OpenALPR Missed This One ....

icpilot

Getting comfortable
Feb 1, 2018
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View attachment NLPR.20211130_180001_1.mp4

















If you go through it frame by frame, you can see only 2 or 3 frames get completely washed out, while the frames preceding those and following those are quite clear. This is a consistent theme with missed plates at night.

These are my Night-time cam (IPC-HFW5241E-Z12E) settings:

ALPR01.JPG

ALPR02.JPG

ALPR03.JPG

ALPR04.JPG


Any suggestions for settings changes to adjust for that center frame washout?
 
It happens. I have some very clean plates go by that OpenALPR completely misses, yet the rustiest dirty plate comes by I cannot manually read and it gets it.

But you did get that blinding white in the middle. I would probably take the iris down to 50 and HLC to 50 and bump up brightness to compensate if needed. I think the 100 iris is why it washed out.
 
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It happens. I have some very clean plates go by that OpenALPR completely misses, yet the rustiest dirty plate comes by I cannot manually read and it gets it.

But you did get that blinding white in the middle. I would probably take the iris down to 50 and HLC to 50 and bump up brightness to compensate if needed. I think the 100 iris is why it washed out.

Thanks, I'll give it a try. Tweaking the settings gets to be tough after a while because, as you point out, it captures some things which are unexpected and then misses things it seems like it should read.
 
Late at night I have a neighbor return home through my LPR camera, a Z12E. It misses her every time. From what I can tell, it is because her headlights sweep another camera I have, which is running DS. The spike in CPU seems to cause the issue. It is her timing in doing so that seems to cause the issue. I haven't found it happening on many other plates. Most that it misses are not visible when I look at them, paper, whatever. But it catches the vase majority.
 
if your CPU is struggling when that car goes by this might help Rekor Documentation

camera_buffer_size = 60

My CPU is an i9-9900k and seems solid at less than 15% while running GPU acceleration for both Rekor and Deepstack. I checked my settings and had it set for 30, but I bumped it up to 60 to see if that makes any difference.

Thanks for the tip.