Understanding Dahua motion detection with SMD

[Perimeter]

I am starting this thread because I still try to understand how motion detection works on Dahua cameras in combination with SMD. This is not about IVS rules, even if they work better.

I think I understand basic motion detection on dahua cameras, using zones, sensitivity and threshold. I understand the live diagram beneath. Some details are still unclear (like: do zone activations add up in the diagram?) but most of it is clear, so this is not an issue.

Things get foggy the moment I enable SMD: I would expect to only get clips when I see a person or a car on it. But I still get clips where the wind creates motion that is recorded.
So what would I have to do if I want to record only if the camera detects something it considers human or car? Set motion detection sensitivity to zero and human sensitivity to high?

From the description, I start to get the impression this is about alarms, not recordings.

 

[paul@austins.tv]

Sorry Perimeter. I'm foggy as well to your message.
What's the "live diagram beneath" please.

 

[Perimeter]

Sorry Perimeter. I'm foggy as well to your message.
What's the "live diagram beneath" please.

Settings - Event - video detection - motion detection - area settings:

This diagram visualizes your detection settings live and helps you understand what it takes to trigger.

(Side comment: It would be great if one could get this page during playback, so one could fine tune the settings. But I don't think there is a way.)

 

[paul@austins.tv]

Oh you make sense now. Indeed the graph not on playback! Perhaps a human friend can walk the motion detection field to fine tune the settings for you?

 

[Perimeter]

That part is not the problem. Understanding the effect of SMD is.

 

[paul@austins.tv]

Sorry I'm foggy again.
You state: "It would be great if one could get this page during playback, so one could fine tune the settings. But I don't think there is a way." Then you state: "That part is not the problem".
Sorry but you seem to be asking a question in a convoluted way, then expecting a basic answer.
Perhaps someone else can assist, as I'm giving up. Sorry.

 

[bigredfish]

I’ve not had much luck with SMD

As far as regular MD, my understanding is it simply reacts to a change in color/contrast of pixels within the box. Very basic and has been around forever. As we all know it’s too apt to false alerts. Sensitivity and threshold help but still basing itself on changes in a pixel and a percentage of affected pixels within the square.

SMD in theory overlays MD with AI and further tries to detect a human or vehicle. I’m not clear either on the relationship and how it actually works.

I know it (SMD) encompasses the entire scene and does not restrict itself to the regular MD detection area you specify.

According to Dahua
When a Dahua SMD camera is paired with an SMD enabled recorder, advanced algorithms are used to differentiate and send an alarm when human and vehicular shapes are detected. False alerts are filtered for up to 95% accuracy, saving customers the hassle of unwanted alarms.

 

[Perimeter]

According to Dahua
When a Dahua SMD camera is paired with an SMD enabled recorder, advanced algorithms are used to differentiate and send an alarm when human and vehicular shapes are detected. False alerts are filtered for up to 95% accuracy, saving customers the hassle of unwanted alarms.

Sounds as if I am right suspecting that it is about alarms, not recordings. I had hoped to cut recordings down.

I just made a simple test: I reduced sensitivity of the only active motion detection region to zero. Then I walked through the fov. And yes, I got recorded.
So setting motion sensitivity to zero and turning SMD on, seems to do the trick. I have to try this for a while.

 

[duplo]

Is there any reason not using IVS ?

 

[Perimeter]

Is there any reason not using IVS ?

Yes

 

[duplo]

What reason ? Having fun getting false triggers ?

 

[Perimeter]

Actually, since I set sensitivity to zero, I only get humans and cars. Which is what I want.

So basically, SMD works totally independent from the specific settings of motion detection - only requires motion detection to be turned on. SMD will also trigger motion detect when it sees human/car.

 

[bigredfish]

It applies to the entire scene though I believe…but good to know

 

[Perimeter]

It applies to the entire scene though I believe…but good to know

You can prevent SMD detects by using privacy masks. I don't, but it works.