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Show HN: Glasses to detect smart-glasses that have cameras

(github.com)
509 points nullpxl | 10 comments | 28 Nov 25 05:52 UTC | HN request time: 0.615s | source | bottom

Hi! Recently smart-glasses with cameras like the Meta Ray-bans seem to be getting more popular. As does some people's desire to remove/cover up the recording indicator LED. I wanted to see if there's a way to detect when people are recording with these types of glasses, so a little bit ago I started working this project. I've hit a little bit of a wall though so I'm very much open to ideas!

I've written a bunch more on the link (+photos are there), but essentially this uses 2 fingerprinting approaches: - retro-reflectivity of the camera sensor by looking at IR reflections. mixed results here. - wireless traffic (primarily BLE, also looking into BTC and wifi)

For the latter, I'm currently just using an ESP32, and I can consistently detect when the Meta Raybans are 1) pairing, 2) first powered on, 3) (less consistently) when they're taken out of the charging case. When they do detect something, it plays a little jingle next to your ear.

Ideally I want to be able to detect them when they're in use, and not just at boot. I've come across the nRF52840, which seems like it can follow directed BLE traffic beyond the initial broadcast, but from my understanding it would still need to catch the first CONNECT_REQ event regardless. On the bluetooth classic side of things, all the hardware looks really expensive! Any ideas are appreciated. Thanks!

1. wowamit ◴[28 Nov 25 07:57 UTC] No.46076523[source]▶
A much-needed project. Making yourself invisible to such privacy-invasive devices will be the need of the day. Of the two approaches you mentioned, blocking/jamming the specific wireless traffic would be pretty interesting, if possible.
replies(3): >>46076805 #>>46077799 #>>46080233 #
2. aDyslecticCrow ◴[28 Nov 25 08:42 UTC] No.46076805[source]▶
> blocking/jamming the specific wireless traffic would be pretty interesting, if possible.

And probably highly illegal.

replies(4): >>46076940 #>>46077538 #>>46078135 #>>46078710 #
3. wowamit ◴[28 Nov 25 09:05 UTC] No.46076940[source]▶
Yeah, true. Implementing this would be tricky.
replies(1): >>46077212 #
4. aDyslecticCrow ◴[28 Nov 25 09:52 UTC] No.46077212{3}[source]▶
Implementing it is trivial. you can just overlook the radio from openWRT and drown out every 2.4-2.5 gHz device in a 100M radius.

Doing it targeted is more difficult since it does frequency hopping, but you could probably reverse the frequency hopping algorithm to target specifically Bluetooth and force high packet loss.

This is still illegal for radio jamming reasons, and also patent infringement since a misbehaving Bluetooth device has not gotten permission to use Bluetooth patents held by SIG.

5. A4ET8a8uTh0_v2 ◴[28 Nov 25 11:02 UTC] No.46077538[source]▶
At the end of the day, legality is what society settles as an acceptable way of running itself when all the stakeholders reluctantly agree or at least don't protest too much. Right now the 'costs' are sufficiently low that no one cares. As with most things, I suspect that there is a threshold ( though likely much higher than I have previously anticipated ) at which normal person would be unwilling to go as if anything changed.
replies(1): >>46081819 #
6. unsupp0rted ◴[28 Nov 25 11:47 UTC] No.46077799[source]▶
I'll feel much safer when I'm visible only to every single ATM camera, traffic camera, random smartphone camera and doorbell camera, but not to people's glasses.
7. jeroenhd ◴[28 Nov 25 12:41 UTC] No.46078135[source]▶
Deauth attacks weer common in the Google Glasses days. Nobody got arrested as far as I can remember.
8. ◴[28 Nov 25 16:44 UTC] No.46080233[source]▶
9. aDyslecticCrow ◴[28 Nov 25 19:17 UTC] No.46081819{3}[source]▶
Nobody cares? Here (sweden) its illegal to possess outside of military use. The US seems to give fines between 20-200 thousand $ for its usage and potential imprisonment for its sale. Even overboosting wifi routers for better range gets people in trouble.

It's among the most illegal things you could easily do with basic electronics equipment.

why? Part of it is historical; it used to be complicated, so being in possession of one got you in trouble with the anti terrorism squad.

These days; it's because it can block emergency services, police and military radio, and burglary alarms.

They may be lenient for a nerd playing with a router but the law its not on your side when push comes to shove.

https://legalclarity.org/are-signal-jammers-illegal-in-the-u...

replies(1): >>46083044 #
10. iamnothere ◴[28 Nov 25 21:45 UTC] No.46083044{4}[source]▶
This is overstating the case. In the US you can buy such devices (usually from Aliexpress but Amazon has devices capable of some jamming/deauth). They are illegal to use for intentional jamming of other people’s equipment. However, unless you go around jamming important safety equipment or making local hams angry then nothing will happen. The FCC has its hands full and can’t even seem to address persistent issues on the ham bands until they get really bad.