Tool
unfiteredtruth.cc
Civil rights webapp
Role
research, audio, prototyp, lead, innovation
01
Problem
In the news
In 2021, reports started appearing in various places: US police officers began playing copyrighted material from The Beatles and Co. on their phones when activists were filming them. The obvious goal of the officers was to prevent the civil rights activists from uploading footage of their behavior to social media. Platforms like Instagram, Facebook, and YouTube hinder the upload or distribution of videos when their filters detect known material in the audio track.
02
Prototype
Let audio tracks disappear.
I found a way to hide the audio track from the platforms' copyright filters. A curve in the infrasonic range changes the acoustic fingerprint of the audio track. Since the 20-Hertz range is not perceptible to humans, the sound remains unchanged to our ears. Only the filters get confused. With a simple prototype that included the key functions, I tested the assumptions and improved the filter within a few days.
03
Webapp
Open and secure.
The web app enables easy conversion on mobile and desktop devices: load a video snippet in the browser, convert it with a click, check the result, and save it back to the device. Since the material can be sensitive, the web app follows the highest security standards: the conversion happens on the device, and no video or audio data is sent over the internet. For maximum transparency, the source code is available on GitHub under a permissive open-source license.
04
Background
Filter against filter.
Behind the scenes of social media platforms, algorithms break down the sound into smaller segments and look for characteristics. Fast Fourier Transforms, Mel-spectrograms, tempograms, or chromagrams represent different features of the same waveform. This highly visual process is called fingerprinting. And like real fingerprints, these are matched with a database. But instead of criminals, the database contains fingerprints of countless music tracks. This explains the success of Unfilteredtruth: the loud but inaudible infrasounds distort the swirls and lines of the fingerprints, making comparison impossible.