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megavolt512

Why can't I read this license plate?

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See attached picture. This is broad daylight. Camera is a 480TVL Nuvico, going through a Nuvico NJVJ DVR.

 

While the images are fairly sharp, it's almost like there is this invisible shield over all license plates! As if they were blank. Is this a common problem? Do I need to spend the $$ on a special license plate camera even in broad daylight as is this?

Robert3.jpg.ea0339002825f541b23e156dd4a26696.jpg

Robert1.jpg.d4e87f5d15c3966374271577cf350446.jpg

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There are many things to think about here...

 

1) 480 TV Lines is not "High Resolution"

2) Nuvico is not the best for good video

3) The recorded video is being compressed

4) The license plate is maybe 5% at most of the entire picture, your gonna need it to be better than 60% to actively identify the plate.

5) This is not a license plate camera

 

Did you install this yourself or did somebody install this for you claiming it would read plates?

 

Your next step is to purchase a license plate recognition camera from Extreme CCTV.

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What he said, basically the camera has to be zoomed right in on the width of the vehicle .. plus the camera itself might not be the best .. there are other features that can be mentioned also ... and dont look at the TVL but look at the effective pixels .. what model camera is that?

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and dont look at the TVL but look at the effective pixels .. what model camera is that?

 

Model is a Nuvico HW3895IR36

 

Specs:

 

CCD Total Pixel: 811(H) x 508(V)

1/3" SONY SuperHAD CCD

480 TV Lines

3.8~9.5mm Vari-focal, DC Auto Iris Lens

Mechanical IR Cut Filter

 

I know I shouldn't expect too much from a low end system. But other details with less contrast than a plate seem to show up.

 

Any cameras in the <600.00 range that would do sustantiall better than this?

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To make this work, you need to zoom in quite closely. This means that you need a choke point for the cars, so the license plate will be in a predictable area.

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and dont look at the TVL but look at the effective pixels .. what model camera is that?

 

Model is a Nuvico HW3895IR36

 

Specs:

 

CCD Total Pixel: 811(H) x 508(V)

1/3" SONY SuperHAD CCD

480 TV Lines

3.8~9.5mm Vari-focal, DC Auto Iris Lens

Mechanical IR Cut Filter

 

I know I shouldn't expect too much from a low end system. But other details with less contrast than a plate seem to show up.

 

Any cameras in the <600.00 range that would do sustantiall better than this?

 

For a bullet camera, it has some good specs, and decent amount of pixels .. BUT, bullet cameras typically lack other features that full box cameras have, such as improved light and glare handling abilities. Basically you sacrifice features for size and ease of installation ...

 

If you really want to get a better image, no guarentee it will work much better, but need a box camera such as Ge, Pano, Bosch, Sanyo, etc, True Day Night with Mechanical IR Cut Filter, or better yet High Res B/W, zoomed in with a 5-50mm Day Night Lens .. still need to fit it on the width of the vehicle to really get the plate, and also look for a WDR camera for the glare aspect, plus night time is going to be hard either way you cut it, and thats why Secu Monster recomended the Extreme CCTV Reg Cameras which are designed for 24/7 Licence Plate Capture.

 

I should note, there are also some IP cameras that may help with this application, but you would need to ask about that in the IP forum

Edited by Guest

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Panasonic options...

 

1st Choice: WV-CW484S Dome

2nd Choice: WV-CF294 Dome

 

Its going to be hard to capture a plate without a license plate specific camera. I would say your chances are in the 6% range. You have too many things against you, including the DVR.

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Panasonic options...

 

1st Choice: WV-CW484S Dome

2nd Choice: WV-CF294 Dome

 

Its going to be hard to capture a plate without a license plate specific camera. I would say your chances are in the 6% range. You have too many things against you, including the DVR.

 

I was looking at the Samsung SHC-740 WDR as a possible replacement. What do folks thing of this camera, possibly set it up on a lower-end Geovision card. Focus it tightly on the driveway as sort of a dedicated cam?

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how about a phone cam aimed through binoculars for license plate capture

model xz1 specs 432.6 tvl with Sony chip

 

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your problem would be solved by a Number plate CAM for sure.[REGx etc]

 

The pictures you posted are high in gamma and need to be reduced a bit.

-contrast and brightness up too high -might be set for better night use?

the resolution of 712x480 pixel depth 16million is great.

>the plate data is only 29x11 pixels -not much! -you need optics

 

You cant read the Number plates or get any fine details because your images are being degraded by high compression -mpeg etc

 

You can solve this by using the whole image not 20% like you have.

I would aim a No plate cam\color overview at the choke point at the start of the court then you will get the cars in the same position each time and a nice full frame. -use a 10-50mm lens or so to get it right.

 

you still need a wide angle overveiw there also.

 

my 2c

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I can't believe the comments here....

 

The #1 reason why you can't get a plate is BAD ANGLE.

 

See if any of these dealers will issue a 100% refund on these mega expensive "LPR" cameras with a FOV like that. IT WILL NOT WORK.

 

 

You need to trap the vehicles and focus in on that area.

 

The camera that gets plates will be basically worthless for anything else.

 

 

EDIT:

 

Also your DVR has to suck, 1fps and .9fps??? For good plate identification you need to be able to burst some framerate.

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Example of a b&w decent res camera (vantage dsp mono), Fitted with a manual iris 25mm lens,test shot through a upstairs window viewing across a road, so a fair distance away. Plate is readable, but if was parked at the rear of the shot, it would no longer be readable, unless I used a bigger zoom, or higher quality cam. (dvr used visimetrics fastar)

 

plate partially blocked for privacy reasons.

lp.jpg.00a3a9d7acdf248e0bf561a75613b8aa.jpg

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do-it-yourself LPR is not easy to attain, especially if your depending on it for night use. the equipment/technology used needs to be correct before you even try to figure out the "target" area.

 

I've been down both roads.built one that worked ok, purchased one that works. I prefer to use the one that works but will build one that is ok. I allow my clients to make the decision, which is always financial decison.

 

- placement of the camera, camera angle, and target area, are all critical in improving license plate video collection. I've learned that you need to get "behing and slightly above the targeted area. this allows for the varying license plate mounting points on varying vehicle. and when the target drives away from the LPR camera the picture continues to capture more than just a plate. Any angle to the target will create more "speed" in capturing the plate.........that equals additional fps to ensure plate is inframe. less angle equals less speed and therefore reduces the failure factor.

 

- gates and gated communities all have pullover ares for vehicles, and sometime the drivers pull over to the gate while entering to talk to the guard. all this can cause the target area to be huge. I don't try to capture that large of an area, I move the camera back to the entrance and point it at the back of incoming traffic. this way I get behind the target and will always get the target. even if they enter on the wrong side the targe will appear in the camera. maybe a bit large than perfect but I will get it.

 

 

I installed 2 LPR's a few weeks ago and am reinstalling them in the proper location this Thursday. Had to wait for trenching to get done.......I post some LPR captured right after I installed and it worked, but after I relocate them the actual overall reliability is going to be much better.

 

Semper.........

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Orig.jpg

^^^^ This one is the only example that I see that truely needs an LPR cam to work right. The others might make it nice but could have been done without the extreme cctv boated costs.

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Orig.jpg

^^^^ This one is the only example that I see that truely needs an LPR cam to work right. The others might make it nice but could have been done without the extreme cctv boated costs.

 

24/7 operation .. they needed it, tried regular cameras and it wouldnt do 24/7 and they couldnt pay for our time .. remember its a business and time is money

 

Dos anyone truly have an app that only requires capturing plates during the day time?? Well perhaps if there is lighting 24/7, but ive never been so lucky to get those type of jobs

 

Ps. its all the same camera.

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I have had a REG camera up for about 6 months now. At first I was impressed, but the more I look at the video from it, the more I notice it misses a lot of plates. Could need to be moved closer to the road, but the whole reason I got it was because it was supposed to be able to read plates from the distance I mounted it at (90ft.)

 

I'd say it's hit or miss.

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Could need to be moved closer to the road, but the whole reason I got it was because it was supposed to be able to read plates from the distance I mounted it at (90ft.)

 

Extreme Reps always told me not to mount more than 80ft out...

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The guy I talked to said with the Lens I ordered, I'd be good up to 100ft. no problem.

 

I've also noticed that if the plate is either old or dirty, it is completely unreadable as well.

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well you can see the distance ours is mounted .. its right there.

Standard box cameras worked ok for the day, more miss than hit, but worked, but nightime they saw nothing.

 

PS. most plates here are dirty

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relocated the LPR's today into the proper locations...............they are working very well.......better angle, camera location is dark, and IR kicks in without any problem. will post pics tomorrow of tonight.

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tried to post it but I get a "check ftp settings" error..........I did not change anything on my PC so??????????? any hints?

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tried to post it but I get a "check ftp settings" error..........I did not change anything on my PC so??????????? any hints?

 

I have the same problem

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