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[awitty]

Hi

Does anyone know how to prevent shadows and changes of light from triggering a motion detection event ?

On sunny days and high winds i get loads of false positives due to the shadow cast by tree branches moving.

I could exclude the entire area but this defeats the purpose of having the thing in the first place.

Thanks

[JavaLawyer]

Log into the DCS-2332L web UI and navigate to SETUP > Event Setup > TRIGGER and select Passive Infrared Sensor rather than "Video Motion Detection". This will force the camera to only use PIR to detect motion. Using this approach the DCS-2332L detects heat differential rather than "motion detection" which calculates pixel differences between adjacent video capture frames, which is why shadows are perceived as motion.

The one caveat is that PIR only works up to a distance of 5 meters.

[awitty]

Log into the DCS-2332L web UI and navigate to SETUP > Event Setup > TRIGGER and select Passive Infrared Sensor rather than "Video Motion Detection". This will force the camera to only use PIR to detect motion. Using this approach the DCS-2332L detects heat differential rather than "motion detection" which calculates pixel differences between adjacent video capture frames, which is why shadows are perceived as motion.

The one caveat is that PIR only works up to a distance of 5 meters.

Thanks JavaLawyer.  I'll give that a go.   

[JavaLawyer]

Great! Please post back after you've had a chance to test. 

[awitty]

Great! Please post back after you've had a chance to test. 

Do you know the motion detection settings  (such as sensitivity and capture area) still apply when you set the camera it PIR mode ?

[awitty]

Great! Please post back after you've had a chance to test. 

PIR is even worse.   Hundreds of false positives :-(

[JavaLawyer]

The only other suggestion I have to offer is switching back to motion detection and reducing the sensitivity. Please keep in mind that motion detection is based on an algorithm that detects pixel differences between successive video frames. Any change from one frame to the next (depending on the sensitivity) is interpreted as movement and will cause an event to trigger.

The camera can't discern what is causing the motion (e.g. shadow, person, clouds, etc.) as that would require an artificial intelligence layer on top of the motion detection algorithm to make those determinations.

[walkjp1]

On this camera it has two different settings that can help you with motion detection.  Sensitivity and Percentage.  Can someone explain better to me what the PERCENTAGE function does and how best to use it?

[JavaLawyer]

On this camera it has two different settings that can help you with motion detection.  Sensitivity and Percentage.  Can someone explain better to me what the PERCENTAGE function does and how best to use it?

The Sensitivity setting determines how overt the motion must be to trigger an event (i.e. subtle vs. drastic). The Percentage setting determines what percentage of the camera field of view must have motion activity to trigger an event. These two settings work in tandem to determine whether an event is triggered.

Examples.

• If the Sensitivity = 80% and Percentage = 1%, then a very subtle motion occurring in a 1% or greater area of the field of view will trigger an event
  
• If the Sensitivity = 80% and Percentage = 90%, then a very subtle motion occurring that takes up 90% or greater of the camera field of view will trigger an event.
  
  

Using these two scenarios, an oscillating fan on the far side of the room would trigger an event under scenario #1, but would not trigger an event under scenario #2, b/c the fan only takes up a tiny portion of the frame (e.g. 5%).

A person walking across the camera frame would trigger an event under both scenarios because the motion is occurring over close to 100% of the camera frame.

[JavaLawyer]

Adding to my last post, lets assume you only select 10 grid boxes in the frame for motion detection.

If the Percentage is set to 10%, then the motion only needs to occur in 1 grid box to trigger an event.
If the Percentage is set to 50%, then the motion must occur in at least 5 grid boxes to trigger an event.

[walkjp1]

Thank you JavaLawyer.  I`m having a lot of problems getting this camera to function correctly. Sometimes, I get images where I cannot see any movement. Sometimes one person walking in front of camera will send images. But sometimes 2 people in front of camera will not.