Hikvision 12mm cam won't read plates

[Geneyus 0]

I have a 12mm Hikvision 2032 bullet camera that points towards the end of my street where cars pull up to the stop sign. The cars are probably going 10-15 mph as they pass through the camera view, but the camera hasn't been able to pick up license plate numbers. The license plate is always blurry.

I have the frames per second set to "full frame" on my Hikvision NVR and the quality all the way up (5 boxes out of 5 in settings). What else can I do to make the license plates not blurry during daylight hours? The car takes up a good portion of the screen, so I feel like the license plate should be a little more clear on vehicles going so slow. Am I asking too much?

 

This is the view when I do the digital zoom:

 

This is the normal view on the Hikvision 7604 NVR:

[1Diesel 0]

I have a 12mm Hikvision 2032 bullet camera that points towards the end of my street where cars pull up to the stop sign. The cars are probably going 10-15 mph as they pass through the camera view, but the camera hasn't been able to pick up license plate numbers. The license plate is always blurry.

I have the frames per second set to "full frame" on my Hikvision NVR and the quality all the way up (5 boxes out of 5 in settings). What else can I do to make the license plates not blurry during daylight hours? The car takes up a good portion of the screen, so I feel like the license plate should be a little more clear on vehicles going so slow. Am I asking too much?

 

This is the view when I do the digital zoom:

 

This is the normal view on the Hikvision 7604 NVR:

it looks like you have to much of an angle. The tighter you can keep the angle the more time you have to get the image. With a 12mm your only going to be able to be 20 or 30 ' away depending on lighting and angle. Ideally you want the plate to take up as much of the image as possible so you have more pixels on the plate.

I use a 2032 as well,but put a 25mm lens in it mounted under my mailbox. It does a decent job for what it costs.

[steve6690 0]

I'm a user of licence plate capture systems as part of my job. IMHO you might get away with the angle your camera is at but not at that distance. Ideally you want to be as head-on as possible. and high enough that any IR illumination will not reflect straight back at the camera off the licence plate. Vehicles on a road will pass along a fairly narrow path through your cameras image so it shouldn't be too difficult to fill the frame a bit more with the licence plate.

All fixed licence plate cameras I work with are either directly overhead on motorway gantries or on poles no more than about 10 feet from the edge of the road.

[Geneyus 0]

it looks like you have to much of an angle. The tighter you can keep the angle the more time you have to get the image. With a 12mm your only going to be able to be 20 or 30 ' away depending on lighting and angle. Ideally you want the plate to take up as much of the image as possible so you have more pixels on the plate.

I use a 2032 as well,but put a 25mm lens in it mounted under my mailbox. It does a decent job for what it costs.

 

I didn't know there was a 25mm lens for these. I knew about the 2.8, 4, 6, and 12mm. I don't think I can get the camera any closer to the road without mounting it to a tree and running ground wires. I think the distance from vehicle to the camera in the above picture is about 70-80'.

 

I'm a user of licence plate capture systems as part of my job. IMHO you might get away with the angle your camera is at but not at that distance. Ideally you want to be as head-on as possible. and high enough that any IR illumination will not reflect straight back at the camera off the licence plate. Vehicles on a road will pass along a fairly narrow path through your cameras image so it shouldn't be too difficult to fill the frame a bit more with the licence plate.

All fixed licence plate cameras I work with are either directly overhead on motorway gantries or on poles no more than about 10 feet from the edge of the road.

 

Yeah, it's sounding like the angle + distance is just too much for the camera. That's what I was afraid of. I'm going to try moving the camera over about a foot and directing it at the stop sign where the vehicle stops. If that doesn't work, it probably isn't going to happen from any location on the house.

[ssmith10pn 0]

At that distance you would need a 40mm lens.

[MaxIcon 0]

Here's an inexpensive 25mm lens I use on a Hik 2032 for plate capture:

http://www.ebay.com/itm/25mm-1-2-inch-Cmos-MegaPixel-Board-CCTV-PC-camera-Lens-M12x0-5-for-MT9P031-/121375945476

 

It's 1/2", so you get more zoom than you would with a 1/3" 25mm, which is a good thing. It's not a great lens, and has some chromatic aberration, but is decent overall. Changing lenses is a pain on the 2032, so be sure to focus it at the right location while it's apart.

 

I had to use slightly longer screws to install my sensor board, as the lens is just a little too long and touches the end glass before the board is seated, but it's held up fine over a number of months. Because of this, you can't fit any longer lens on this camera without some major mods.

 

Mine works fine in daylight at about 80-100'. Once the light drops much, the image quality drops as well, and you can't read plates any more. The cam's IR is nowhere near strong enough for that distance.

 

To get an idea of what you need, save a snapshot of the cam at full resolution with a plate in view. Open it a paint program, and see how many pixels wide the plate is. A US plate is 1' wide, and you need at least 60 pixels per foot to get a decent image for plate recognition.

 

As 1Diesel pointed out, you have a lot of angle there, so the actual plate width is less than a foot, but you need more pixels per foot in this situation, so the same measurement is meaningful, even though the plate image isn't a foot wide.

 

The full screen image you posted is about 950 pixels wide, and the plate is about 25 pixels wide, so that's 2.6% of your horizontal resolution. It looks like the plate is about 20 pixels wide in the full screen shot, but it's hard to say what the NVR is doing to the image.

[jeromephone 6]

google some dedicated LP capture systems and see what kind of hardware and software they use. Some LPR systems have special software to deal with reflective plates and IR problems. The info you get may give you some ideas on lenses and frame rates.

[SyconsciousAu 0]

I have the frames per second set to "full frame" on my Hikvision NVR and the quality all the way up (5 boxes out of 5 in settings). What else can I do to make the license plates not blurry during daylight hours? The car takes up a good portion of the screen, so I feel like the license plate should be a little more clear on vehicles going so slow. Am I asking too much?

 

Remember the car is moving almost perpendicular to the lens at 15mph. What that means is the plate numbers are moving almost 6.6m (27 feet) left to right every second which causes some serious motion blur.

 

No if you are serious about doing plates you need to get your camera closer to the road so the plates are moving as close to straight at/away from the camera as possible.

 

If that is not possible you need to reduce the amount the plate moves during the frame by increasing your shutter speed.

 

First force your camera into black and white night mode in the menu settings (Configuration > Image > Day/Night Switch). Turn your gain up as far as it will go. (Configuration > Image > Exposure Settings)This will maximise the sensitivity to light. Now set your max shutter speed to 1/4000 (Configuration > Image > Exposure Settings). If this makes the image too dark lower it to 1/2000 then 1/1000. At 1/1000 the plate is now only moving 6.6mm (1/4") in each frame relative to the camera in each frame. If you have enough light to get away with the 1/4000 shutter speed your plate is now moving 1/16" in each frame.

 

The more acute you make the angle between the camera and the road the less the plate will move perpendicular to the frame.

 

My Camera is only 4m (15ft) from the gutter and my shutter speed is set to a max of 1/1000. I get clear captures day and night with a Sub $50 illuminator) I started out at 1/500 but still got motion blur. Cars in my street are doing 50 - 60km/h (30 - 40Mph)

 

 

 

viewtopic.php?f=19&t=44641 Read that thread too.

 

google some dedicated LP capture systems and see what kind of hardware and software they use. Some LPR systems have special software to deal with reflective plates and IR problems. The info you get may give you some ideas on lenses and frame rates.

 

Those dedicated LPR systems are usually beyond the budget of a home user. You don't need special equipment for human read capture. Standard home equipment set up correctly is fine. It has been done quite successfully with a Hikvision 2032 at night.

[komag 0]

buy this

http://www.aliexpress.com/item/DAHUA-2MP-12X-IR-Bullet-Camera-with-POE-Outdoor-1080P-Network-Camera-with-100m-IR-Distance/32242981781.html

[stroonzo 0]

Let me reiterate what was already described (but in a different way). FPS has nothing to do with capturing the plate clearly. Shutter is the important factor here. You will need a min shutter of 1/1000.

 

Your FPS should be set at a rate consistent with the number of shots in the scene (that you'd like to have) for which a car passes in an amount of time at a speed of travel.

 

Also, using a Hik NVR you will need to most likely go directly to the camera's IP address on that side of the NVR's firewall to access the web GUI to get to setting such as shutter and day night switch.

[MaxIcon 0]

buy this

http://www.aliexpress.com/item/DAHUA-2MP-12X-IR-Bullet-Camera-with-POE-Outdoor-1080P-Network-Camera-with-100m-IR-Distance/32242981781.html

 

61.2mm in a bullet cam! That's pretty impressive. I'm tempted to try one, despite having sworn off of Dahuas.

[thewireguys 3]

buy this

http://www.aliexpress.com/item/DAHUA-2MP-12X-IR-Bullet-Camera-with-POE-Outdoor-1080P-Network-Camera-with-100m-IR-Distance/32242981781.html

 

61.2mm in a bullet cam! That's pretty impressive. I'm tempted to try one, despite having sworn off of Dahuas.

 

Axis has a 4.7-84.6 mm bullet with built in IR.

 

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[Del Boy 0]

I have used a 6mm HFW4300S for numberplate recognition with no problems. In fact, the number plates are smaller than yours in my image. The key is tweaking the shutter speed.

 

Also have a PTZ with an auto-iris and zoom which has no problem catching number plates.

 

My other observation is I'm catching numberplates at less of an angle but have no problem with cars doing 40mph.

[MaxIcon 0]

buy this

http://www.aliexpress.com/item/DAHUA-2MP-12X-IR-Bullet-Camera-with-POE-Outdoor-1080P-Network-Camera-with-100m-IR-Distance/32242981781.html

 

61.2mm in a bullet cam! That's pretty impressive. I'm tempted to try one, despite having sworn off of Dahuas.

 

Axis has a 4.7-84.6 mm bullet with built in IR.

 

That looks even better, but is $1300 compared to $300 for the Dahua. That's outside my discretionary test-drive budget!

[Penhead 0]

Here is a capture of a guy throwing a beer can in my yard from a 2032 with the 25mm lens mentioned above from about 70-80 feet away. Just wish there was a face to go with the license plate and his (repeated) crime. This guy is the reason I modified a camera. Edit-25mm lens is the 1/3 version.

[MaxIcon 0]

That looks a lot like what I get with mine in the daytime, including the purple fringing. I've got a bit more angle and more distance, but the plates are very readable.

 

Your plate image is 100 pixels wide, which is a great size. The quality on mine goes away after dark, due to not having enough illumination. Your angle might give better IR reflection. How does it look at night?

[Penhead 0]

That looks a lot like what I get with mine in the daytime, including the purple fringing. I've got a bit more angle and more distance, but the plates are very readable.

 

Your plate image is 100 pixels wide, which is a great size. The quality on mine goes away after dark, due to not having enough illumination. Your angle might give better IR reflection. How does it look at night?

 

Night shots aren't too great, too much distance for IR. Did a lot of tweaks to image settings and couldn't find a sweet spot for plates where they were reliably readable.

[MaxIcon 0]

I got my best results with color mode due to a bit more contrast, but it's too dependent on the ambient lighting. If there's another car lighting up the plates, I can get a read, but even the license plate light on cars that have them isn't enough at the exposure times needed to cut the motion blur.

 

I suppose a high power IR blaster would do the trick, but I'm not ready to mount these on the front of my house!

[SyconsciousAu 0]

I got my best results with color mode due to a bit more contrast, but it's too dependent on the ambient lighting. If there's another car lighting up the plates, I can get a read, but even the license plate light on cars that have them isn't enough at the exposure times needed to cut the motion blur.

 

I suppose a high power IR blaster would do the trick, but I'm not ready to mount these on the front of my house!

 

They aren't exactly discreet are they?

 

Also Max where do you source your longer screws for mounting the 25mm lens?

[MaxIcon 0]

I have a bag of tiny screws from disassembling dead hard drives. I started doing this when I had to repair some Macs, which use lots of tiny screws in a variety of lengths, and I couldn't get them at the local hardware stores.

 

These are M1.0 screws, but I don't remember the length. I'm hoping to install another 25mm lens this weekend to get traffic from the other direction, and will check the length when I do this. They were only a mm or two longer than the original screws.