False alarms due to reflections

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Tiamat1701
Posts: 55
Joined: 24 Nov 2016, 02:06

False alarms due to reflections

Post by Tiamat1701 » 07 Dec 2016, 04:12

I have Presence pointed at my driveway. I defined the detection zone around my driveway, and excluded the road at the end of my driveway. I've noticed that when it rains, Presence will detect the reflection of passing car's headlights on my driveway. Not the car itself - that is outside of the detection area. But their reflected lights off my driveway will trigger Presence to detect a "car"

Clearly it is not detecting a car ... at least it shouldn't as my detection zone does NOT include the road. This works fine when it is not raining. Passing cars then do not trigger an alarm.

I suppose false alarms are less severe than missed events. Still annoying to get alerts all night long from passing cars when it rains!

Badflex
Posts: 29
Joined: 11 Nov 2016, 19:17

Re: False alarms due to reflections

Post by Badflex » 07 Dec 2016, 09:28

It's the same with me

Una Real
Posts: 300
Joined: 04 Dec 2012, 23:16

Re: False alarms due to reflections

Post by Una Real » 07 Dec 2016, 09:58

Interesting to know. Understand your pain, but not sure these can logically be classified as "false" alarms. Think I'd actually be more concerned if these reflections were not triggering alerts. After all, expecting the algorithm to be sophisticated enough to distinguish between reflected headlights and an actual car in the alert zone is kind of like having a mirror positioned in an alert zone in such a way that it catches the image of a person outside the zone.

Just curious - if a person was carrying a flashlight in each hand would they be a person or a car? And what if one was staggering home from a furry party?

I do sense a real opportunity here for Netatmo to sell rain gauges. If it's raining, tell Presence to not send notifications about cars. Problem solved.

meboot
Posts: 29
Joined: 23 Nov 2016, 10:20

Re: False alarms due to reflections

Post by meboot » 07 Dec 2016, 22:52

Today is the first snowy day here, and within the last three hours, I had five false alarms :evil: The camera is located under the roof overhang and does not directly get in contact with the snow. However, I think the Presence has its problems with snow that the wind blasts sideways.

Tiamat1701
Posts: 55
Joined: 24 Nov 2016, 02:06

Re: False alarms due to reflections

Post by Tiamat1701 » 08 Dec 2016, 23:59

For sure, my Trendnet IP camera picks up blowing leaves, snow, heavy rain as movement and records an event. The Trendnet does allow one to set the sensitivity, detection area, etc, but it is plain dumb.

I expect motion detection to be dumb. But Netatmo's language is potentially misleading. Remember they advertise Presence on their own website as "Ultra-precise alerts let you know instantly about what happens outside your home. "They also advertise "RECORDS ONLY WHAT MATTERS - Presence records only when something happens, there are no hours of empty footage."

Tiamat1701
Posts: 55
Joined: 24 Nov 2016, 02:06

Re: False alarms due to reflections

Post by Tiamat1701 » 10 Dec 2016, 13:23

I also see false alarms when the lighting changes. For instance, if my car is parked in the driveway in view of the Presence, and the sun disappears behind a cloud, or comes out from a cloud. These lighting changes appear to the Presence as movement, and flags it as a "car was seen"

EssexBoyRacer
Posts: 21
Joined: 12 Dec 2016, 17:54

Re: False alarms due to reflections

Post by EssexBoyRacer » 12 Dec 2016, 18:05

I also get what I'd consider false alarms caused by reflections of traffic reflecting off the back window of a car on our drive.

I've tried the improve detection option for all the false alarms over the 2 days I've had it installed. It's better, but so far when it's dark and raining it goes off constantly.

I've worked around the issue for now by boxing out the back window of the car with multiple zones, but that's used up all the 4 possible zones and means I need to make sure the car is parked in the same spot every time.

I've participated in the product improvement plan in the hope Netatmo support will be able to use the data to improve the recognition algorithims.

kiboost
Posts: 587
Joined: 21 Jun 2013, 09:27

Re: False alarms due to reflections

Post by kiboost » 12 Dec 2016, 20:08

Same here, not many false alert, but this one caused by car lights reflections on a surface being into alert zone is redundant.
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meboot
Posts: 29
Joined: 23 Nov 2016, 10:20

Re: False alarms due to reflections

Post by meboot » 13 Dec 2016, 10:48

I recently observed that there are many false alarms during foggy and snow weather. My Presence had six false alarms last night from 10pm to 5am

Una Real
Posts: 300
Joined: 04 Dec 2012, 23:16

Re: False alarms due to reflections

Post by Una Real » 13 Dec 2016, 11:24

Was kind of expecting heavy snow might present a problem. However, last night we had a squall that put down a couple of inches in a short time and received no false alarms. Haven't experienced fog yet, but would think that's an especially tough one and not sure anything can really be done about that.

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