Changelog : V13.2 : Make Python path portable using user home (~/.venvs/audio312) V13.1 : improve thirds m/M detection 🔥 V13 – BeatGrid-Aware Chord Detection (DJ Clean Engine)
🎯 Major Update
This version introduces VirtualDJ BeatGrid integration (fixed & variable BPM) to significantly improve chord timing accuracy and musical relevance.
⸻
🧠 New Features
🎧 BeatGrid Integration (VirtualDJ XML)
- Supports both:
- ✔ Fixed BPM (Bpm + Phase)
- ✔ Variable BPM (fluid) (BeatGrid=...)
- Automatically extracts beat positions from VirtualDJ database
- Falls back to librosa beat detection if unavailable
👉 Result: chords are now aligned with actual DJ beat structure
⸻
⚡ Improved Timing Accuracy
- Chords are snapped to:
- nearest beat (with tolerance)
- real musical grid instead of estimated rhythm
- Much better coherence for DJ mixing & cueing V12 - Stable release
AI-powered chord detection and injection tool for VirtualDJ database.xml.
This tool analyzes your audio files (AIFF, WAV, FLAC, etc.), applies fine pitch detection and correction to A=440 Hz, and writes chords as POI markers directly into VirtualDJ. It also creates an automatic fine pitch POI so tracks can be played closer to A=440 Hz, making them easier to use with external instruments such as synths, VSTs, or piano.
Make sure to have this kind of Python path:
/Users/YOUR_USERNAME/.venvs/audio312/bin/python
- Fast batch chord detection
- Fine pitch detection & correction (to A=440 Hz)
- Writes chords directly into VirtualDJ database
- Automatic database backup
- Supports large libraries (thousands of tracks)
- Optimized for macOS (Apple Silicon)
Tested with:
- VirtualDJ 2026 > BUILD 9295 (2026-04-19) (New Fluid Database.xml synthax)
This AppleScript expects Python to be installed at:
property pythonBin : "/Users/" & (short user name of (system info)) & "/.venvs/audio312/bin/python"
So you must create the Python environment exactly here:
~/.venvs/audio312
Copy and paste:
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"Then (Apple Silicon Macs):
eval "$(/opt/homebrew/bin/brew shellenv)"brew install pythonCheck installation:
python3 --versionmkdir -p ~/.venvs
python3 -m venv ~/.venvs/audio312source ~/.venvs/audio312/bin/activatepython -m pip install --upgrade pippip install numpy scipy librosa soundfile~/.venvs/audio312/bin/python -c "import numpy, scipy, librosa, soundfile; print('Python environment OK')"Expected output:
Python environment OK
Do NOT move or rename this folder:
~/.venvs/audio312
The AppleScript depends on this exact path.
You can reinstall everything:
rm -rf ~/.venvs/audio312
python3 -m venv ~/.venvs/audio312
source ~/.venvs/audio312/bin/activate
pip install numpy scipy librosa soundfileor use this file :
xattr -d com.apple.quarantine install-python-requirements.sh 2>/dev/null || true
chmod +x install-python-requirements.sh
./install-python-requirements.shFFmpeg is recommended for decoding compressed audio and video formats (MP3, AAC, MP4, MOV, WEBM, MKV).
On macOS, basic formats may work without FFmpeg (CoreAudio), but installing FFmpeg ensures full compatibility.
Install with Homebrew: brew install ffmpeg
This script needs access to your files and VirtualDJ database.
You must grant Full Disk Access to the application running the AppleScript.
-
Open System Settings
-
Go to Privacy & Security
-
Click Full Disk Access
-
Add:
- Script Editor (if you run the script from it)
- OR the compiled AppleScript app
- OR Terminal (if running via Terminal)
-
Restart the application
- Do NOT open VirtualDJ during analysis
- Always backup your
database.xmlbefore running the script - Use this tool at your own risk (advanced users only)
Make sure to have this kind of Python path:
/Users/YOUR_USERNAME/.venvs/audio312/bin/python
Applescript auto detect YOUR_USERNAME : property pythonBin : "/Users/" & (short user name of (system info)) & "/.venvs/audio312/bin/python"
- Double-click:
CHORD-DETECTION-VIRTUALDJ.scpt
- The AppleScript file and the Python (.py) file must be located in the same folder for the script to run correctly
-
Select your
database.xml -
Choose analysis mode:
- Full folder
- Single file
- Filter by first letter
- Let the analysis run in Terminal
- Tracks should already be analyzed by VirtualDJ (BPM, grid, etc.) using VirtualDJ 2026 (build 9295 or newer), as this version introduces the updated fluid BeatGrid format required for accurate chord placement.
- The script automatically closes VirtualDJ before starting
- Do NOT reopen VirtualDJ during analysis
- This may corrupt or overwrite your database
/Volumes/YourDrive/VirtualDJ/database.xml
👉 Auto-detected by the script if available
/Users/YOUR_USERNAME/Library/Application Support/VirtualDJ/database.xml
- Always select the database matching your audio files location
- Using the wrong database will result in:
- Missing chords
- Wrong library being modified
If you get errors like:
Operation not permitted Permission denied
Enable Full Disk Access:
System Settings → Privacy & Security → Full Disk Access
Add:
- Terminal
- Script Editor (or the app used to run the script)
This tool directly modifies your VirtualDJ database.xml.
👉 You MUST manually backup your database before using this tool.
Example:
Copy database.xml → database_backup.xml
- This tool is intended for advanced users and developers only
- Incorrect usage may:
- Corrupt your VirtualDJ database
- Cause data loss
- Affect your music library
By using this tool, you agree that:
- You are fully responsible for any changes made
- The author is not responsible for any damage or data loss
- This tool is not affiliated with VirtualDJ or its developers
✔ Always backup your database manually
✔ Do not run VirtualDJ during analysis
✔ Use only if you understand the process
- AIFF ✔ (best)
- WAV ✔
- FLAC ✔
- ALAC
⚠️ (slower analyse) - .m4a .mp3 .aac
⚠️ (slower analyse) - video files (.mov .mp4 .mkv...) (slower analyse)
- macOS (Apple Silicon)
- Python 3.12
- librosa 0.10+
MIT License (recommended)