Dedicated License Plate Cam project

[pozzello]

Product overviewNote: the standard does not contain camera

wonder what that means?... you sir, are braver than I.

i guess it makes sense tho that a decent 720p cam can be had cheap these days,
what with 3 & 4 MP cams pretty much the default...

 

[nayr]

I already messaged them, thats just a translation issue.. all its missing is the lens, and I am sourcing that separately anyhow..

my display monitor at my desk just went from 4 cams to 5, there is a blank in SmartPSS thats begging me to fill it with a 6th.. Dahua has not let me down so far.

 

[pozzello]

http://www.aliexpress.com/item/Vari-Focal-5-100mm-F1-6-360-Aperture-Range-1-3-Auto-Iris-CS-mount-DC/1767521328.html ?

 

[nayr]

yeah, or if I just wanted to go all out: http://s.click.aliexpress.com/e/b5duLB8U

and I am thinking I might just go for that, same level as my 12x Blackface and I know for a fact it can see the distances required.

attached is a image captured of the D1 substream on my blackface Dahua @ ~300ft and max zoom.. plate is completely readable if it werent for that pesky branch, the next image is maps showing distance of that shot with 120mm Low Res.

last image is the angle I am trying for, its really the best hope I have for a discrete view without trees/parking in the way.. since its dead on even asshats speeding like a motherfucker wont be a problem getting a crisp image of the plate. You can see the view intersects with the sidwalk at my neighbors driveway.. since nobody should be parking there it wont matter that my camera is low enough to get under the branches.

Anything else I think of is at too steep of an angle due to landscaping and buildings to get a good read while remaining discrete.. unless I put a "Bird Feeder" in the middle of my yard lol.

 

[pozzello]

a couple new data points:

1) Raspberry Pi (B+) is a no-go. latest rasbian overclocked at 900mhz. compiled openalpr and it takes 20 seconds to process the sample image (480x720 jpg of red golf with uk plate.) that's not gonna work. The windows version doesn't seem to have a 'daemon' option that i can tell. sigh...

2) The Huisun/Imporx v2 i just got does have secondary stream (704x480 or 352x240 but H.264 only) which i could have BI re-encode as mjpeg if i can get openalpr on a reasonable system in daemon mode...

 

[nayr]

its a bit better on my CuBox i4 (armv7 800Mhz Quad Core w/2GB Ram)

# time alpr -c eu --clock lp.jpg
Total Time to process image: 909.772ms.
plate0: 10 results -- Processing Time = 263.862ms.
    - H786P0J     confidence: 89.8356
    - H786POJ     confidence: 87.6114
    - HN786P0J     confidence: 85.2152
    - H2786P0J     confidence: 85.0755
    - H3786P0J     confidence: 84.8286
    - HS786P0J     confidence: 84.7763
    - H786PQJ     confidence: 84.7612
    - H786PDJ     confidence: 84.5669
    - HN786POJ     confidence: 82.9909
    - H2786POJ     confidence: 82.8513


real    0m5.698s
user    0m5.389s
sys    0m0.269s

vs my VM:

# time alpr -c eu --clock lp.jpg
Total Time to process image: 151.477ms.
plate0: 10 results -- Processing Time = 39.2637ms.
    - H786P0J     confidence: 89.8356
    - H786POJ     confidence: 87.6114
    - HN786P0J     confidence: 85.2152
    - H2786P0J     confidence: 85.0755
    - H3786P0J     confidence: 84.8286
    - HS786P0J     confidence: 84.7763
    - H786PQJ     confidence: 84.7612
    - H786PDJ     confidence: 84.5669
    - HN786POJ     confidence: 82.9909
    - H2786POJ     confidence: 82.8513


real    0m0.838s
user    0m0.780s
sys    0m0.056s

In the config I notice it has support for offloading to Nvidia GPU or OpenCL perhaps a low power atom system with a nice video card? I bet its floating point is crushing the cpu, this is arms Achilles..

 

[steve457]

I just received my 2032 camera and started messing around alpr. It appears that the daemon will use 100% of a CPU core for each stream you define. I just noticed that the documentation states that fact as well.

From the documentation:

"alprd needs at least one “stream” defined. This is just the URL for the mjpeg stream. You may use multiple streams on one server – each stream spawns a separate process that attempts to use a full CPU core."

I do not really want my server pegged all the time as it will impact the other things I use it for (Plex, minecraft, etc). What I'll probably end up doing is to have the camera FTP images to a directory on motion, and then write a Python script to monitor the directory and process the images. Does anyone have a Python script ready that does the processing and writes the results to a SQL database? If not, looks like I have another project to do. It would also be nice to have web interface to search the database along with some other features. It wouldn't be too difficult to put something together using PHP for the site. If anyone is interested in collaborating on such a project let me know.


Now I'm just waiting for my 25mm lens to arrive.

 

[nayr]

I have plans for such a project, just in NodeJS instead of python/php.. I am ordering my camera this weekend from China, I am going to just run the alpr daemon for a while to gather stats and start work on the data collectors and web front end, so it'll be a while before I start any code for processing motion events separately... then I'll run both side by side and make sure the motion processing is performing as reliably.

Ive abandoned PHP and Python in favor of NodeJS, its threaded and can handle the webserver, ui, database, openalpr, etc with ease.. I have some remote property I would like to deploy this technology on, have it sms me license plate numbers of anyone coming up the drive, but not if I cant get it to work on a really low power system that can be completely disguised in some rugged country.

 

[steve457]

I'm open to using other technologies as well. It is just that I'm familiar with Python/PHP, but in reality have not done any web programming in awhile. I'll look into NodeJS as well. It may also take me a bit before I start programming as I still need to get my 25mm lens installed and cameras mounted.

 

[nayr]

So this is going to be my ALPR camera: http://www.dahuasecurity.com/products/ipc-hf5421e-1004.html

I wont have to zoom so far in now with 4MP, but it is going to require more processing power, realized with my new plan this camera durring the day at least is my best chance of getting great face shots of foot traffic going by... I hope to use the facial detection feature to get images of pedestrians going by.

So with this camera I doubt im going to get good results with ALPRD sending it a 4MP stream, I am hoping the line cross feature will work well detecting cars at just the right moment for a snapshot.

Its a bit more than I wanted to pay, but since I have Dahua alarm IO programmed into my home automation system and I want a few physical motion sensors near this location and audio for non ALPR uses I decided it was worth the extra cost to get the extra features.. the line cross feature might just make this too easy and worth the premium.

I am still toying around with location ideas, I need to do some landscaping up front and my yard is raised so I am thinking of hiding it in inside a fake rock at the end of my front flower garden.. still gotta choose lens, 6-60mm or 5-100mm, the more zoom the worse it is in low light.. and that becomes important when you have shutter speeds real high for plates.. I'll probably get a 6-60mm first because they are very cheap, common and I can always upgrade if need be.

 

[nayr]

ok so I really like this hidden rock idea so I am going to push forward, here is the plan.. picture of rock garden shows conduit run to basement window then the location of a fake rock with a hole so the camera is orientated in the direction of the 2nd arrow.. I am hoping to draw the line detection approx between those mailboxes.

the other image shows the view taken from my cell phone at this location and edited for the FOV I am shooting for.. to that white mailbox on the left side is ~195ft so I am thinking of pairing the camera with the 5-100mm lens option.

What sold me on the faux rock:

• Completely Hidden, not making neighbors nervous that I am gathering plate data.. still only have 1 slightly visible cam from the sidewalk
• Install a post in rock garden, attach junction box and camera to it.
• Can hide mini external mic in surface of rock.
• if I need external IR I can hide it too inside the rock
• protects it from the elements
• very short run to basement that will be completely hidden when complete.
• its right in the middle of my last blindspot, while it'll be zoomed far away it'll be quick work to attach some outdoor motion sensors so my PTZ can check out any activity close to my big living room window.
• low enough I get under all these trees to see distance.
• roughly head height of foot traffic, little bit lower so can see under hats.

 

[zero-degrees]

ok so I really like this hidden rock idea so I am going to push forward, here is the plan.. picture of rock garden shows conduit run to basement window then the location of a fake rock with a hole so the camera is orientated in the direction of the 2nd arrow.. I am hoping to draw the line detection approx between those mailboxes.

Should make for nice placement and capture as long as no one parks to far down in the driveway or on the street blocking the view. This is close to the perfect view. Be interested to see compleated install pics when you're done.

 

[pozzello]

that field of view looks too wide to get useable plate captures.
you'll need ~100 ppf or greater for anything close to reliable automated plate capture.
you'll probably need something more like what i've marked here:


but it sounds like you'll have lens options to achieve that...

 

[steve457]

I like your idea of using the cameras hidden in a rock, and think I will now also use that idea! I was planning on hanging two mini-bullets on the corner of house around 9' up, but never liked the fact that they would be so obvious. I can also get away with using some fake rocks, the only drawback being that if someone was parked in the driveway they would block the view. I'm ok with that though, since our driveway is clear 95% of the time and would rather keep the aesthetics looking nice.

 

[nayr]

@pozzello, you think so even with 4MP? I am going to be working with a 2688×1520 resolution in that frame.. but maybe your right, thats why the box camera so I am not locked into a lens or location that just dont work.. I'm not going to use the daemon on a low res mjpeg, id rather try to grab a few full res snapshots and add em to a queue.

@zero-degrees, luckily thats about as far back as they ever park.. they were unusually far back today which was good for my imagination.. when they have cars park on street they are on other side of tree to the left, anyone parking on this side of tree would be blocking end of there drive.. and there is another driveway like 8ft on the other side of that one with there mailboxes in the middle so nobody parks on the far side either.. I think the biggest blockage is going to be there lawn care guys or perhaps sprinklers very early morning.. but I can cope with it, I am not expecting 100% success 24/7/365.. as long as I get a good majority of it.

If I go up any higher to see over cars then I have to start butchering my neighbors trees all ninja like without pissing em off lol.. over about 6ft high in either direction are blinders that end up with nearly 90 degree offset angles that will never work.

I been trying to come up with something, been crawling on roofs and setting up ladders and starring at the street from every angle I can get.. I am not willing to mount one in a tree, especially with any zoom.

 

[pozzello]

a 50mm lens on a 1/3" 4MP imager gets you about 6 degrees FOV, or about 20 feet wide at 200 feet, for ~140ppf.
that sounds like it could work, but will be more like the rectangle I drew than your full frame...

you can play with all that here, btw: http://ipvm.com/calculator

 

[nayr]

thank you I lost the bookmark for that site, man that would have been helpful ive been working it out in my head haha

glad I opted for the 4MP else I'd of needed one for each lane with 720p, well I am glad to know I dont need anything better than 60mm after looking at those numbers..

 

[ruppmeister]

So being that low to the ground, aren't you risking it being covered on days where there is any measurable amounts of snow? Or not a big deal if a couple days a year you can't use it?

 

[nayr]

there is actually a 4ft eave over this garden, never seen it drift up here so I doubt it.. but nothing I cant cope with.. if I get that much snow I have to move it within 24h off my sidewalks.. after the camera is clear hah.. im going to get a pretty tall faux rock try to get the camra over a foot off the ground near the peak.

other than the obvious security advantages I kinda want to use this for a bit of automation, like warning me code enforcement is out or my parents are pulling up to the house unannounced or Chinese food is here, package delivery people, etc.. but the driving factor comes from me being the suspicious type I tend to go for a short walk when I see odd behavior and try to discretely take a pic of a plate with my phone as I pass on foot, believe it or not its came in handy many times when a neighbors shady contractor just up and disappears.

Lots of burglaries going on lately and I feel this will really expand the local security if any happen near by and I can provide an ID.

Then we have the repeat offender assholes who need to be reminded they are in a residential area, my neighbor put up a kid at play flag at the end of there driveway when kids were playing street hockey.. asshole speed by honking his horn flipping everyone off. He continued the stupid behavior until I managed to grab his plate number.. gave it to the kids next door and the behavior stopped.. was some teenager a few blocks away taking the "backroad" home at highway speeds.. There have also been a few instances of senile old neighbors loosing there marbles and going arround and screaming at anyone they dont like.. im not going to be policing anyone, just covering my bases so those fuckwads up to no good wont see it coming.

the lens I went with should look like this but say 1:1.4

6-60mm (10x Zoom) F1.4 1/3" IR Corrected Auto Iris Vari-Focal

 

[steve457]

How are you planning on mounting the camera through the rock, just cut a hole large enough for the lens to poke through or be recessed behind? Also, are there any negative consequences of having the camera mounted so low in terms of glare from cars headlights that would be less of an issue if camera was mounted higher up?