Slow Triggers?

J

Janhaus

n3wb
Dec 2, 2019
27
9
Southeast
Re-tweaking BlueIris after my initial setup, I'm finding that there's a number of missed triggers, i.e. a car drives by but I don't get an alert. I set up motion zones based on some thread suggestions, but not sure if I'm doing it right - thoughts?
I live in a cul-de-sac, all rear plates are from cars going from right to left of the images.
Camera: IPC-HFW5241E-Z12E
Daytime shutter speed: 1/4000

Am I zoomed in too much? Do I need to adjust the zones so they're closer together or wider apart?
I'm processing 10 pretrigger and 10 posttrigger images, 50ms each - should I be processing more pretrigger? Spacing out the milliseconds more?
I would like the triggers to occur 'earlier', I think the issue when I watch the cancelled alert videos is that there's only a few frames of a car leaving, and the plate is nowhere close to the center of the screen...

The very first frame of my cancelled alert:
1746373811862.png

Screenshots of my settings:
1746373979876.png

1746373754791.png
1746373760271.png
 

Attachments

  • 1746373746253.png
    1746373746253.png
    1.4 MB · Views: 0
So that definitely helped, but I'm still missing some obvious plates.
See this .dat log:
The very first frame already has the car leaving, without any chance of getting a look at the plate.

However, the video captures the car in motion.
I had pretrigger record time and pretrigger playback time anywhere from 1s to 0.2s, don't remember what the setting was at the time of this particular alert, it was probably 1s.

It seems my issue is that the trigger occurs and there's a bit of a delay before the very first frame gets sent for AI processing. Questions:
Should I move my zones closer to the right side of the screen so they can trigger 'earlier' (for cars going right to left leaving the cul-de-sac)?
Does the pretrigger record/playback time factor into this?
I looked at my plate capture sizes and it's around 72ppf from using MS paint. I 'can' zoom in more on my Dahua cam, but won't this risk more non-captured plates?

1746450804416.png
1746450777106.png
 
Update: I went to full zoom, resulting in ~162ppf for license plates and changed FPS to 15 from 30. Also changed pretrigger to 0.5s, pre & post trigger analysis to 10 images, and motion sensor for just one zone (B) which is a vertical strip of ~8 blocks. Now I'm picking up almost all plates in the daytime, but I am getting a lot of cancelled alerts as well due to random motion.

Now to figure out what I can do for night-time, where I'm picking up only 1 or 2 plates at night. Maybe I need to clone the camera so I can have different trigger settings there? Not sure if this would work.

1746639488526.jpeg
 
That is correct - Make like Profile 1 (green) the day settings and Profile 2 the night settings and then you can set different size zones and make times and all that stuff for night.

For example, since my image at night is all black except for the head/tail lights and plates, I have the min size the size of a plate and the make time 0. I have the crossing zone larger as well.
 
Can you share your night settings or point me to a post if you already shared it elsewhere? I saw some people mention that for nighttime maybe not use zones at all, I can definitely try to widen my existing zone and see if that works. My image at night is also all black except for plates and lights, will tweak it tomorrow evening and see.
 
You must log in or register to reply here.
Top Bottom