About: Virtual Choir Maker

Virtual Choir Maker uses math, engineering, and computer algorithms to syncrohonize your tracks, mix them together, draw a gridded video, and send you the result.

You only need to worry about carefully recording your tracks in sync with a reference track. All the track syncronization, audio engineering, and video editing is done by the automated tools. You don’t need extra software, you don’t need video editing skills, you don’t need a monster PC to crunch everything.

Under the hood, many of the audio processing functions are handled by librosa and pydub. Video and audio reading/writing is handled by ffmpeg. Gridded video rendering is done with opencv. The code is written in python. It is open-source, you can go take a look at it, and even run the tools on your own computer. You can find the Virtual Choir Maker source code on github.

About: the Author

Virtual Choir Maker is written by Curtis Olson. Curt has a full time day job a the University of Minnesota, Aerospace Engineering Department, Unmanned Aerial Systems Lab. There he is chief test pilot and contributes to a variety of research and student projects. Curt’s degree is in Computer Science if you were wondering why an aerospace engineering is writing python code to automate virtual choir construction. Oh, and actually quite a few concepts developed or learned at Curt’s day job show up here in this project!

About: the Automated Cloud Tools

As I write this, the cloud system that processes your requests is literally a linux server in Curt’s basement. The system is able to sync your tracks from a google shared folder if you have made the folder visable (read-only with the link.) Your results are shared back with you using Filemail and will be available for 7 days.


There is no way to keep a full list of everyone to thank, but for their invaluable help getting this project rolling, providing ideas, and samples to test with, many many thanks to:

  • Kathleen Hansen - Master Director, San Diego Chorus
  • Clement Cano - Vocal Arts Director, Sacred Heart Schools, Atherton CA