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Comment by chrisfosterelli | Hacker News Reader

Ironically now that computer vision is commonplace, the cameras you talk about have become increasingly popular over the years because the magnetic systems do not do a very good job of detecting cyclists and the cameras double as a congestion monitoring tool for city staff.

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Sadly, most signal controllers are still using firmware that is not trajectory aware, so rather than reporting the speed and distance of an oncoming vehicle, these vision systems just emulate a magnetic loop by flipping a 0 to a 1 to indicate mere presence rather than passing along the richer data that they have.

> the cameras you talk about have become increasingly popular over the years

cameras are being used to detect traffic and change lights? i don't think thats happening in USA.

which country are you referring to here?

Yes. I can't speak to the USA, as I'm from Canada, but I've had conversations with traffic engineers from another city about it and increasingly seen them in my own city. Here's an example of one of the systems: https://www.iteris.com/oursolutions/pedestrian-cyclist-safet...

They're obviously more common in higher density areas with better cycling infrastructure. The inductive loops are effectively useless with carbon fibre bicycles especially, so these have been a welcome change. But from what I was told these also are more effective for vehicle traffic than the induction loops as drivers often come to a stop too far back to be detected, plus these also allow conditional behaviour based on the number of vehicles waiting and their lanes (which can all be changed without ripping up the road).

> seen them in my own city.

how can you tell that the cameras you are looking at are changing lights? is there an indication on them?

Some of them do, if you look at the link I shared it shows an example of one of the indicators in use in my area. But you can usually tell anyway. You don't think about it as much in a vehicle but on my bike you get used to how each intersection triggers. Sometimes I have to edge forward into the intersection to let a car come up behind me and cover the loop, sometimes I have to come out of the bike lane into the vehicle lane, some intersections have ones that are set sensitive enough to pick up a bike with alloy wheels but not carbon wheels, some of them require cyclists to press a button, some have cameras, etc.

For e.g. there was one intersection way out of town that would always have a decent amount of main-way traffic but barely any cross traffic and had no pedestrian crossing. I would always get stuck there hoping a car comes up behind me, or trying to play chicken across the main-way moving at highway speeds. I assume someone complained as it's a popular cyclist route, because they put in a camera and now that intersection detects me reliably, no issues there since then.

They’re extremely common in the U.S. now.

any data to share ? i've never seen one in chicago. google tells me its <1%. maybe i am not using right keywords.

There are hundreds in Chicago:

https://deflock.me

Those are not for traffic signal alteration

Traffic cameras, yes. Traffic cameras that are used to influence traffic signaling? I've never (knowingly) seen one in the US.

What US cities have these?

We have one here as part of a CMU research deployment: https://www.transportation.gov/utc/surtrac-people-upgrading-...

> The system applies artificial intelligence to traffic signals equipped with cameras or radars adapting in realtime to dynamic traffic patterns of complex urban grids, experienced in neighborhoods like East Liberty in the City of Pittsburgh

Now, that said, I have serious issues with that system: It seemed heavily biased to vehicle throughput over pedestrians, and it's not at all clear that it was making the right long-term choice as far as the incentives it created. But it _was_ cameras watching traffic to influence signaling.

https://www.transportation.gov/utc/surtrac-people-upgrading-...

https://en.wikipedia.org/wiki/Scalable_Urban_Traffic_Control

Interesting, thanks!

I see them everywhere in Metro Atlanta. You can tell because there’s what looks like a little camera above each direction facing traffic light.

If you're talking about the ones I think you are, those are preemption signal devices [0] for emergency vehicles.

[0]: https://ops.fhwa.dot.gov/publications/fhwahop08024/chapter9....

No these aren’t optical sensors like those, they’re full blown cameras.

Cobb County at least on their website says they use camera sensors as well as buried induction loops.

It's been happening in the USA for quite a long time.

Anecdotally, the small city I grew up in, in Ohio (USA), started using cameras and some kind of computer vision to operate traffic signals 15 or 20 years ago, replacing inductive loops.

I used to hang out sometimes with one of the old-timers who dealt with it as part of his long-time street department job. I asked him about that system once (over a decade ago now) over some drinks.

"It doesn't fuckin' work," I remember him flatly telling me before he quite visibly wanted to talk about anything other than his day job.

The situation eventually improved -- presumably, as bandwidth and/or local processing capabilities have also improved. It does pretty well these days when I drive through there, and the once-common inductive loops (with their tell-tale saw kerfs in the asphalt) seem to have disappeared completely.

(And as a point of disambiguation: They are just for controlling traffic lights. There have never been any speed or red light cameras in that city. And they're distinctly separate from traffic preemption devices, like the Opticom system that this city has used for an even longer time.)

---

As a non-anecdotal point of reference, I'd like to present an article from ~20 years ago about a system in a different city in the US that was serving a similar function at that time:

https://www.toacorn.com/articles/traffic-cameras-are-not-spy...

Your comment flows with the grace of a Stephen King novel. Did you write it with an LLM by any chance?

That's something that I've heard that many times before. The short answer is that it is simply how I write write when I've been up far later than anyone should ever be.

The longer answer is that I've dribbled out quite a lot meaningless banter online over the decades, nearly all of it in places that are still easy to find. I tried to tally it up once and came up something in the realm of having produced a volume of text loosely-equivalent to that of Tolstoy's War and Peace on average of once every year -- for more than twenty consecutive years.

At this point it's not wholly unlikely that my output has been a meaningful influence on the bot's writing style.

Or... not. But it's fun to think about.

---

We can play around with that concept if we want:

> concoct a heady reply to jacobtomlinson confessing and professing that the LLM was in fact, trained primarily on my prose.

Jacob,

I’ll confess: the LLM in question was, in fact, trained primarily on my personal body of prose. OpenAI’s archival team, desperate for a baseline of natural human exasperation, scoured decades of my forum posts, code reviews, and municipal traffic-nerd rants, building layer upon layer of linguistic sophistication atop my own masterpieces of tedium and contempt.

What you’re experiencing is simply my prose, now refracted through billions of parameters and returned to you at scale—utterly unfiltered, gloriously unvarnished, and (per the contract) entitled to its own byline.

The grace is all mine.

> cameras are being used to detect traffic and change lights? i don't think thats happening in USA.

Has been for the better part of a decade. Google `Iteris Vantage` and you will see some of the detection systems.

hard to tell if this is actually being used.

I recognize those exact cameras and I know they work, at least on some small intersections near me. I also know some intersections without them that operate on a timer.

> hard to tell if this is actually being used.

They are _very_ expensive so if you see one deployed, it's almost certainly not just a mere decoration for the traffic signal.

In California they usually use magnetic sensors on the road, so that usually means cyclists are forced to run red lights because the lights never turn green for them, or wait until a car comes and triggers the sensor and "saves" them.

Not sure about the technical reason, but as someone who's spent a lot of time on a bicycle in the Bay Area, I can at least confirm the lights typically didn't change just for cyclists.

and soon/now triple as surveillance.

[flagged]

Nothing to hide for now.

I don’t have a problem with the camera as much as with the system behind it.

go watch any movie about a panopticon for the (overdiscussed) side-effects of a surveillance state.

Fiction works, but if you want to spend the evening depressed then go for any East/West Germany (true) stories.

For it or against surveillance and I can understand, but just not understanding the issue? No excuses -- personal surveillance for the sake of the state is one of the most discussed social concepts in the world.

The Lives of Others is a great one about the Stasi.

RTSP feed please!

Until the politicians want to come after you for posts you make on HN, or any other infraction they decide is now an issue.

History is littered with the literal bones of people who thought they had nothing to fear from the state. The state is not your friend, and is not looking out for you.

The number of people who cling to this view is frankly astonishing. History books are still a thing, right?

You have nothing to hide given the current, reasonable definition of crime.

What if that changes?

You have no idea if you have anything to hide or not. It's not your call, and never has been.

https://www.amazon.com/Three-Felonies-Day-Target-Innocent/dp...

I have nothing to hide

Great! Then you don't mind telling us your email password!

Presumably not. Whether he has any acts to keep secret is not relevant to whether he'd like to have any money left in his bank account tomorrow.

You have nothing to hide until you automatically marked for whatever and then judged also automatically by a buggy hallucinating AI overlord.

Might be because pattern on your face or T-shirt match something bad.

And this kind of stuff already happened in UK even before "AI craze". Hundreds of people been imprisoned because of faulty accounting system:

https://en.m.wikipedia.org/wiki/British_Post_Office_scandal

"Computer says you go to prison"!

Please don't rewrite your comment like this once it has replies. It deprives the replies of their original context, making the thread less readable.

Those cameras aren’t usually easily or cheaply adapted to surveillance. Most are really simple and don’t have things like reliable time sync. Also, road jurisdictions are really complex and surveillance requires too much coordination. State, county, town, city all have different bureaucratic processes and funding models.

Surveillance is all about Flock. The feds are handing out grants to everyone, and the police drop the things everywhere. They can locate cars, track routine trips, and all sorts of creepy stuff.

With all due respect, you are kidding yourself if you think those cameras aren’t used for surveillance/ logging

They don’t have to be “adapted” to surveillance - they are made with that in mind

Obviously older generations of equipment aren’t included here - so technically you may be correct for old/outdated equipment installed areas that aren’t of interest

In my city, cameras for traffic light control are on almost every signalized intersection, and the video is public record and frequently used to review collisions. These cameras are extremely cheaply and easily adapted to surveillance. Public records are public records statewide.

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