5 ms·
Be careful with this one. If you see a house/apartment where lights are repeatedly being turned on/off that’s generally considered a signal that they are in dis
by IgorPartola 5y ago
Be careful with this one. If you see a house/apartment where lights are repeatedly being turned on/off that’s generally considered a signal that they are in distress and you might get first responders dispatched to you curtesy of a neighbor who saw this and called 911.
Also I honestly can’t think of a worst way to try to save money, especially after you factor in the power it might take to do the facial recognition. There would be a good chance that you actually lose money unless you are in a hanger full of Na lights.
Edit: 5 bulbs in a room that each consume 10 watts (fairly generous), people blink up to 20k times a day, an average blink is 100 ms. So that’s 2000 seconds of blink time or just about 33 minutes. 33*5*10 is 28 Watt-hours saved per day or about 0.84 kWh per month. At the rate of $0.20 per kWh you just saved $0.16 a month.
But wait you have latency to detect the blink so let’s cut that figure by 15%. And since we don’t know how long a blink will last (some are shorter) you also need to reduce the off time by one standard deviation of a blink so to be safe let’s make the off period after detection last only 60 ms. So now we are at $0.096 per month. And now we also need to run multiple cameras and facial detection which has to run continuously. Unless you can do that under 28*0.6=16.8 Wh per day you are losing money.
- seszett 5y ago> If you see a house/apartment where lights are repeatedly being turned on/off that’s generally considered a signal that they are in distress I would assume that they just have kids.
- robertakarobin 5y ago> they are in distress > they just have kids Is there a difference?
- MattGaiser 5y agoI suspect it is more relevant for a time when you would have been more likely to have known your neighbours.
- ALittleLight 5y agoUnless I had established the blinking light code with my neighbors in advance, how would blinking lights inform me any more if I knew my neighbors or not? Unless they were blinking out S.O.S. it would not occur to me that it might be a sign of distress.
- srmarm 5y agoI think it's intended as a joke / proof of concept!
- IgorPartola 5y agoYeah I get that. But knowing the HN crowd I think it’s worth doing the math and pointing out how playing with this could result in unintended consequences.
- forgotmypw17 5y agoI think the simplest fix for that would be to also track the eyes (and view range) of everyone else within a reasonable distance. My cat could do that in Perl in 5 minutes and 3 lines.
- vokep 5y agoWhere can I get a cat like that?
- forgotmypw17 5y agoYou don't get Perl Cat, Perl Cat gets you
- xwdv 5y agoShould you call 911 if you see a place with lights flash on and off repeatedly?
- voxic11 5y agoMaybe if they are doing it in a SOS pattern.
- jxy 5y agoCool, now you've found a real use for smart home lighting system.
- IgorPartola 5y agoYou know, I was taught this as a kid and the answer was yes. But now I cannot find a reference to this anywhere. It’s possible I am wrong.
- kube-system 5y agoI heard this as a kid too. Thinking back, maybe I was just annoying my mom by playing with the light switch.
- bryanrasmussen 5y ago>Be careful with this one. If you see a house/apartment where lights are repeatedly being turned on/off that’s generally considered a signal that they are in distress because of the supernatural events taking place inside!
- DonHopkins 5y agoMaybe you could generate power by harnessing the wind generated by moving your eyelashes? Mount tiny little nano-windmills on each of them, with accelerometers, so you don't even need to use computer vision. Every time you blink it would generate just enough power to send a signal to your lightbulb.
- twobitshifter 5y agoJust glue a momentary push button under your eyelashes and connect it to a headlamp. No need for all this overengineering.
- Moodles 5y agoIn what situation would you switch the lights on and off constantly to signal you need help? The only situation I can think of is that you're somehow too injured to make noise or move, but you're able to reach the light switch?
- MattGaiser 5y agoThink elderly people who might have a lamp beside them in bed or who are stuck on the floor near a lamp, but wouldn't carry around a cell phone. I haven't heard a lot about it, but anecdotally have heard of it outside of HN.
- IgorPartola 5y agoI have heard of it in the context of domestic violence when a person locks themselves in a room without a phone and is trying to signal to the outside world that they are in trouble.
- Moodles 5y agoRight. In the case they’re locked in a room without their phone and the domestic abuser doesn’t also notice them turning the light on and off, I guess it would be an ok strategy? But again, that seems pretty farfetched. I have heard of cases where they call 911 and “order a pizza” and the operator catches on though.
- 5y ago
- baby 5y agoUh, no
- the_mitsuhiko 5y agoI don’t think this is a thing. When you have kids extended periods of flashing lights are very common.