midiVERTO: A Web Application to Visualize Tonality in Real Time

TL;DR

midiVERTO is a web app that visualizes musical tonality in real time by applying Fourier analysis to MIDI files, making complex music theory concepts accessible to non-experts.

Contribution

It introduces a user-friendly web application that visualizes Fourier coefficients of MIDI files to analyze harmonic properties without requiring advanced math skills.

Findings

Visualizes harmonic functions, triadicity, and diatonicity over time

Bridges mathematical music theory and public understanding

Enables real-time tonality analysis of MIDI compositions

Abstract

This paper presents a web application for visualizing the tonality of a piece of music -- the organization of its chords and scales -- at a high level of abstraction and with coordinated playback. The application applies the discrete Fourier transform to the pitch-class domain of a user-specified segmentation of a MIDI file and visualizes the Fourier coefficients' trajectories. Since the coefficients indicate different musical properties, such as harmonic function, triadicity, and diatonicity, the application isolates aspects of a piece's tonality and shows their development in time. The aim of the application is to bridge a gap between mathematical music theory, musicology, and the general public by making the discrete Fourier transform as applied to the pitch-class domain accessible without requiring advanced mathematical knowledge or programming skills up front.