Tripwires --- ugh, I need help!

JesseSR

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I really need some help here. Trying to setup alerts in my Dahua camera and NVR so that a particular camera (it looks out towards the beginning of my driveway) catches "vehicles" coming UP the driveway into the property.... BUT I do not want vehicles to trigger when they are leaving the property! IVS Intrusion won't work for this because it needs DIRECTION. For reference, this a picture of the camera view, and the black arrow shows the direction UP the driveway towards the property/building.

1629839945499.png



This next picture shows the 3 different places we've TRIED drawing a single directional A->B tripwire at (to be clear, testing using a single IVS rule with 1 tripwire, NOT three IVS rules each with 1 tripwire), regardless of which of the 3 places we've drawn them, the success rate is ONLY about 50% of detection a Vehicle coming up the driveway, which is completely unacceptable and worthless to me.
1629840349022.png



Next, I learned about drawing zig-zags (from users on this forum, I was excited to try this!). So I drew a single IVS A->B tripwire rule like this, which gives the vehicle -many- more chances to "trip" the tripwire on the way UP the driveway.
1629840460248.png



The problem is... SIGH Even though the tripwire is directional A->B , half of the lines in the zig zag are directioned UP the driveway, and half of the lines in the zig zag are directioned DOWN the driveway (every other lines switches direction), which means... using the zig-zags alerts me whether vehicles are coming UP or going DOWN the driveway.

In other words, using zig zags , effectively creates this directional flow as far as the tripwires:
1629841313309.png


I cannot have the alerts triggering when someone is leaving the property and going down the driveway. I was told these Dahua cameras are 98% effective at this stuff, but in reality it's like 50-75% at BEST. I need this for security reasons. Pleading here with anyone that can offer help or a way to make the zig zag method work when a vehicle is only going in ONE direction (UP the driveway).

I'm at my wits end here. I spend $16k on a camera system (we have many more cameras) that Dahua claims is 98% effective but right now, it seems like the detection is junk and better off being thrown in the garbage. Willing to PAY for a solution, and for help here, that solves the problem and is 98%+ consistent.


(yes I'm aware we need to draw the lines for a 3-d view, and we are doing that)
(yes, I've thought about having 4-5 individual IVS rules on the camera, each of them being a separation A->B tripwire, but then I might get 2, 3, 4, or 5 alerts for a single vehicle coming up, which seems ridiculous too.)

PLEASE HELP. ??
Really struggling with this...

J
 

wittaj

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Your approach to this with several individual trip wires is correct and I employ that same method on two of my cameras with great success (see below). ZigZag is problematic for the reasons you stated for what you are trying to accomplish.

Which camera model is this (need to know if it is AI capable or doing it through min object sizes) and if it is an AI camera, did you do the global config/setup to calibrate the field of view?

The image looks a little blurry and that may contribute to the problem? Is this happening day and night or only night?

Post a screenshot showing the full IVS rule page showing min. object size, etc.

Are you running auto/default settings - this results in motion blur ghost instead of a human or vehicle at night and can cause the motion detection to miss. It needs to be able so see contrast to make out the shapes.

Once you dial it in to your field of view, and do the global config to calibrate the camera, then you will start to see results.

I have got IVS to work in a blizzard utilizing the same idea of yours of only needing triggers in one direction:

1629844258896.png

and this crazy shot where I will preface this with this camera is dialed in to this location for when the flood lights come on, so that is why the picture is so dark. One of the big issues people do not account for is what happens when a floodlight comes in - if the camera is on auto/default settings, the image will look ok when the floodlights are off, but then the camera gets temporarily blinded when the floodlights turn on or the image is too bright and it misses IVS motion. So the best option is to dial it in for when the floodlight is on knowing that they will kick on and you will get a great capture once they do. I have several IVS tripwires to only trip in one direction as this is being used as a spotter camera to turn my PTZ.


1629844270120.png


It comes down to configuring your camera and dialing it in to your field of view and using a test subject to walk around while you are adjusting with the IVS rules on during live view to see when and why it is triggering.

Auto/default settings are usually going to be problematic. Auto shutter at night was probably a motion blur ghost and didn't look like a human.

And some field of views will be problematic as well. YMMV.

In my opinion, shutter and gain are the two most important and then base the others off of it. Shutter is more important than FPS. It is the shutter speed that prevents motion blur, not FPS. 15 FPS is more than enough for surveillance cameras as we are not producing Hollywood movies.

Many people do not realize there is manual shutter that lets you adjust shutter and gain and a shutter priority that only lets you adjust shutter speed but not gain. The higher the gain, the bigger the noise and see-through ghosting start to appear because the noise is amplified. Most people select shutter priority and run a faster shutter than they should because it is likely being done at 100 gain, so it is actually defeating their purpose of a faster shutter.

Go into shutter settings and change to manual shutter and start with custom shutter as ms and change to 0-8.3ms and gain 0-50 (night) and 0-30 (day)for starters. Auto could have a shutter speed of 100ms or more with a gain at 100 and shutter priority could result in gain up at 100 which will contribute to significant ghosting and that blinding white you will get from the infrared.

Now what you will notice immediately at night is that your image gets A LOT darker. That faster the shutter, the more light that is needed. But it is a balance. The nice bright night image results in Casper during motion LOL. What do we want, a nice static image or a clean image when there is motion introduced to the scene?

So if it is too dark, then start adding ms to the time. Go to 10ms, 12ms, etc. until you find what you feel is acceptable as an image. Then have someone walk around and see if you can get a clean shot. Try not to go above 16.67ms (but certainly not above 30ms) as that tends to be the point where blur starts to occur. Conversely, if it is still bright, then drop down in time to get a faster shutter.

You can also adjust brightness and contrast to improve the image.

You can also add some gain to brighten the image - but the higher the gain, the more ghosting you get. Some cameras can go to 70 or so before it is an issue and some can't go over 50.

But adjusting those two settings will have the biggest impact. The next one is noise reduction. Want to keep that as low as possible. Depending on the amount of light you have, you might be able to get down to 40 or so at night (again camera dependent) and 20-30 during the day, but take it as low as you can before it gets too noisy. Again this one is a balance as well. Too smooth and no noise can result in soft images and contribute to blur.

Do not use backlight features until you have exhausted every other parameter setting. And if you do have to use backlight, take it down as low as possible.

If you decide to throw them in the trash, I will send you my address and you can mail them to my trashcan, um I mean mailbox :p
 
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sebastiantombs

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Another thing to do, just as good practices for setting up a camera, is to look at the tabs in the IVS section, got to "global setup" and calibrate the camera. That will take three sticks, 1 meter long, space out in the field of view you're interested in and allow the camera to have some size "comprehension".
 
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JesseSR

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@wittaj ---- Thanks for the detailed message. Quick question for you (I'm sure I will have MORE) if you don't mind.. regarding your set with having the the 3 INDIVIDUAL IVS tripwires on the same camera (so 3 rules, instead of just 1) --- do you get 3 alerts or just 1? I wanted to do the zig-zag because I really don't want multiple alerts for a single vehicle coming up the driveway, that would suck. Were you able to configure your 3 individual IVS tripwires and still just get a single alert?

(currently, we have the iVS tripwire on the driveway camera set (theoretically I mean, as the success rate is currently 50-70% at best) so when a vehcile crosses the tripwire in the driveway, an alert is then triggered and then activates a relay in the DVR, which is then hooked up to an RTI system, which then audibly announces that a "vehicle is approaching" through the speakers in the building -- unfortunately, the success rate is really low right now, so it's basically worthless.

One other quick question, if the driveway camera is only 5.5' high, is that going to be a problem? Must IVS detection videos I see, show the camera like 20' up in the air looking more down... I didn't know if that matters much or not, especally when the vehicles are coming towards the camera?


@wittaj @sebastiantombs We will look at doing the Global Config as well. Would you recommend the global config for ALL of our cameras (we have 8 and some are more consistent than others for all the iVS detections).

Thanks for the FAST responses. We will review your recommendations as well and report back.
 

JesseSR

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I should also mention, right now we're just focused on DAYTIME with the cameras. I'd like to try and get that dialed in first I guess and then focus on the NIGHTTIME.. The driveway cameras (we have two) have (2) cameras in them, one regular one, and one Thermal camera. So, 2 units, but basically 4 cameras. I'm not sure the model #'s off hand, but I will try to find that out for you since you asked.

Also, the cameras DO have min/max object sizes too. They're higher end cameras from Dahua, not cheap ones.
 

sebastiantombs

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Just as a good practice it is a good idea to calibrate for IVS. Anecdotally, some people have excellent results with IVS and some don't. I can't say why the big disparities from installation to installation, but would guess it's related to lack of calibration and fine tuning of the image. Some people also put tripwires or intrusion boxes right against the edges of the view frame which doesn't let the camera "see" something cross a line or enter/exit and intrusion box.
 

wittaj

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I only get one alert unless someone stops in between the IVS lines and stands there long enough for the alert time to end and it restarts. Otherwise, just a person or car going by normal, just one alert.

Max/min object sizes have nothing to do with higher end or lower end Dahua cams as all Dahua has that. Which camera model are these? If they have AI that you select human and/or car, then you start with minimum object size as zero. You only put in a min object size if the camera has AI as an effort to eliminate false triggers. So if the cameras have the human and vehicle check boxes, make min object size zero and watch the accuracy improve... Mine are all at 0,0.

Your height and angle seem to be ok. As I mentioned, it is usually a result of poor setup due to not doing the global config calibration and running on default settings.
 

JesseSR

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Sorry for spamming my own thread, heh. Regarding the models of the cameras themselves, this is the invoice I received for the system
1629850833941.png

The yellow highlighted cameras are the (2) driveway cameras. 8mm, Thermal, and they are the "Eye" variety. I'm having trouble finding a "eye" version with 8mm, and thermal on Dahua's wiki or website though. I'm going to have to look a bit deeper. The (2) driveway cameras were $839 each and I would guess not marked up very much (my resellers seems fair on pricing).
 

JesseSR

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Just as a good practice it is a good idea to calibrate for IVS. Anecdotally, some people have excellent results with IVS and some don't. I can't say why the big disparities from installation to installation, but would guess it's related to lack of calibration and fine tuning of the image. Some people also put tripwires or intrusion boxes right against the edges of the view frame which doesn't let the camera "see" something cross a line or enter/exit and intrusion box.
Yea, we learned that you can't really do tripwires or intrusion boxes right along the edges of the viewframe, so we've stayed away from doing that. We will look into doing the Global Calibration as that hasn't been done yet.... hopefully Thursday.
 

wittaj

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OK that camera has AI in it, so make sure you do the global config and change min object size to 0,0.

Are you having it trigger based on image or thermal identification?

And if you decide they are trash and throw them away, I will take that trash LOL
 

JesseSR

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I only get one alert unless someone stops in between the IVS lines and stands there long enough for the alert time to end and it restarts. Otherwise, just a person or car going by normal, just one alert.

Max/min object sizes have nothing to do with higher end or lower end Dahua cams as all Dahua has that. Which camera model are these? If they have AI that you select human and/or car, then you start with minimum object size as zero. You only put in a min object size if the camera has AI as an effort to eliminate false triggers. So if the cameras have the human and vehicle check boxes, make min object size zero and watch the accuracy improve... Mine are all at 0,0.

Your height and angle seem to be ok. As I mentioned, it is usually a result of poor setup due to not doing the global config calibration and running on default settings.
This is good to know that you only get 1 single alert even with multiple IVS tripwires. Maybe I can try setting up 5 separate A->B tripwires on the camera then, so long as it's just one single alert. Where do you set that alert time value before it restarts? What setting is that?

The cameras do have separate IVS AI boxes for Human and Vehicles. We use 1 driveway camera specifically for Human detection, and 1 driveway camera specifically for Vehicle detection right now. We did this so that we can have different alert/relay/alarm notifications sent out depending on if a Human or Vehicle are coming up the driveway.

We've had to use some of the min/max settings so far, because if we don't the Human or Vehicle IVS will pick up small animals like foxes or skunks. So I don't think the min object size is 0 anymore.? I think Dahua tech support asked us to increase it from 0 to prevent the false positives. Does that sound correct?
 

JesseSR

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Your height and angle seem to be ok. As I mentioned, it is usually a result of poor setup due to not doing the global config calibration and running on default settings.
One more thing to mention about that comment. It's hard to gauge in the picture I posted but, the driveway has a pretty decent slope to it. From the beginning of the driveway to where the camera is (I'd guess around 100' in length, there is an elevation change of about 25-30' or so. So it's a big uphill/downhill climb). So the vehicles are literally going up/down the driveway as they approach or leave. Maybe calibration would help with that too.
 

JesseSR

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Are you having it trigger based on image or thermal identification?
Hmm, I guess I'm not sure what you mean by that. Each physical driveway camera (one for detecting Humans, one for detecting Vehicles) has (2) cameras inside of it, a regular one and a thermal one. As far as I know, the cameras are triggering based on images, I don't know how to check if they're triggered based on thermal? (Sorry, this stuff is really new for me.. my installer could better anwer this but I won't see him until Thursday).
 

wittaj

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Ok, so yes, if you were getting false triggers due to small animals, then yes you would set a min object size. However, if they didn't do the calibration, that could cause it, so I would have them do that and reset them to 0,0 and see if that takes care of it.

There is a slight chance that the field of view is so straight on that the AI isn't capturing a vehicle. A lot of times they are more side shots of the vehicle. None of my cameras have that type of straight on shot to test or confirm for you, but I would think it should work based on what I see.

You set the "break time" for the alert within whatever program you are using to store and send the alerts. Since you have an installer, I am assuming it is an NVR.

I am not familiar with this exact model, but usually the thermal cams allow you to set up the trigger based on the thermal image "footprint" to further reduce the false alarms, so it should see the heat signature differences between the surroundings and a vehicle or human and trigger. @bp2008 has some experience with thermal cameras and can probably offer my advice.
 

JesseSR

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You set the "break time" for the alert within whatever program you are using to store and send the alerts. Since you have an installer, I am assuming it is an NVR.
Just wanting to clarify... I'm hoping that, if I setup 4 or 5 individual A->B tripwires for IVS, that I will only get a single Push notification in the DMSS app on my Android phone, instead of getting 4 or 5 push notifications for that 1 single vehicle. (We can easily set the RTI system to not re-send alerts for 15 seconds or so... that's pretty easy) Is it possible to not get 4 or 5 individual Push notifications to my phone when a single car goes up the driveway if I use 4 or 5 separate trip wires? Thanks for that clarification!
 

wittaj

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Yes that would be correct, at least in my experience. But I am sure someone somewhere has it set up differently and they do get multiple alerts, but you should be able to take care of it in settings.
 

Mike A.

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I only get one per "event" with multiple tripwires and an intrusion box that covers the same area. All get tripped generally when someone comes in my driveway and/or up my walk. But I'm using BI and its app, not DMSS. Still, the trigger for the alert is coming from the camera and BI is just passing along in this case.
 

JesseSR

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I only get one per event with multiple tripwires and an intrusion box that covers the same area. But I'm using BI and its app, not DMSS. Still, the trigger for the alert is coming from the camera and BI is just passing along in this case.
I thought DMSS was the app used for viewing your Dahua cameras and getting Push notifications on my Android phone? Not even sure what BI is (don't want to hijack my own thread here, heh). I'm glad to learn though it's possible to have multiple IVS tripwires on a single camera and not necessarily generate multiple alerts/alarms/push notifications for each one , in the case of a vehicle coming up the driveway. Will put this on my to-do list for Thursday.
 

Mike A.

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BI = Blue Iris. A popular VMS. Sorry, discussed a lot here and we get used to using the shorthand.

I don't have any experience using DMSS on Android. I would ~think~ that it would work in the same way since it's just reacting to the trigger as passed to it by the cam but I don't know that for a fact. But then there's also the NVR involved and I don't know how that's set up and how it interacts with the cam for events.
 
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