IVS false positives

ridlees

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Hi,

I am having issues with false positives with IVS on my IPC-HDW5541H-AS-PV. I have one active rule with the following settings:

Udklip.PNG

I have tried setting the sensitivity for "Smart Motion Detection" to both low, medium and high and I get false positives on all sensitivity levels.

Here are a couple of examples of the false positives.

Triggered by a bird:
View attachment 2020_11_06_08_56_52.mp4
























Triggered by nothing:
View attachment 2020_11_05_10_15_47.mp4
























Any ideas to how I can eliminate these false positives?
 

bigredfish

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You say IVS and then you say you've messed with SMD settings? They are two different things that have no relationship.

Turn off SMD and rely on IVS like the rule in the picture.
Set a minimum size box. try 300x300 pixels or so
Use a zig zag tripwire line covering the area, not an Intrusion box. That box you have drawn wont see "Cross" events very well and Ive found "Appears" doesnt work so well

IVS-zigzag.jpg

See this post
Dahua IPC-HDW5442T-ZE 4MP Varifocal Turret - Night Perfomance testing
 

ridlees

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Thanks a lot! I for sure thought that the sensitivity setting of SMD affected the IVS object filter. Good read on the zig zag tripwire! Totally makes sense why this should be more robust. Now the next days will reveal if this removes the false positives.
 

Shockwave199

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You will get false positives. Maybe less, but you'll get them. You can only dial it so much and you need to be certain you're not missing people and/or cars. Also uncheck 'appears'. Try just crossing. And trips are good fail safes in addition to intrusion but generally I do have better results with intrusion.
 

bigredfish

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Agree
Sure, try both lines as well as boxes. I do use boxes as well on my drive, but with a line backup. I do get slightly better detection with boxes (if drawn correctly) but more false alerts with them.
 

catcamstar

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With ^^ --> you do not have a "min" target box defined. Start with that. Secondly, your left vertical IVS line seems to give the impression it can "look behind" the corner. It can't. so if you would hide behind that wall, it would notice you "little too late". I would either draw a zigzag, or like @bigredfish wrote, work with intrusion box (ticking appear and disappear).

In any case: remember to TEST these IVS'es yourself: do this during the day AND during the night (as IR light might make target boxes larger than anticipated). The best way to test IVS is to have smartpss open on your laptop, and walk by your camera's: SmartPSS shows, in green, the "objects" of interest. This will indicate the maximum size (to not be triggered by shadow) and minimum size (eg a cat/bird).

Good luck!
CC
 

Shockwave199

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With ^^ --> you do not have a "min" target box defined. Start with that. Secondly, your left vertical IVS line seems to give the impression it can "look behind" the corner. It can't. so if you would hide behind that wall, it would notice you "little too late". I would either draw a zigzag, or like @bigredfish wrote, work with intrusion box (ticking appear and disappear).

In any case: remember to TEST these IVS'es yourself: do this during the day AND during the night (as IR light might make target boxes larger than anticipated). The best way to test IVS is to have smartpss open on your laptop, and walk by your camera's: SmartPSS shows, in green, the "objects" of interest. This will indicate the maximum size (to not be triggered by shadow) and minimum size (eg a cat/bird).

Good luck!
CC
Web interface shows that as well. I really don't care for pss. Exteriors can be difficult to dial in. Best advice I've followed thus far is to think of zones and lines as 3D, as opposed to 2D. And really in the ops scene there I'd recommend multiple trip wire and not intrusion boxes. The intrusion box he has drawn is not good for that scene.
 
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