Question on OpenALPR Upload Time

[Wildcat_1]

Quick question

Successfully setup OpenALPR on Docker with a 5231-Z12. Captured a tag right off the bat no worries. Since then however there have been 4-5 cars pass by, none have shown up in OpenALPR dashboard. Therefore had a couple of questions I was hoping the community could help with:

1) Is there some kind of buffer between event and appearing in the dashboard ?
2) Even if a plate cannot be read shouldn't something show in the log or dashboard ?
3) If I want to use sub stream 2 do I use the command 'channel=1&subtype=2' ?
4) What determines FPS as the OpenALPR is showing about 6FPS but the sub stream is set for higher ?

Thanks

 

[wtimothyholman]

It sounds to me that the OpenALPR agent can't keep up with the frame rate. The agent is dropping frames and consequently it's missing capturing some plates. The agent should be able to process frames at the same rate as the substream of the camera. I'll bet that the OpenALPR web interface constantly shows 100% CPU usage with the agent.

This isn't surprising, as the Docker container will have considerable processing overhead. There are some things you can do that might help, e.g. increasing the frame buffer queue setting for the agent. But ultimately the only solution may be a faster computer, and running the agent in Windows or Ubuntu.

 

[Wildcat_1]

It sounds to me that the OpenALPR agent can't keep up with the frame rate. The agent is dropping frames and consequently it's missing capturing some plates. The agent should be able to process frames at the same rate as the substream of the camera. I'll bet that the OpenALPR web interface constantly shows 100% CPU usage with the agent.

This isn't surprising, as the Docker container will have considerable processing overhead. There are some things you can do that might help, e.g. increasing the frame buffer queue setting for the agent. But ultimately the only solution may be a faster computer, and running the agent in Windows or Ubuntu.

T

Thanks for the reply @wtimothyholman . Yes having worked with Docker before its a little bit of a hog Not as much as the OpenALPR piece though. Tweaked things a little and now have the FPS on the ALPR agent matching the sub stream (20 fps) which is good.

One thing I have noticed since enabling the OpenALPR and pointing it to my 5231-Z12 sub stream is that there are a lot more disconnects when connecting to the camera from 2 instances (say web guide & OpenALPR capture processing at the same time). Not sure if others have seen this but have been able to repeat this consistently today. Wait for a car or cars to pass the cam, watch the latency increase a little on the network connect for the Z12 (monitoring across infrastructure), watch OpenALPR process and if you happen to be in the web guide of the cam at the same time, maybe updating the Main Stream, at least 70% + of the time it would kill the connect to the camera, lose IP etc for about 30 seconds to 1 minute before finally reconnecting. Will do some more digging on this but thought it was interesting (and not in a good way of course).

Thanks to the help in this sub-forum, getting some amazon day and good (getting better) night plate captures.