The old and busted mailbox at the front of my driveway was leaning forward, rotting, and had paint peeling off of the black, then painted gold, then black again metal. None of the wood was pressure treated. This just would not do! I also wanted to continue fortifying the house with security cameras by wiring up some Automatic License Plate Recognition cameras (ALPR).
I found a few pictures of mailboxes I liked online but couldn’t find any plans for building something other than the de facto ones seen everywhere. I started with a 4″x6″ piece of treated lumber and wrapped it with cedar, known for it’s ability to withstand the elements Indiana could throw at it.
You might ask yourself “Matt, why is the backside of the mailbox so long?” Good question! I am planning on hanging a lot of flowers off of the back to keep it visually appealing during the spring and summer months!
We received a mailbox as a wedding present, an odd gift we actually asked for. It’s large enough to fit medium-sized Amazon packages, keeping my USPS mailman from having to run the packages to the door, and boy do I like ordering things from Amazon.
After I got the cedar affixed to the frame of the mailbox using triple coated deck screws I sealed up the nooks and crannies with silicone caulk. Silicone will last longer with the wood expanding and contracting under rain, sun, and snow. As I was sealing up the sides of the frame I wired up the light at the top of the mailbox. It would eventually be powered by the dawn to dusk light sensor in the light post near the center of the yard. I placed a 2 gang waterproof outlet directly under where the mailbox sits on the frame, to be used for Christmas lights or powering electrical tools when I am in that part of the yard.
After two primer coats and two top coats the mailbox was ready to go outside. Unfortunately it was still January, way too cold for pouring concrete. As pictured, you can see the conduit I would use to run the 110v line and the network cables for the security cameras. I left the middle portion of the frame uncovered by cedar, to allow the cameras to be mounted directly to it. I hoped it would create a more professional final look.
In February there was a weekend where the weather cooperated with me. I dug out the old busted mailbox (which cracked in half when I was removing it), dug down another foot, and planted the new hotness in the hole. I wanted to go 3 feet into the ground, but the gas line actually went directly under the mailbox. Remember to call before you dig, especially in an easement where utilities are run. I used two bags of concrete to fix the mailbox in place. I accidentally used too much water mixing it in the hole and had to wait a while for it to cure.
On the backside of the mailbox I installed a simple weatherproof box to house the wire termination coming from the house, as well as a network patch panel to connect the cameras to. In it is also another 1 gang outlet (it came with the box, so why not use it?) that would be powered by the dawn-to-dusk sensor. The Hikvision Hikvision DS-2CD2T42WD-I5 camera was just laying on the box. It was too large to fit on the front and get the angle needed to see plates.
On the front side the cameras were mounted directly to the frame of the mailbox. I was still experimenting with different camera styles, IR illuminators, and focal lengths for gathering license plate numbers. Until I was finished I wasn’t worried about painting this section. The wires for everything ran through the center of the mailbox to the backside of the weatherproof box. Keeping all of the terminations and connectors in the box away from the weather would make them last longer. I ran two different holes 4″ apart, one for network wires, the other for high and low voltage. The cameras are powered via PoE, a most wonderful invention that meant each camera didn’t need a separate power supply at the mailbox.
In this picture I am trying out the Hikvision 6mm 4mp camera with an external illuminator that could output enough IR to illuminate license plates. After installation and looking at it for a few days I decided it stuck out too much and didn’t look very good inside the box. I thought that a turret style camera might work better, like Hikvision’s new low-light cameras that had just come out. I am still awaiting it’s arrival to try out.
I put a 60 watt LED bulb in the light, which matched the light post in the yard. This image was purposely overexposed, the light isn’t actually bright enough to keep anyone awake at night đŸ˜›
I grabbed a mailbox sign off of Etsy. I wasn’t too pleased with the finish quality, it scratched off when I accidentally scraped it with a screw. A quick touchup with a permanent marker made it look good from the street though. I still need to cover the screws to help them blend in also.
Here is a quick video of a car passing by during the middle of the night. I have some focusing to do with the camera (the IR cut filter throws off the focus during the night). I think I will leave the camera constantly in night mode because it’s not a varifocal and I’d need to adjust
So I am currently waiting for a camera to arrive from AliExpress, I’ll update the post when I have more content to provide!
9/26/2017 Update:
Several months have passed since the completion of the project. I’ve switched to a different camera, the 12mm Hikvision DS-2CD2325FWD-I, a “low-light” model. It sports a larger sensor and smaller pixel count, so it performs better at night than the average IP camera. It also has EXIR built into it similar to the other Hikvision turret cameras, meaning I no longer needed the external IR illuminator. I’ve found the turrets to provide ample light on their own. I am currently running a 1/1000 second exposure with the gain set around 10-12. I pushed the cameras further away from the base of the mailbox with some treated deck boards to give the cameras a more parallel view of the road and to reduce the glare of the IR on the mailbox itself.
I am capturing plates very well.
This is 10 FPS:
15 FPS with a driver who went into the yard which made his license plate HUGE on screen:
6/24/2022 Update:
I upgraded to Dahua IPC-HFW5241E-Z12E cameras for better IR output, and also tied it in with my OpenALPR Processor Tool to overlay plate data on the camera’s feed:
I am looking at doing this. Where are you at in this project? What SW are you using for ALPR? Have you considered using a filter (filter everything in the visible range)? Thanks!
I updated the post with the current hardware that is installed and some new capture videos.
Right now I’m not using anything to automate it, just reviewing the tapes whenever anything strange happens. I did have luck with http://www.videoanalitika.lt/en/index.html and http://www.openalpr.com/ though.
I assume you’re suggesting the filter to make the ALPR processing easier on the computer, to get better results? I haven’t tried that. Part of the light that comes from the license plate is from the car’s own license plate illuminator, it would be interesting to see what the plates look like with only IR illumination.
This is awesome