chord-analyzer

What This Skill Does

The Chord Analyzer skill is a powerful music information retrieval tool designed to bridge the gap between raw audio files and musical theory. By utilizing advanced digital signal processing libraries such as librosa, this skill processes audio files to extract high-level harmonic and rhythmic data. It systematically performs feature extraction, mapping the frequency content into pitch class profiles (chroma features) to determine the tonal center of the music. The output provides users with a comprehensive snapshot of a song's musical identity, including the detected key signature, estimated tempo in BPM, a chronological list of chord progressions, and a breakdown of chord usage statistics.

Installation

To begin using the Chord Analyzer, ensure you have Python 3 installed on your system. First, navigate to your workspace directory and install the required dependencies using the following command:

pip3 install librosa numpy scipy scikit-learn soundfile

Once installed, you can integrate the chord_analyzer.py script into your workflow. Ensure the audio files you wish to analyze are accessible via a valid system path. For optimal results, keep your input audio files under 5 minutes in duration and ensure they are in a supported format like mp3, wav, flac, or m4a.

Use Cases

This skill is ideal for musicians, songwriters, and music theorists who need quick, automated harmonic insights. Use this tool when you need to identify the foundational chords of a piece of music to learn a song, compose variations, or study song structure. It is particularly helpful for hobbyists looking to understand the key signature of a recording or identifying the tempo for synchronization tasks. It serves as an excellent starting point for musical transcription before moving to more intensive manual analysis.

Example Prompts

1. "Analyze this audio file at /Users/music/song.mp3 and list the chord progression for me."
2. "What is the key signature and tempo of the audio file I just uploaded?"
3. "Extract the harmonic structure and tell me which chords appear most frequently in this track."

Tips & Limitations

While the Chord Analyzer is highly effective for basic triad-based music, it has distinct limitations. It currently struggles with complex, heavily layered, or distorted audio, as these elements can obscure the chroma features. The detection engine is optimized for triads (major, minor, diminished) and does not interpret complex jazz extensions like 7ths, 9ths, or 13ths. Furthermore, song structure detection is limited to basic segmentation rather than high-level verse/chorus identification. For professional-grade transcription or detailed instrument separation, we recommend using dedicated professional software or web-based services. Always ensure your audio files have a clear rhythmic and harmonic profile for the best results.