[Question]: Stationary car keeps alerting...

[Answer-1]

What is your question:

Using 0.14, a car is parked in the driveway and that driveway (yellow zone) is setup as a zone to alerts on car and persons. The thing is, I constantly get alerts of that car when somebody walks in the street or another car passes by.

So, I said hey, let's add an object mask there to prevent that detection

but upon doing that, only small parts of the car are now being detected and I'm still getting false alerts...

I can't really split the zone more than that to prevent false alerts.. Anything that could be done here? Wondering why only parts of the car are now getting detected after the object mask is added..

Thx!!

[NickM-27]

We need to see your config. the white box means the car is considered stationary so I don't think that car is being made part of the alert if things are setup correctly

[Answer-1]

Here's the config for that cam (Wyze v4):
(That config is me trying to split the initial object mask in two different zones)

  front:
    enabled: true
    mqtt:
      enabled: false
    ffmpeg:
      inputs:
        - path: rtsp://127.0.0.1:8554/front
          input_args: preset-rtsp-restream
          roles:
            - detect
            - record
    detect:
      width: 1280
      height: 720
      fps: 5
    zones:
      terrain:
        coordinates: 
          1,1,1,0.392,0.607,0.382,0.317,0.404,0.182,0.421,0.111,0.448,0.05,0.489,0,0.529,0,1
        objects:
          - person
          - car
        inertia: 3
      rue:
        coordinates: 
          0.276,0.265,0.422,0.226,0.708,0.173,1,0.184,1,0.331,0.643,0.324,0.346,0.35,0.132,0.398
        objects:
          - person
          - car
        inertia: 3
    motion:
      mask:
        - 1,0.931,1,1,0.711,1,0.711,0.931
        - 0,0.357,0.221,0.208,0.381,0.156,0.56,0.151,0.628,0.121,0.678,0.165,0.936,0.162,1,0.216,1,0.126,1,0,0,0
      threshold: 40
      contour_area: 10
      improve_contrast: 'true'
    objects:
      track:
        - person
        - car
      filters:
        car:
          mask:
            - 0.597,0.143,0.545,0.065,0.443,0.074,0.401,0.201
            - 0,0.406,0.001,0.298,0.079,0.271,0.09,0.335
            - 0.429,0.416,0.206,0.437,0.179,0.573,0.404,0.501
            - 0.144,0.642,0.326,0.615,0.351,0.745,0.136,0.751
    record:
      enabled: true
      retain:
        days: 5
        mode: motion
      events:
        retain:
          default: 10
          mode: active_objects
    snapshots:
      retain:
        default: 10
      required_zones:
        - terrain
        - rue
      enabled: true
      bounding_box: true
    review:
      alerts:
        required_zones: terrain  # Yellow zone in smapshots
      detections:
        required_zones: rue  # Blue zone in snapshots

Yeah, the car is actually marked as stationary so I thought it should be good, but it gets detected again when something goes by in the street and creates a false alert.

Here's another exemple when a truck was backing up in the street:

Only like parts of the stationary car are getting detected (after adding the object masks):

[NickM-27]

Right, the masks are not going to help here.

In general this appears to be a detection issue, the default model is not detecting the car well overall so when motion occurs due to a car driving by the box changes enough that the car is considered active.

I think you would benefit from perhaps increasing the contour_area for motion some more (perhaps to 20). If that does not solve this, then I have two other ideas:

If you are open to it, in my experience the Frigate+ models are much more accurate in general and especially with this type of scenario. My parked cars are much more stable with my Frigate+ model. That is however a paid solution.

Another idea would be to create 2 zones. Keep the yellow zone but make it only detect people (and whatever other objects you want except car). Create a new zone that only covers the entrance to the driveway (basically the part of the driveway that has no zone right now) and make it only detect car. Then put a car mask on the rest of the driveway. This should ensure that the car is detected when entering the driveway but is ignored once it is past that point. This is really not ideal, so only recommended as a last ditch effort

[Answer-1]

Ok, makes sense about the detection issue, so at least I'm not crazy! lol!

I'll try the contour_area tuning and report back,

I've been thinking about Frigate+ so this might be the needed edge case.

Thx!!

[Thorsten1982]

it now works by increasing the contour_area. I have a similar problem and keep getting alarms even though the car is stationary. I've already set the value for contour_area to 60 and I'm still getting alarms.

This is my config
motion:
threshold: 45
contour_area: 20
improve_contrast: 'true'
zones:
nebeneingang:
coordinates: 0.236,0.558,0.926,0.46,1,0.442,0.993,1,0.209,0.99
loitering_time: 0
inertia: 3
record: # <----- Enable recording
enabled: true
review:
alerts:
required_zones: nebeneingang
detections:
required_zones: nebeneingang
objects:

Optional: list of objects to track from labelmap.txt (default: shown below)

track:
- person
- dog
- car
- bicycle
version: 0.14`

[NickM-27]

What does "alarm" mean?

[Thorsten1982]

Oh sorry, I meant that I get a notification from Home Assistant on my phone.. I use the notification blueprint. And then I see that nothing happens in the video. But a detection is also displayed in the review window even though the car is just standing and not moving

[NickM-27]

if an alert is shown then the object was detected as having moved. If it didn't move then that likely means that the detection is not consistent enough so the bounding box varies quite a bit

[Thorsten1982]

Yes, I understand, and how can I change this? As I said, I've already tried increasing the threshold and contour area, but that didn't help.

[NickM-27]

If objects are not detected reliably you can either use a different model that is better at detection / tuned to your cameras, or you can use an object mask to block out the car when it is parked

[Answer-1]

Update for anyone who is interested, I mostly fixed my issue by a way I never thought about before...
That front camera is a Wyze V4, so running in 2K, and my issue wasn't really the zones setup, but "ghost" car detections or detections only for small parts of the car, when other stuff was moving around the stationary car.

Here's an exemple:

Tried a bunch of ideas and none worked.

I had detect resolution at 720p which I thought would be good for the cam, I was running that resolution with the previous V3 camera. Well, I tried commenting the lines in the config to make it run at native resolution, and boom, no more false detections.

I've been running all day and only 2 alerts, which were true ones. So basically, if you are having issues, use the debug view to see what is going on!!