Dedicated License Plate Cam project

[nayr]

@cball, not really I am using the lens as a mount sorta.. rests in the hole and a bolt in the back is tightened or loosened to raise/lower the angle.. I did a walk test today and it was nothing more than a birdhouse from the sidewalk and I know what to look for, so no need.. I also did not want it to look unusually large so I packed it in there with minimal tolerances.. the ir spotlight is going to soak up the little space left.. the awning goes down past the lens, so unless your looking dead on you wont see it even up close.

@SyconsciousAu, >90% transmission that's exactly what I was looking for.. a spec sheet, cheers.. presuming IR is more than adequate I'll put one of those to cover the IR in the day.. paint the front black so its not obvious.

 

[nayr]

Ta-da! still needs a paint job but it's installed.. secure mounting, no wobbles and its high and dry.

3ft off the ground should help with snow storms.. having a bunch of tools on hand made this fairly cheap too, think I paid about $40 for all the fittings and lumber.

left right adjustment is obtained by turning it, its very tight but I left a bit of play in either direction so you can get a few degrees either way, with time I am sure it'll weld its self into this position.. up and down adjustment is obtained by raising and lowering the back end of the camera.. I am thinking of bolting the IR directly to the camera so they are both aimed vertically with the same mechanism (not pictured)

I didnt crimp an end on it right now because I need to pull the cable out to paint it.. so jammed a punchdown box inside with excess cable since there is no IR under there now.

end result: I am very happy, this is much more inconspicuous than just bolting a camera to the wall at this location would have been.. When I plant new shrubs out front it'll just fade away and vanish.. would have loved to put it under the eaves, but that would have required trimming my neighbors tree to get this view..

4 cameras viewing the front yards, and all of them are hard to see from the street even if you know where to look, yet all still extremely effective.. yay for zoom! screw wide angles

 

[nayr]

@SyconsciousAu, got that IR filter the other day.. its awesome!

had all kinds of fun looking at the sky through it in the day, looks really awesome in IR.. then tonight I went outside to see if it'd block much noticeable IR.. I could pass it back and forth infront of my cameras IR and it had no impact on brightness that I could tell.

now for the IR light to get here..

now that its in the birdhouse and I have it perfectly focused and framed up I created a much smaller mask, ive got the image processing time down to under 1/4s and I get most everyone framed up at the same point, with 2 snapshots just feet apart... reading accuracy is awesome and I get all of the vehicle in frame.

got it up just in time, already survived a few hard rains.

*edit*
ALPR Results for these images:

# alpr --clock *.jpg -p co
Total Time to process image: 212.834ms.
plate0: 4 results -- Processing Time = 31.3253ms.
    - 346RJH     confidence: 88.3631     pattern_match: 1
    - 346RIH     confidence: 75.5083     pattern_match: 1
    - 346RJM     confidence: 74.222     pattern_match: 1
    - 346BJH     confidence: 72.83     pattern_match: 1
Total Time to process image: 200.6ms.
plate0: 10 results -- Processing Time = 32.4988ms.
    - 123WUH     confidence: 91.3175     pattern_match: 1
    - 123NUH     confidence: 83.9763     pattern_match: 1
    - 123HUH     confidence: 82.9157     pattern_match: 1
    - 123UUH     confidence: 82.5502     pattern_match: 1
    - 123MUH     confidence: 82.4574     pattern_match: 1
    - 123WOH     confidence: 78.8516     pattern_match: 1
    - 123WDH     confidence: 78.3965     pattern_match: 1
    - 123WUM     confidence: 76.637     pattern_match: 1
    - 123NOH     confidence: 71.5104     pattern_match: 1
    - 123NDH     confidence: 71.0553     pattern_match: 1
Total Time to process image: 216.576ms.
plate0: 3 results -- Processing Time = 33.83ms.
    - 274SVE     confidence: 83.9489     pattern_match: 1
    - 274GVE     confidence: 78.082     pattern_match: 1
    - 274BVE     confidence: 77.3503     pattern_match: 1
Total Time to process image: 243.026ms.
plate0: 3 results -- Processing Time = 36.8507ms.
    - 059RTQ     confidence: 91.2683     pattern_match: 1
    - 059RTO     confidence: 88.5464     pattern_match: 1
    - 059RTD     confidence: 87.496     pattern_match: 1
Total Time to process image: 245.918ms.
plate0: 10 results -- Processing Time = 32.2625ms.
    - 422EQX     confidence: 89.8069     pattern_match: 1
    - 422EOX     confidence: 80.196     pattern_match: 1
    - 422EDX     confidence: 79.85     pattern_match: 1
    - 422CQX     confidence: 77.2121     pattern_match: 1
    - 422EUX     confidence: 75.7989     pattern_match: 1
    - 422EBX     confidence: 74.8747     pattern_match: 1
    - 422EGX     confidence: 74.4453     pattern_match: 1
    - 422COX     confidence: 67.6012     pattern_match: 1
    - 422CDX     confidence: 67.2552     pattern_match: 1
    - 422CUX     confidence: 63.2041     pattern_match: 1
Total Time to process image: 228.72ms.
plate0: 2 results -- Processing Time = 32.9159ms.
    - PBR433     confidence: 90.5493     pattern_match: 1
    - FBR433     confidence: 74.8516     pattern_match: 1

 

[hamsoplo]

Great job, I'd like to give this a try but my state doesn't have front plates so I'd need 2 camera's or just miss half of them. And my house seems be be set a bit farther back from the street has kept me from trying. That trex birdhouse might go blend well into a planting bed in the front yard enough for me to give it a go.

 

[SyconsciousAu]

@SyconsciousAu, got that IR filter the other day.. its awesome!

Ive also heard of those filters being used in front of the camera, with the camera being left in night mode all the time, but Ive never seen it done. Any chance of posting up a few shots of what that looks like?

 

[nayr]

yeah I thought about that, it'd take care of the poor IR correction on out of focus objects thats for sure.. but I like being able to identify the vehicle color, at least in the daytime... im going to be grouping matching license plates on database backend so I just have to catch the vehicle once in the day to know what color it really is.

When the IR spotlight gets in I'll put it infront of the lens for a few shots to to show how it'd work.. until the spotlight comes I am not touching it, got it focused and framed perfectly.

forcast a bunch of snow this weekend, so I'll get some all weather testing in early.. bring it on.

edit: estimated ir delivery date, 4/21

 

[j4co]

Interesting stuff.

As for the images in post #183

is that the size of the license plate that open alpr can scan reliable?

 

[nayr]

those plates are ~100px tall at smallest, much smaller and the reading reliably goes to crap.. but it's pretty good right here.. when you get to about 150 pixels in height it's reading with perfect accuracy unless something else interferes (plate damage, trailer hitches, bike racks, etc)

Updated the post to show you the output of OpenALPR on those set of images.

There is over a foot of snow on the ground today (~17in in places), and the ALPR camera is still reading pates.. well kinda, most plates are snow packed and unreadable, getting more false triggers from high contrast patches of snow, and there is so much light that even 1/1500 is ghosting.. I can put it at 1/10000 today and its still nice and bright.. the important thing is its not buried in the snow, so once road gets better it'll get right back to reading.. not much traffic on days like these.

with the big overhang on the front of my house, it appears the birdhouse is still nice and clean.. you can see it in the attached photo sticking out from the side of the end of the house.. The front yards are a foot higher now, I think if I had gone with the faux rock it would not even see the road today.. the neighbors grass was just in the bottom of the frame in my early pix.

 

[j4co]

Thanks, here is the situation.


We have lots of car break in where they take the navigation, air bags etc.
They open cars withouth breaking in. Seems to do it with a laptop with receiver near shopping centers and gas stations, where they copy the hand sender codes.


So we have visitors in the middle of the night some nights.


We live on a artificial island:





There is one entrance road for cars: black arrow
There are 2 walking/cycling bridges to adjecent islands.


The person who wants to scan the license plates lives at the red cross. He put a camera on his roof (like 9 meter high) and during daytime he can read the license plates by manual looking at the images. During night nothing as the ir of his camera is not reaching that distance. Edit: he views the street like 40-50 meter away, not the island entrance.


I live at the blue cross.


The yellow line is the wall seperating our garden from private parking space (in between wall and road) this is like 3 meter high wall.


So my ptz which will be at 8-9 meter up should just be able to peak over that wall near the entrance of the island. But there are multiple 6 meter high trees, and this will block the view most likely.


So we might end up doing it both for not to much money if possible, and cover 2 of the 3 streets.
I looked at the links and a 1.3 or 2 mp with 6-60 mm lens seems affordable.
The streets are relatively small, like 4 meter, and the official max speed is 30Km/H


Could a celeron 847 at 1.1 GHz do it for OpenAlRP ? (With 1.3 or 2.0 MP that is)
Other option is a socket 1155 board i have with i3-3240, but this consumes much more energy.

 

[nayr]

I think this could run reasonably on a lower power system if, you went with 720p instead of 1080p.. it would require more zoom, you'd get less of full vehicle shots like I am getting and more just bumper/plates.. fyi im not detecting motorcycle plates or anything with this framing.. those are much less than 100px for me, but not a priority.

an ALPR camera has to be dedicated to LPR at night, you'll never see anything but headlamps.. needs good IR, I'll find out this week if the IR I ordered will be adequate for my distances.

what distances are these? you can use google maps to measure distance.

you can go ahead and install OpenALPR on your Celeron system and see how fast it runs through my images, ive posted the performance results of my Opteron you can compare it to along with my mask.. getting it under 300ms really improved performance for me, at 900ms it could miss cars or get them in hard to read positions.. without the mask I am at ~900ms, with the mask I can get every plate that passes through my mask no matter how fast the person is going at a mere 6fps

you could crop those images down to 720p, leaving everything the same scale and try it again to see how the same image with a bit more zoom @ 720p would run.. you'd need to crop all the images and the mask the same way too.

 

[j4co]

I could measure at 25 meter as the road is in a curve, and from my wall (perhaps to high) i would have the required angle easy at that distance.

edit: it would not have to be 25 meter, it could also be 15 or so.
the road is in a curve, and our garden wall is 5 meter away from the road, so the 30-40 degree angle is really close basically.

you once posted these:

http://nl.aliexpress.com/item/1-3-6...mera-CS-mount-Lens-View-Angle/1782359109.html

http://s.click.aliexpress.com/e/blYkoFHA

price wise interesting for me.

 

[nayr]

you might want a lil more zoom than the 60mm would give you @ 720p, might go the safe bet and get a 100mm: http://nl.aliexpress.com/item/Vari-...nge-1-3-Auto-Iris-CS-mount-DC/1767521328.html

I did not go with that camera because it was: Chinese language only, and low light performance of that chip was kinda crappy.. but at closer distances with more zoom, it should still do the job.. just might need alot of IR.

BLC is the important thing for my environment, I thought I'd use the WDR but it just fuzzed up plates too much.. so BLC is needed for daytime reflections.

 

[j4co]

There are soo many products there, i loose track
So i will have to look for auto iris and BLC

Edit: if smaller distance would something like this also do:
http://nl.aliexpress.com/store/prod...-265-HEVC-POE-IP-CCTV/319147_32462001588.html

this seller is listed in a thread as reliable, and multi language versions.

Can be had with 12 mm lens.


edit: photo of about 2 meter high with ipad.



The lamp post is like 20 meter away. There car lights would beam into the camera.
half way the 30-40 degree angle would be i think.

edit: my better half (wife) does not agree on more cameras. So will solve it with the ptz if needed.

 

[nayr]

IR Spotlight came in today, got it fitted and just waiting for it to get dark out..

 

[pozzello]

a birdhouse with a view...

 

[nayr]

it looks like the IR spotlight is a winner @ 1/500

its a pain to setup at night, my FOV is all out of wack.. but I got it to read a plate, needs some adjustments and tweaks but it'll work just fine.

 

[SyconsciousAu]

When you say the Field of View is all out of whack what exactly happened? I found I was getting some severe focus shift between night and day, even with expensive fujinon IR corrected lenses.

 

[nayr]

oh i mean its extremely difficult to line up the FOV in the dark and adjust focus with shutter speed at 1/500.. hah

i had my test plate out there, as you can see in the 2nd pic above..

I tried to set it all up durring the day, but I had the IR focus backwards.. was on wide angle not tight focus so I had to take the birdhouse apart, fix that and put it back

the birdhouse contraption is not the easiest to tweak, everything has to go together very specifically.. I am painting it up today, the camera will be offline.. but I need to paint the pole and crimp the ethernet cable end on tonight.. but once its setup it should stay put and just run.

 

[nayr]

painted, installed, with IR.. everything wired and self-contained out of the elements.. even has an amplified microphone for my recordings.

had to shave the inside in a few spots to make room for the camera, but you'd never know unless I told yeh.

 

[pozzello]

so the IR filter still lets some visible red thru...