I'm using Plate Recognizer and the image it's reviewing needs to be delayed a second or two before it is captured and sent for review. Is there a way to control that?
How to control when the Alert image is captured from a camera
- Thread starter 105437
- Start date
sebastiantombs
Known around here
Look at the "pre-trigger" time in "Recording" settings for the camera and the "break time" in the motion settings for the camera.
Thanks for the reply. I changed the pre-trigger from 5 seconds to 4 and it didn't change anything.
This isn't a pre-trigger issue - it is a timing issue of the alert image. I use Plate Recognizer and have tested all the variables to get accurate results.
Mine are set at 0seconds pre and 0seconds post so that I get an image for each vehicle that comes thru. If I make it 5 seconds, then two cars could come through and the second one is missed. I do also record 24/7 in the event someone is one someones bumper lol.
A couple of things you probably need to do.
You probably need to change the make time so that it times it correctly and probably adjust your zones in BI. Depending on the angle you have, you may need to set the make time to like 0.3 or 0.5 seconds.
I would try just one zone crossing and not the whole screen - Here is mine where I have a zone drawn such that cars going right to left I get the front plate, and the cars going left to right I get the back plate. You can see in my alert images that the vehicles are all centered in the frame doing this approach.
And surprisingly, a higher FPS can result in it being missed (go figure). I have tested these variables tremendously getting mine to accurately get the vehicles. Mine is at 12 FPS. At 15 FPS it would miss vehicles.
It is some trial and error - post some screen shots and I can help you figure it out or I can TeamViewer in and help you.
Mine are set at 0seconds pre and 0seconds post so that I get an image for each vehicle that comes thru. If I make it 5 seconds, then two cars could come through and the second one is missed. I do also record 24/7 in the event someone is one someones bumper lol.
A couple of things you probably need to do.
You probably need to change the make time so that it times it correctly and probably adjust your zones in BI. Depending on the angle you have, you may need to set the make time to like 0.3 or 0.5 seconds.
I would try just one zone crossing and not the whole screen - Here is mine where I have a zone drawn such that cars going right to left I get the front plate, and the cars going left to right I get the back plate. You can see in my alert images that the vehicles are all centered in the frame doing this approach.
And surprisingly, a higher FPS can result in it being missed (go figure). I have tested these variables tremendously getting mine to accurately get the vehicles. Mine is at 12 FPS. At 15 FPS it would miss vehicles.
It is some trial and error - post some screen shots and I can help you figure it out or I can TeamViewer in and help you.
This isn't a pre-trigger issue - it is a timing issue of the alert image. I use Plate Recognizer and have tested all the variables to get accurate results.
Mine are set at 0seconds pre and 0seconds post so that I get an image for each vehicle that comes thru. If I make it 5 seconds, then two cars could come through and the second one is missed. I do also record 24/7 in the event someone is one someones bumper lol.
A couple of things you probably need to do.
You probably need to change the make time so that it times it correctly and probably adjust your zones in BI. Depending on the angle you have, you may need to set the make time to like 0.3 or 0.5 seconds.
I would try just one zone crossing and not the whole screen - Here is mine where I have a zone drawn such that cars going right to left I get the front plate, and the cars going left to right I get the back plate. You can see in my alert images that the vehicles are all centered in the frame doing this approach.
And surprisingly, a higher FPS can result in it being missed (go figure). I have tested these variables tremendously getting mine to accurately get the vehicles. Mine is at 12 FPS. At 15 FPS it would miss vehicles.
It is some trial and error - post some screen shots and I can help you figure it out or I can TeamViewer in and help you.
Thanks for taking the time to reply with all of that helpful information. I'm going to play around with the make time setting and see if I can see some changes.
I've been able to adjust the make time in order to get the alert image in the correct place. Now, the problem is the alert image is too blurry and I'm wondering if it grabs it from the sub stream.
Yeah, depending on your version, an older version couldn't pull a mainstream image, but it can now.
In my instance, since the car is in and out of the image so quick, I only use the mainstream with no substream for that one camera.
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I'm running the most recent version and I would prefer to leave the sub-stream for that camera configured. I'll ask Ken about this and see if he would consider a way to use the hi-res stream to grab the alert image.
As I mentioned, it is there with newer versions already.
Within the trigger tab under the camera settings, go to the When Triggered location and under the "Add to Alerts list" select the high-res jpeg option.
The issue is, depending on your field of view, you may find that this results in the vehicle being missed because it has to pull from the mainstream on the next full frame after the substream triggers motion, which is why I am just using the mainstream for that particular camera. It isn't usually an issue with any other camera field of view, but with LPR and the tight field of view we operate it under and how quickly a car can be in and out of the frame, it can be problematic.
I have found for my field of view and zoom that it is best to just run the mainstream for that camera.
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Cool, let us know if you get the plate in the frame still without having to make more modifications to your settings. I have less than ideal angles so it made a big difference negatively if I tried to use the substream. I could probably have played with it more but I had the camera set-up long before the substream option came to be, so I didn't want to mess with that and the CPU savings for one camera wasn't worth the risk of missing a car.
My angle and time the vehicle is in the frame is so short that when I made a clone camera just to test Plate Recognizer, the clone camera image was a half-car off of the clone master.