename (default: dr.txt, auto-adjusts extension)
• -j, --workers N - Number of parallel workers (auto-selects based on job size)

Examples:

# Single file analysis
drcheck analyze mysong.flac

# Album analysis with text output
drcheck analyze album_folder/

# Save as HTML report
drcheck analyze album/ --save --format html

# Recursive scan, save as CSV
drcheck analyze -r music_library/ --save --format csv -o ~/reports/

# Show per-channel DR values
drcheck analyze stereo_file.flac --show-channels

# Multiple paths
drcheck analyze album1/ album2/ single.flac

# Parallel processing with 4 workers
drcheck analyze -r music_library/ -j 4

scan

Preview files that would be analyzed without processing them.

drcheck scan [OPTIONS] PATH

Options:

• -r, --recursive - Recursively scan subdirectories

Example:

drcheck scan -r /music/library/

formats

List all supported audio formats.

drcheck formats

Output Formats

Text (default)

Clean ASCII tables suitable for terminals and text files.

drcheck analyze album/ --save --format text

HTML

Beautiful, modern reports with album art and color-coded DR values.

drcheck analyze album/ --save --format html

Features:

• Automatic album art extraction (from files or folder images)
• Responsive design (mobile-friendly)
• Color-coded DR values
• Complete technical information
• Self-contained (single HTML file)

BBCode

Formatted for posting on audio forums.

drcheck analyze album/ --save --format bbcode

CSV

Spreadsheet-compatible format for data analysis.

drcheck analyze album/ --save --format csv

Or pipe directly:

drcheck analyze album/ --format csv > results.csv

🎵 Supported Audio Formats

Lossless (via libsndfile):

• FLAC (.flac)
• WAV (.wav)
• AIFF (.aiff, .aif, .aifc)
• OGG Vorbis (.ogg, .oga)
• Opus (.opus)

Lossy (requires pydub + ffmpeg):

• MP3 (.mp3)
• M4A/AAC (.m4a, .mp4, .aac)
• WMA (.wma)

To enable MP3/M4A support:

# Install pydub
uv pip install pydub

# Install ffmpeg (system package)
# Ubuntu/Debian:
sudo apt install ffmpeg

# macOS:
brew install ffmpeg

# Arch Linux:
sudo pacman -S ffmpeg

🔬 Understanding DR Values

The DR (Dynamic Range) scale measures the difference between the loudest and average loudness of an audio track:

DR Value	Quality	Description
DR14+	🟢 Excellent	Wide dynamic range, natural sound
DR8-13	🟡 Good	Moderate compression, still enjoyable
DR0-7	🔴 Poor	Heavily compressed, "loudness war" victim

Note: Higher DR doesn't always mean "better" - it depends on the genre and artistic intent. Classical and jazz typically have DR14+, while modern pop/rock often ranges from DR6-10.

🧪 Development

Running Tests

# Install dev dependencies
uv pip install pytest pytest-cov

# Run all tests
pytest tests/ -v

# Run with coverage report
pytest tests/ --cov=drcheck --cov-report=html

# Run specific test file
pytest tests/test_analysis.py -v

Project Structure

drcheck/
├── drcheck/              # Main package
│   ├── __init__.py
│   ├── analysis.py       # Core DR14 calculation
│   ├── audio.py          # Audio file reading
│   ├── cli.py            # Command-line interface
│   ├── formatters.py     # Output formatting
│   └── parallel.py       # Parallel processing
├── tests/                # Test suite
│   ├── test_analysis.py
│   ├── test_audio.py
│   ├── test_formatters.py
│   └── test_parallel.py
├── README.md
└── pyproject.toml

Code Quality

• ✅ Full type hints (pyright compliant)
• ✅ Modern Python 3.10+ features
• ✅ Comprehensive test coverage (81+ tests)
• ✅ Clean, documented code
• ✅ Follows Python best practices

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Guidelines

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Make your changes
4. Add tests for new functionality
5. Ensure all tests pass (pytest tests/)
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

📝 License

This project is licensed under the GNU General Public License v3.0 - see the LICENSE file for details.

🙏 Acknowledgments

• Based on the DR14 algorithm by the Pleasurize Music Foundation
• Inspired by the original dr14_t.meter by Simone Riva
• Validated against the foobar2000 DR Meter plugin

🔗 Related Resources

• Dynamic Range Database - Browse DR values for albums
• Pleasurize Music Foundation - Learn about the DR measurement
• Loudness War - Wikipedia article on the loudness war

📧 Contact

• Issues: GitHub Issues
• Discussions: GitHub Discussions

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Made with ❤️ for music lovers who care about sound quality