ai-agent

libKeyFinder: Identify Musical Keys in Your Audio Quickly

Name: libKeyFinder: Identify Musical Keys in Your Audio Quickly
Author: ibsh

Use libKeyFinder to automatically detect the musical key of any digital audio file, helping developers and audio‑focused startups add key analysis to their applications.

From the repo · “Musical key detection for digital audio, GPL v3”

279 stars59 forksC++Guide quality 8/10 · reviewed Oct 10Updated 11/16/2020100% free · open source

What it does

LibKeyFinder detects the musical key of digital audio files, allowing for automatic organization and analysis of music libraries.

When to use it

•When building a music streaming service that needs to suggest songs in the same key as the current playlist
•When creating a music information retrieval system that requires key detection for music recommendation
•When developing a DJ software that needs to analyze and mix songs based on their musical key

Ready-to-paste prompt

./libKeyFinder -i path/to/audio/file.mp3 -o path/to/output/file.txt -t 0.5 -m 1

Heads up: LibKeyFinder requires the FFTW library to be installed and configured properly, which can be a challenge on some platforms, especially when using a version of FFTW that is not compatible with the version expected by libKeyFinder

Saves to your device

Use with Claude

New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

✅ Light setup

Installs with a command or two; your AI agent can do it for you.

Try it instantly — no install

Claude Code

mkdir -p ~/.claude/skills/libkeyfinder && curl -fsSL https://workflowstacks.com/api/skills/libkeyfinder/claude-skill -o ~/.claude/skills/libkeyfinder/SKILL.md

Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)

claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

How libKeyFinder: Identify Musical Keys in Your Audio Quickly works

Codeflow

Free to inspect

LibKeyFinder: Identify Musical Keys in Your Audio Quickly is a small C++ project (~2.1k lines across 32 code files, plus 21 test files). Setup is light: small project — see the README for how to run it. Last commit 72 months ago, GPL-3.0 license, has a test suite.

Size

Small codebase

~2.1k lines · 32 code files · 18 min skim

Setup

Light setup

Small project — see the README for how to run it.

Runs on

C++

No API keys detected

C++ 98%QMake 1%CMake 1%

Where to start reading

1
README.md
Start here — what it does and how to install it

What's in each folder

cmake/Folder1 files

tests/Tests — proof it works23 files

.github/CI / automation (GitHub Actions)1 files

READMEHas testsThin docsCI checksGPL-3.0 licenseLast update 72 mo ago

Use with Claude

New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

✅ Light setup

Installs with a command or two; your AI agent can do it for you.

Try it instantly — no install

Claude Code

mkdir -p ~/.claude/skills/libkeyfinder && curl -fsSL https://workflowstacks.com/api/skills/libkeyfinder/claude-skill -o ~/.claude/skills/libkeyfinder/SKILL.md

Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)

claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

Quick Actions

Details

Creator

ibsh

Language

C++