Need recommendation setting for Dahua LPR (DHI-ITC413-PW4D-Z1)

[myf]

Hi everyone, I'm relatively new to working with License Plate Recognition (LPR) systems.

Over the past month, I've been facing a recurring issue where the LPR camera misreads license plate numbers, both during the day and at night. I would greatly appreciate any recommendations for optimal LPR settings, especially for use in parking lots.

Here's my current setting

Thank you

 

[bigredfish]

I don’t have that camera. I use relatively cheap 5241 Z12s for LPR. Manually looking at plates of interest

That said, I see 3 things that drew my attention

1- DNR is way higher than I use, l run 25 day and maybe 35 night . DNR creates motion blur
2– I would never use WDR on an LPR cam, especially at night. Again motion blur is a result.
3- the slowest shutter I run for LPR is 1/1000

I also recommend CBR, high bitrate and 30 FPs

 

[myf]

I don’t have that camera. I use relatively cheap 5241 Z12s for LPR. Manually looking at plates of interest

That said, I see 3 things that drew my attention

1- DNR is way higher than I use, l run 25 day and maybe 35 night . DNR creates motion blur
2– I would never use WDR on an LPR cam, especially at night. Again motion blur is a result.
3- the slowest shutter I run for LPR is 1/1000

I also recommend CBR, high bitrate and 30 FPs

Ok thank you, will try this options

 

[bigredfish]

It looks like you're trying to capture both Overview and ANPR, with one camera, using color at night.

A noble goal!

But most learn its not practical. Two cameras, one doing ANPR with settings focused JUST on the plate (possibly in B&W/IR), and another, in color if you wish and have enough light, for Overview to capture details about the vehicle, is a safer bet.

 

[wittaj]

+1 above to everything @bigredfish said.

It is really difficult to get plates in color.

Agree to go with more zoom and recognize at night this probably isn't an overview camera also. It is designed for plates and that is primary purpose.

I would also go with a fixed shutter instead of the range. In some instances the focus tries to adjust due to the shutter changing due to available light and then you miss the plate.

 

[myf]

It looks like you're trying to capture both Overview and ANPR, with one camera, using color at night.

A noble goal!

But most learn its not practical. Two cameras, one doing ANPR with settings focused JUST on the plate (possibly in B&W/IR), and another, in color if you wish and have enough light, for Overview to capture details about the vehicle, is a safer bet.

View attachment 207419View attachment 207420

View attachment 207421

For now, we're using just one camera to capture both the overview and license plate numbers. Based on this, would a B/W (Black & White) or IR (Infrared) camera be optimal for LPR?

Also, here are my stream settings: I can only get 25 FPS. Is that sufficient for accurate LPR performance?

 

[wittaj]

This is a great camera to capture LPR, just recognize that whatever camera you use, if the primary goal is for plates, then expect at night that this will be all you see. If you get anything else it is a bonus. The camera you have can do infrared as well.

25FPS is fine. I would bump your bitrate to 8192.

Shutter speed is what captures plates, not FPS.

I capture plates at 8FPS.

 

[bigredfish]

Ok thank you, will try this options

Not saying its not possible, but to do what your attempting requires everything to be perfect, all of the time. Ambient light, vehicle speed, weather, etc.

With two cameras I can focus each on a specific task

Here's an example at distances closer to yours

For now, we're using just one camera to capture both the overview and license plate numbers. Based on this, would a B/W (Black & White) or IR (Infrared) camera be optimal for LPR?

Also, here are my stream settings: I can only get 25 FPS. Is that sufficient for accurate LPR performance?

25 is fine
At night unless you have a LOT of ambient light, yes IR will be better. Distance matters though

FPS for LPR to me is a matter of vehicle speed. The slower the vehicle, the less frames you need. Its nice having many frames to choose from. You'd be surprised how many fames/how much distance, a car traveling 40mph can cover

 

[myf]

Thanks, I'll try that option @bigredfish and @wittaj

 

[bigredfish]

One note, I lied about 1/1000 being my min.. That LPR shot is actually running 1/500. I can get away with that because 1) the camera is very close to the vehicle, and 2) the vehicle has to slow to 5mph to make the corner. Speed matters

 

[myf]

One note, I lied about 1/1000 being my min.. That LPR shot is actually running 1/500. I can get away with that because 1) the camera is very close to the vehicle, and 2) the vehicle has to slow to 5mph to make the corner. Speed matters

View attachment 207425

in my location there's speed bump (still not sure is effective or nope), but with that condition 1/1000 should be ok?

 

[wittaj]

1/1000 should be fine.

 

[bigredfish]

in my location there's speed bump (still not sure is effective or nope), but with that condition 1/1000 should be ok?

Yep, Im just saying if you have a lot of light and slow enough targets, you can get by with less. You'll have to experinment

 

[myf]

May i know how to reduce the white noises? i already reduce my sharpness from 70 to 60,

 

[bigredfish]

I rarely run sharpness over 40 but I’m running B&W/IR. When using color at night I never ever go over 50

There’s no one answer. Try increasing gain, and if you have a separate Iris control try adjusting it.

You’re suffering from not enough light in that image

 

[myf]

I rarely run sharpness over 40 but I’m running B&W/IR. When using color at night I never ever go over 50

There’s no one answer. Try increasing gain, and if you have a separate Iris control try adjusting it.

You’re suffering from not enough light in that image

Alright will try that, cause i am still need approval regarding the BW one

 

[bigredfish]

I’d work on approval of a 2nd camera

 

[myf]

anyway, is there anyone have facing this issue, my camera suddenly disconnected when storing image to ftp server? i have two camera (entry, and exit) both using the same ftp setting, but on exit camera i always facing this issue