Hikvision Dedicated License Plate Reading

[mlapaglia]

I am building a new mailbox for my house and want to incorporate some cameras dedicated to license plate recognition.





I am currently trying to use a DS-2CD2032F-I 6mm with varying amounts of success. Newer license plates reflect just fine, but older ones are quite blurry.





I realize 6mm is too wide of view for a camera dedicated to license plates.

I know many people try to do this from their house instead of at the street side, and wanted some input on what camera would work best for this. Would 12mm be enough, 16?

I can view the IR being emitted from another camera that faces the mailbox:


That bullet doesn't reach very far, which I think is most of the problem.

The bullet is set to:
DNR - 20
Exposure - 1/250
Gain - 54

I have a Hikvision NVR and would like to stay in the family if possible.

I am wondering if DS-2CD2T22WD-i8 16mm would be a good fit. I have the 4mp version and the EXIR on it is fantastic! I am having trouble finding the 16mm version on ebay, ali, or amazon.

I have a blog post with all the details and more pics: DIY Security Mailbox

 

[nayr]

external IR wont do anything for you unless its at the cameras location, retro reflectors only send IR back to where it came.. so if you move your IR a few feet away it looses all capabilities for plate reading.. you do need more IR if your struggling at 1/250.

a 12mm 4MP should do just fine, keep an eye on this thread as I'm about to do a bunch of tests with 4MP 12mm for LPR use and determine its useful range... its not your same camera but should apply fairly closely.

 

[mlapaglia]

I didn't mean I wanted external IR, just to show an example that you could see what the bullet is putting out onto the street, which isn't a lot.

The i8 has 4 huge LEDs in it. This side of the house is pitch black. I assume it would work fine by the road for plates.



DS 2CD2T42WD I8 English version 4MP EXIR Network Bullet IP security Camera POE, 80m IR, 120dB Wide Dynamic Range, H.264+-in Surveillance Cameras from Security & Protection on Aliexpress.com | Alibaba Group

12 or 16mm.. hmmmm

 

[nayr]

you didnt include any of the distances in your original post, but I tested 4mp@12mm does just fine up to 40ft so far, presuming you have adequate IR.. Im setting up a 25mm for ~100ft, and I have a 60mm on 180-200ft

I really doubt you need 16mm, or just get a varifocal

 

[pepperfr]

The bullet is set to:
DNR - 20
Exposure - 1/250
Gain - 54

Just for kicks before you give up on your 6mm bullet, I would try exposure at 1/500 and 1/1000. Obviously everything will appear much darker in the image generally, but you may find that the plates are more readable at those exposures. I'm not an expert, but it looked like the plate IR reflection was kind of overpowering in some of your examples. In my limited experience that can make it harder to read the non-reflecting characters on the plate. On a dedicated LPR, its those characters that are important.

 

[mlapaglia]

Here's 1/500

 

[mlapaglia]

I couldn't find the i8 from ali that wasn't a supplier celebrating the new year, so I get two different cameras to try.

The i5 Amazon.com : HIkvision DS-2CD2T42WD-I5 English Version 4MP EXIR Bullet IP Camera POE IR 30m 12mm Longe Range Lens : Camera & Photo
and the 4mp 12mm bullet: Amazon.com : HIKVISION V5.3.3 4MP International Version POE IP Bullet Camera Security DS-2CD2042WD-I 12mm firmware upgradeable : Camera & Photo

Should be here tomorrow. I expect the i5 to blow the bullet out of the water with EXIR, but the i5 is also the size of a small tank.

 

[pepperfr]

Here's 1/500
View attachment 14465
View attachment 14465

Yeah, you need some more IR.

 

[nayr]

and PPF

 

[mlapaglia]

Got the bullet on one side of the mailbox and the larger bullet on the other side



Still have some pointing to do


Much better picture. Now just need to see how the IR is at night.

They are both running at 1/1000, 10 fps, constant 8196kbps, H264 with the gain set at 10.

I noticed enabling the h264+ caused a lot of issues with the video stuttering when a car goes by. Probably because it's taking up the whole frame and Hikvision's h264+ implementation sucks. I've disabled it for now.


Edit: The nightman cometh

 

[mlapaglia]

It looks like at night there is some issue with focusing. Why is the license plate so blurry? It appears like it does get sharper as it moves away from the camera.

 

[nayr]

video is private; license plates appear closer than they are when flared up by IR.. this is why I been urging the use of varifocals.. you might have to manually focus this at night on plates.

 

[mlapaglia]

Sorry you should be able to see it now. The plates in the video are about ~20 feet away from the camera, wouldn't that distance be enough where the focus would be pretty close?

I'm currently keeping the cameras in night mode 100%, the license plates are in sharp focus during the day. Could this simply be shutter speed too slow, not enough light, and the exposure having to compensate creating a noisier image?

 

[tywest]

Could you post a pic of the mailbox?

 

[mlapaglia]

I added an IR light to the smaller bullet. Amazon.com : CMVision IR110 - 114 LED Indoor/Outdoor Long Range 200-300ft IR Illuminator With Free 2A 12VDC Adaptor : Infrared Motion Detectors : Camera & Photo

before:


after:


Here's the current shape of the new mailbox. Just waiting on some warmer weather to get it buried.

 

[Bradmph]

That is a hell of a mailbox holder. How does your mail arrive again, By missile? lol., How are you cloaking your camera in that, just curious. I was thinking of installing a camera in a bird house or 2 inside a retaining wall block between driveway and the property. I want to get sidewalk traffic clear close facial shots.

 

[mlapaglia]

It's 4x6 treated lumber lined with 1x8 cedar, so yes rather large. I'm putting a decorative light at the top of it and an oversized mailbox for receiving packages.
The cameras are going to be painted brown to match the post, and mounted right below the electrical outlet you can see in the pic. You won't see them unless your're looking for them, but they won't be totally hidden.

 

[nbstl68]

I am planning to trench a CAT6 right to the mailbox. That would give me view of the road right at the road in either direction. Sothe cars woul pass within just a few feet. What size mm focal length would be appropriate for that?
Should I plan to try to focus right as a vehicle nears the box on the way by or further down the road?
This is about 200'. I understand CAT 6 can go 300' with POE...But would I expect any power issues at that length? My switch does full 15 w to each port but I assume there would be some reduction but enough to make any difference?

 

[hmjgriffon]

I am planning to trench a CAT6 right to the mailbox. That would give me view of the road right at the road in either direction. Sothe cars woul pass within just a few feet. What size mm focal length would be appropriate for that?
Should I plan to try to focus right as a vehicle nears the box on the way by or further down the road?
This is about 200'. I understand CAT 6 can go 300' with POE...But would I expect any power issues at that length? My switch does full 15 w to each port but I assume there would be some reduction but enough to make any difference?

You are good to go for 100 meters, about 328 feet with no power issues, as for lens I'd go varifocal and test it, make sure your frame rate is high enough.

 

[nbstl68]

I'd like to use as small and inconspicuous a camera as possible as I'm sure unless I made some type of hidden enclosures neighbors would complain about their privacy as we have a lot of retired walkers that would not want to be on camera and \ or stand out as a temptation for someone to grab since it is right at the road. Even though I only want to see plates, not people.
Any particular small cam suggestions?

It would be great if one of those mini IR POE cams could work for this which I could just hang and disguise as a reflector on the bottom post...can't find a mini +IR+poe+varifocal though.


Would it be best to try to capture car plates when the car is closer to the mailbox or a little further out?
I saw from reading this thread I would probably need to try to pick a specific distance and try to test and manual focus on the selected spot maybe with someone holding a plate at a particular distance.
Without a varifocal I assume closer would be better as the plate would be larger?
Speed limit is 20 mph..which of course means cars typically go by around 30+mph.