OpenALPR and white screen at night?

wittaj

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Just had a recent issue pop up that isn't impacting the reading of the plates, but it is causing constant CPU fluctuations.

At night, my screen will alternative between the image being white and then black. No real pattern, but every time it happens, it is spiking the CPU. Also the FPS is fluctuating from what is set in the camera.

I tried a restart of the service and the camera. Adjusted the settings, and cannot seem to make it stop. It still seems to capture a plate, but it is causing high CPU all night.

Anyone experiencing this?

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Bitslizer

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not for open alpr but I had something similar when my poe nvr can't supply enough power to both the 4k and the ptz using a pft1300. The ptz would skip frame and go white or green screen when the IR draw more power than the nvr poe port can handle.
 

biggen

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That’s the video coming from the camera? Yeah that doesn’t look good does it.

You can see it doing it from BI?
 

wittaj

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The video feed in BI is fine and doesn't exhibit the same behavior which leads me to believe it is something with OpenALPR.

OpenALPR reads the plate fine, but every time it alternates between the black and white screen it thinks it is motion so it is analyzing it and then the CPU is spiking because it is very frequent - sometimes a couple times a second. Then it may go a second or two. My CPU is usually really low at night, so when I was watching it fluctuate greatly I started to try to figure out why and that is when I opened the OpenALPR and saw that happening.

I thought about the power but since it isn't exhibiting it in BI so I ruled it out. I will change the power from the POE+ switch to an injector and see if fixes it. It does only happen at night, so maybe that is the issue. Maybe it is fine for BI but OpenALPR is more sensitive to it?
 

biggen

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Very weird. And this just started happening? You haven't changed anything as far as OpenALPR goes or the camera settings/equipment?

I'm guilty of never logging into my OpenALPR/Rektor Dashboard since I run the OpenALPR webhook service and use that for all my viewing. Its been over two months since I logged into their dashboard so I'll have to login to the actual Rektor dashboard and see if I see any of what you are seeing.
 

mudflap5

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Just had a recent issue pop up that isn't impacting the reading of the plates, but it is causing constant CPU fluctuations.

At night, my screen will alternative between the image being white and then black. No real pattern, but every time it happens, it is spiking the CPU. Also the FPS is fluctuating from what is set in the camera.

I tried a restart of the service and the camera. Adjusted the settings, and cannot seem to make it stop. It still seems to capture a plate, but it is causing high CPU all night.

Anyone experiencing this?

View attachment 87066
Mine did the same thing, especially when there was a lot of motion in the frame, shadows, blowing leaves, etc. Seemed to happen more during daylight hours. By dropping the resolution down from 1920 x 1080 to 1280 x 1024, it very rarely does it anymore. Even with the lower resolution, it did not affect the accuracy.
 

wittaj

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Very weird. And this just started happening? You haven't changed anything as far as OpenALPR goes or the camera settings/equipment?

I'm guilty of never logging into my OpenALPR/Rektor Dashboard since I run the OpenALPR webhook service and use that for all my viewing. Its been over two months since I logged into their dashboard so I'll have to login to the actual Rektor dashboard and see if I see any of what you are seeing.
Yep, I use the utility as well so I am never in the Rektor Dashboard. But I noticed a few pics that was white and just assumed it was an anomaly.

Oh, I did do a cleanup recently of my cables, so maybe I have overloaded one of my switches with all IR cameras. Will have to check that out. Strange that everything else works, but we have all seen crazier things happen!

@mudflap5 - yeah I noticed that as well when I first set it up during the daytime, so I masked those areas and it stopped.
 

biggen

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Definitely check your cables if it just started happening around the same time you did a cleanup. I don't even have a good guess as to what is going on. I use to get some pixilation in the OpenALPR snapshots occasionally and it appeared to come from when I had my I Frames set as the same as my FPS. When I went back to the Dahua default (double I Frame of the fps) that pixilation went away and I never saw it again.

They used to have a "Contact us" chat box on the bottom right hand side of their Dashboard after you log in. You could search for common questions and if those didn't answer your issue, you could actually open a ticket. I don't even see that anymore. How the heck are you supposed to contact them anymore?
 
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wittaj

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So to close this up, it was indeed the cleanup of my cables and when I reconnected my cameras to the switches, I had one too many cams with IR on at night on one of the switches.

Another story we have to tell when someone is experiencing an issue with a camera that we can point to regarding power. For everything else - BI, camera GUI - the switch was working perfect (or appeared to be), but was sending current right at the cusp of the tolerance threshold and was causing OpenALPR issues.

Glad I got that figured out and that it wasn't a camera going bad!
 

Bitslizer

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Do I win a prize? :D

Seriously glad to be able to help after all the advice I got from here.

Funny thing, I got a POE combiner and splitter to use instead of the PFT1300. plugging into the POE NVR and the POE NVR still cant provide enough power to the PTZ Mini speed dome. NVR is a speco speco n16nxp 4ks2 POE NVR for reference

 
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