Cheap ANPR

Man of Honour
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Nvidia jetson or older TX1 would be better than a Pi. IIRC it can analyse 6 HD streams at once.
I have just found this project:
https://medium.com/@alannewcomer/license-plate-recognition-with-a-jetson-nano-e94c6ff683bc

Definitely seems more up to the task. I’ll explore further.

All of the projects I have seen so far have been for use cases involving static cars. I wonder how a clean image of a moving car at a distance of 10m could be sourced for analysis. I think the only way to find out is to prototype it. Unless anyone else has ideas?
 
Caporegime
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Private lane used by multiple people, some legit, some not, and the legit ones change often... People accessing his property regularly, some legit, some not...

Owner wants to know who is going in and out...

Sounds like an interesting situation ;) Is the owner in an interesting line of work? ;)
 
Soldato
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You say it's already covered by CCTV are they analogue or are they IP cameras.?

If IP then there's no need for a Pi at the location you can just use the Camera feed and run the software on any existing PC
 
Man of Honour
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Update for anyone interested or considering something similar.

This project was put on ice for a while but a trespass and access rights dispute reignited it. When I took a look again, there is a very user friendly and competent solution which was borne from the OpenALPR project, Rekor Scout, although it does require subscription of 8 USD per month.

We have installed a relatively cheap spare HD IP camera covering the lane in question. It is Lorex brand, manufactured by Dahua I think. Going for around £70 used on eBay. Nothing fancy but gives a 4k resolution picture and is IP66 rated. It runs via some external grade CAT5e to a PoE switch in the house. Rekor Scout is currently running on his W10 daily computer and is doing an impressive job of picking up pretty much every plate going by, even on the faster traffic, and in sub-optimal lighting conditions. Accuracy for plates is >95% so far. Even more impressive is that if it doesn't catch a plate, it can detect the profile of the vehicle and give a make and model. This is working with >80% accuracy.

Night performance needs some work but I think this can be improved with a separate IR source closer to the vehicles so the reliance on the camera's IR source is reduced.

The next step is to host the software on a much lower power unit. It does seem to be quite CPU intensive at times, due in most part I think to the sensitive motion detection driving lots of unnecessary image analysis. I'm going to experiment with different settings to see if it can be optimised. Alternatively, a camera with a longer lens would give a narrower field of view which could be better targeted; this will be considered if software optimisation isn't effective.

Overall project cost so far:
Camera - £73
Cable - ~£10
Software subscription - $96 per year.
6 pints - £28.80
TOTAL (1 year) - £195.80

Potential costs:
Camera with a longer focal length - £100-150.
IR light source - £25.
Power hookup for IR light - £20.
Separate machine to host it - ~£200?
 
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Caporegime
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Nice, pretty cool that it could be solved so cheaply thanks to a neat open source solution + off the shelf hardware.

A locked gate isn’t feasible as the faff involved with stopping and getting out to open and close is not tenable. The users of the lane change frequently and administering the dishing out of keys, codes, or fobs would be a pain.

Re: this, obvs an automated gate hooked up to the ANPR system would be very cool but temporarily perhaps trying an unlocked gate/barrier might be worth a shot now you've got a system in place for logging and recording the trespassers.

It could be the case that an unlocked gate or even just a simple barrier or chain deters most random drivers who'd have otherwise just taken a chance down a private road, you'd soon find out via the logging from the ANPR software but also being unlocked and say on a spring or similar means authorised users don't need to faff with a lock but can hop out, push the back, drive past and then unhook it and let it swing back into place behind them.

It would have to be some really determined self-righteous trespassers to carry on using a road with a barrier across it - though I guess if that is part of the problem then this won't necessarily stop them.. albeit the logging would perhaps end up being entirely them.
 
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Man of Honour
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Re: this, obvs an automated gate hooked up to the ANPR system would be very cool but temporarily perhaps trying an unlocked gate/barrier might be worth a shot now you've got a system in place for logging and recording the trespassers.

It is an absolute faff, even left unlocked with a deterrent. We have to do it at work outside the hours the site is open to the public and most people will just leave the gate open after a couple of weeks or so of doing it unless you keep on their case (and I hate doing it myself). We used to have a security company managing it but that turned into a big drama because somehow it is too difficult for the business, landlord and security company to just communicate and get on the same page :s and in the end the security company dropped the contract.
 
Man of Honour
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Obviously there's power at the lane because you're running the ANPR equipment so why couldn't you have just installed a powered barrier with fob/tag entry?

Similar to the ones you see at coastal caravan parks
No mains power at the camera mounting point. It runs on PoE.

If you can find a powered barrier with ANPR controlled whitelist for under £200 I’m all ears!

Does this guy own a chain of chicken restuarants?
It’s nothing sexy like that, just stubborn people being stubborn!
 
Caporegime
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It is an absolute faff, even left unlocked with a deterrent. We have to do it at work outside the hours the site is open to the public and most people will just leave the gate open after a couple of weeks or so of doing it unless you keep on their case (and I hate doing it myself).

Probs less of a faff with a simple barrier that can just swing closed, I guess with a gate you've got to pull the thing back yourself, plus in this case, you'll have video footage/logs.
It's more just that if the key fob/combo thing is too much of a faff this sort of thing is an easier compromise as it could easily stop most random trespassers, I guess the issue is are the trespassers mostly random drivers or are lost of the instances some determined person who is in dispute/believes they're entitled to use the road in which case maybe it's not a deterrent to them.
 
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