---
title: Emotopa - Patterns in Pitch Organization
canonical: https://0110.be/posts/Emotopa_-_Patterns_in_Pitch_Organization
markdown_url: https://0110.be/posts/Emotopa_-_Patterns_in_Pitch_Organization.md
id: 499
published_at: '2022-12-10T00:00:00Z'
updated_at: '2022-12-20T14:38:27Z'
author: Joren
tags:
- name: UGent
  markdown_url: https://0110.be/tags/UGent.md
---

# Emotopa - Patterns in Pitch Organization

<div style="float:right; width:22%">
<center>
<a href="https://0110.be/attachment/cors/2022.12.emotopa/">\
<img style="width:80%" src="https://0110.be/files/attachments/499/emotopa_screenshot.png" alt="Screenshot of a browser based pitch organization extraction tool"></a><br>\
<small>Fig: Screenshot of *Emotopa*: a browser based tool to extract pitch organization from audio.</small>

</center>
</div>
A couple of days ago I participated in the [Music Hack Day - India](https://musichackdayindia.github.io/). The event was organized the 10th and 11th of December in Bangaluru, India. During the event a representative of [Smule](https://www.smule.com/) suggested a task to evaluate the performance of karaoke-singers in terms of intonation. The idea was to employ pitch histogram like features to estimate pitch use of singers.

I offered to build a browser based application to extract pitch histograms from audio. At the end of the hack day I presented the [first release of *Emotopa*](https://0110.be/attachment/cors/2022.12.emotopa/) with some limited functionality:

1.  The application is able to decode and use audio from any format or container by using an [audio focused webassambly build of ffmpeg](https://github.com/JorenSix/ffmpeg.audio.wasm).

2.  Next, a pitch detector runs on the audio and returns a list of pitch estimates.

3.  Finally a histogram (technically a kernel density estimate) is constructed using the pitch estimates.

The user can export the pitch histogram, the pitch class histogram and the pitch annotations. These features successfully show the intonation quality of singers but the applications are much broader. Some potential applications have been described in (amongst others) the [Tarsos article](https://0110.be/publications/Tarsos%2C_a_modular_platform_for_precise_pitch_analysis_of_western_and_non-western_music).

The Emotopa name alludes to the [Apotome](https://isartum.net/apotome) browser based app where, starting from a scale you can make music. With Emotopa you do the reverse. Also very much of interest are [Leimma](https://isartum.net/leimma) and the [rationale behind both Apotome and Leimma](https://pitchfork.com/thepitch/decolonizing-electronic-music-starts-with-its-software/)

The source can be verified on the [Emotopa GitHub repository](https://github.com/JorenSix/Emotopa)

<small style="color:#AAA">This contribution was made possible thanks to travel funds by the FWO travel grant K1D2222N and the Ghent University BOF funded project PaPiOM.</small>