License Plate Recognition at Night

[MTG 0]

Hi,

 

This is my first post on this form, I have the Trendnet TV-IP430PI, it is an outdoor 2MP 1080p PTZ camera. I purchased this for license plate recognition as my Dropcam's were not sufficient. It records license plate information during the day without an issue. However at night the license plate is over exposed. I am able to get around this by turning off the IR lights, however that prevents me from capturing anything else but the license plate. Is it possible to capture the license plate and the detail of the car? I attached some screenshots of what I captured and the different settings on the camera.

 

I appreciate your help!

 

Thank you

 

With IR ON:

With IR OFF:

 

Settings 1:

Settings 2:

Settings 3:

Settings 4:

[GCoco 0]

Try a shutter speed of 1/500 up to 1/1000. I have mine set so that with no other light but the IR you still capture the plate. However, you will lose vehicle detail, but if you have plate you got what you need.

[MTG 0]

Try a shutter speed of 1/500 up to 1/1000. I have mine set so that with no other light but the IR you still capture the plate. However, you will lose vehicle detail, but if you have plate you got what you need.

 

Thank you, adjusted the settings accordingly (1/725). Will let you know if the plates are visible when a car drives by, does it affect video quality during the day?

I attached screenshots of the current settings.

 

Current Settings:

[GCoco 0]

The video will tend to be darker.

[MTG 0]

It still seems to not capture license plates, any other settings recommend? It is a PTZ Camera so I can movie it around

 

[GCoco 0]

Your FOV is too wide/tall. You need enough pixels to read the numbers/letters. If I remember correctly you need the letters to be at least 15 pixels tall to read. There are plenty of FOV calculators out there.

 

Since LP numbers/letters are 2.5" tall (here in Louisiana) then you need approximately 75 pixels per vertical foot. A 2MP camera has 1920W x 1080H so your FOV can be no more than about 15 feet at the license plate location (1080/75). Obviously the greater the camera is from the car, the larger the lens needed.

 

For example a 2MP camera with 1/3 inch sensor and 60 feet from the car would need a lens with a minimum focal length of 20mm.

 

Also, make sure your IR will provide enough illumination without vehicle lights on or any other lights, that way someone trying to "sneak" in without lights, you can still read the LP.

 

I actually had to set my shutter/exposure to 1/1000 and the camera is dedicated to LP reading in that I have another camera covering the broader area but it cannot get the resolution needed to read the LP.

[freightrain 0]

Hello GCoco, what NVR/DVR and Camera combo do you have? I'm in the same situation where I have many cameras around my house but none can see License Plate at night. Thank you.

[rdot 0]

It still seems to not capture license plates, any other settings recommend? It is a PTZ Camera so I can movie it around

 

 

 

MTG I can only repeat what I have learned from doing my own research online: Which is that your License Plate Camera should be use for one thing, capturing license plates. Many people try to have that camera do multiple things (show details of something else). If you want that you should have another camera set up for that. just my .02.