Audio privacy for video platforms
The planes overhead can give away where a video was filmed.
A newly demonstrated technique matches the faint sound of passing aircraft in a recording against public flight-tracking data to work out where it was made. In one public test it got within about 100 meters. Removing metadata doesn't help, because the clue is in the sound itself. Doxblock is building protection that works on videos that are already published.
Talk to usThe problem
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Planes leave a fingerprint
Aircraft engines and propellers give off low, steady tones. As a plane passes, the Doppler effect bends that tone down in pitch. The shape of the bend depends on the plane's speed and how close it came. Most people never notice it under speech or music, but it shows up clearly on a spectrogram, and phones, cameras and doorbells all pick it up.
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Flight paths are public
Most aircraft constantly broadcast their position, altitude and speed (ADS-B). Volunteer networks archive that data, so anyone can look up which planes were where at any moment.
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Match one to the other
A search can predict the pitch curve each real flight would have produced at each point on a map, then compare those predictions with the recording to narrow down where the microphone was. A known recording time, or a couple of flyovers, is enough to make that search practical.
Why common fixes fall short
- Stripping metadata or GPS tags doesn't touch the audio.
- A high-pass filter has to cut into the range of the human voice, and in public tests the curve was still recoverable afterward.
- Talking over it, phone-call compression and ordinary noise reduction have also left it recoverable.
Who is exposed
Streamers broadcasting from home, journalists and their sources, activists, people who have left abusive relationships, and anyone who posts a clip filmed somewhere they would rather keep private.
Where things stand
The technique was first shown publicly in November 2026. For now it is slow and only works in the right conditions: aircraft within earshot, flight-tracking coverage, and enough unedited audio. Independent reimplementations are already appearing, though, and methods like this tend to get faster and easier over time. The videos that are online today will still be online when they do.
Our approach
Doxblock processes the audio track of existing videos so that aircraft signatures can no longer be matched to a location, without audibly changing how they sound. The picture is left untouched. We're building it to these goals:
- Works on what's already published. Designed for back catalogs, not only new uploads.
- Unnoticeable to viewers. Checked with objective audio-quality metrics and blind listening tests.
- Platform scale. Batch processing for large libraries, plus a low-latency path for live streams.
- Tested against a capable attacker. We measure protection against an adversary who knows how our defense works, not only against the published method.
Doxblock is in active development. We're looking for platform partners and early pilot users.
Get in touch
We're talking with video and streaming platforms, creators and researchers. Tell us a little about what you need and we'll get back to you.