HDW5231R-ZE settings for LPR

Though some will disagree, and I'm simply an enthusiast not a Pro, I like CBR for tag cameras because VBR doesnt seem to react as quickly when youre talking about 6-8 frames of a passing car in about 1/3 second. I also like to match frame rate and iframe interval
 
Though some will disagree, I am a pro not simply an enthusiast... juz kidding
The most important setting is the maximum bit rate.
Constant bit rate does not make sense becos video encoding is basically using the difference between frames
hence if there is no motion and the scene is completely still the bitrate is theorectically zero. Not sure how to force a constant
bit rate out of a still scene.
 
:D
 
Y'all suggest I get another exact cam to test different settings on the same live subject ? ;)

I had a defocus issue today, while the cam was in color mode. Earlier captures in focus, later captures out of focus -- both daytime. No clues in the log.
 
Slightly better with 8mbps -- nice. Matched iframe to fps, but lowered to 16, since the IVS seemed to have higher false negative rate at high fps(?) I'm imagining that the cpu is too busy (but can't check the cpu usage log with the restricted shell commands). Images for ~25mph vehicle 20' from camera at max zoom.

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Not bad, you may be dealing with a tough angle as well...? Still some motion blur, You say trying 1/1000 didnt allow you to see the IR reflection from the plate?
 
This camera isnt designated as an LPR camera.

By and large other than those that have built in software to recognize and record plates, any good camera within reason can perform LPR duties if all you want to do is be able to capture them. As long as you have enough zoom, IR, and access to exposure settings, good angle, and plenty of patience, it can be done. Its part art part science ;)
There are plenty of old analog cameras out there that have been doing it for years.
 
@bigredfish the shots were noisy, but in retrospect, possibly this was due to high gain. Also I was calculating that at 25mph for a plate traveling at 20 degrees off the optical axis, that the plate movement would be 8 mm in 1/500 s, which seemed small. But this is actually fairly large relative to the plate letters. So it turns out that 1/1000 s is better (yes, I should have just paid attention, but I'm working on it). Still can't get that pesky motorcycle plate at dusk -- but probably going faster than 25mph. Images at daytime truck, dusk truck, dusk motorcycle.
 

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Increased fps/iframe from 24/24 to 30/30 (and shutter speed to 1/2000 :) ). May have to figure out how to move camera even closer to the street to reduce effective plate speed further.
 
Thanks @richardgohth . IMHO the car plate looks about the same with the gain range 10-25 (vs 10-30 previously). Will have to wait for motorcycle. Where may I read about gain affecting rolling shutter effect? I was guessing lower iframe relative to fps would approach global shutter behavior. In my case, moving camera closer to curb reduces the angle, but also exposes camera to construction trucks.
 

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Lookin pretty good!
 
@bigredfish do you feel that IR light significantly helps instead of the on board IR? Does off angle IR help a lot? Wondering if it will make a big difference on dirty plates.

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Yes, Ive found the more IR the better. At 120ft I use this mounted on top of the pole above the camera along with the camera IR.
Tendelux BI18

Both IR's in this case point directly at the tag capture area. I cant think offset would help with such a small area being focused on...?
 
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Gotcha. I might pick one up price isn't bad. I've also just thought about flooding the area with visible light and keeping the cameras in color mode no IR. I have problems with too many plates illegible due to being dirty.

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And I see a few with some kind of anti-reflective coating as well....white light and keeping in color is an attractive option if you have a situation where you can get away with it. Id' probably blind drivers and end up with a lawsuit :(
 
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