Troubleshooting LPR

blazin912

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In this thread you were told to run fixed gain??

You may just have to run full color in the day and B/W at night which is pretty "normal" I'd say. We just have to figure out why your B/W at night is bad.
Yea this thread haha.. Yea I'm just trying to do my testing in the day in B/W as it's easier for me, my initial test showed that license plates are totally blank in the day when B/W mode is on.

Ideally I wan to run color day, b/w night.

I'm just getting totally bonkers night results and I don't have a ton of night traffic to dial it in.
 

biggen

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Yea this thread haha.. Yea I'm just trying to do my testing in the day in B/W as it's easier for me, my initial test showed that license plates are totally blank in the day when B/W mode is on.

Ideally I wan to run color day, b/w night.

I'm just getting totally bonkers night results and I don't have a ton of night traffic to dial it in.
I do see where he said that on page 1. I wonder if that is a typo or if he runs it fixed like that as well then.

I would say your color during the day is pretty well dialed in from the above shot. Tonight you just need to drive you car up and down the street a few times while dialing in the B/W mode.
 

blazin912

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I do see where he said that on page 1. I wonder if that is a typo or if he runs it fixed like that as well then.
Yep I asked if it was a typo and he explained it was to limit the auto-ranging to provide more consistent results.
 

IReallyLikePizza2

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Just take the plate off your car and have your wife run up and down the street, or just prop it up in shot
 

wittaj

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Yep, it was me saying no variable on the gain. At least in my situation, the camera couldn't adjust fast enough because the car is in the frame less than a second and it just washed out the plate because the camera couldn't decide what to do fast enough. Made gain the same and problem solved.

But as we have seen, every location and setting is different.
 

biggen

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Yep that's the plan tonight. Going to rig something up to hold it and see what happens
Here is what I would do:
  • Set your focus to manual for daytime, find the focus point/numbers, and set it
  • Leave the camera in color mode for daytime 24x7 as you look pretty dialed in there
  • At night, park a car at the point in the road you need, go to nighttime B/W, and set your focus to manual as you did for daytime (that gives you perfect focus for night and daytime now)
  • Then dial in your nighttime B/W settings with the car parked
 

Flintstone61

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it won't go out of focus due to switching if you leave it in night mode.
an overview cam can catch the color and make etc.....
 

biggen

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it won't go out of focus due to switching if you leave it in night mode.
an overview cam can catch the color and make etc.....
He isn't getting plates in B/W during the day. That is the issue.
 

blazin912

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^^^ Yea that's what I was trying to do but like was said B/W + MA plates + daylight = FUBAR
 

blazin912

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PROGRESS!!! @wittaj @biggen @IReallyLikePizza2




HLC is Off, IR is 100%

Plate Recognizer got an 88% read on that plate. Should I add in HLC? I had to do a lot of fiddling on my plate, parked and headlights off, to get the plate pretty well exposed ie dark text on white background. My main knobs were - Gain, Iris, Contrast, and Gamma. I lowered sharpness as it didn't seem needed and higher values were causing random pattern noise when I was parked so figured it would only be worse with motion, I lowered noise reduction a bit but was sort of guessing as I did the tweaking with a stationary plate. I also didn't really see a difference with varied Exposure Compensation, so even though I dialed that down it doesn't seem like a big deal. I will say looking at my video footage the road is now lit up by the car's headlights a bit. Seems like I could adjust to reduce that but I'm not sure how I keep the plate bright at the same time.. is this where HLC comes into play?
 

wittaj

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Great!

HLC at 50 should knock the headlights down.

Yea I run sharpness down around 4.
 
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Sorry I could not answer sooner. Was gone from home for a few weeks and some places had limited internet.

Check out my post on LPR. This one shows how I built the box and everything else:


Here are my current settings. You can get an idea of each setting and adjust to suit your needs.

LPR-E Day Settings 1-5-21.JPGLPR-E Night Settings 1-5-21.JPGLPR-W Day Settings 1-5-21.JPGLPR-W Night Settings 1-9-21.JPG

I am using the day/night utility. I keep the focus the same day and night, set on manual.
 
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