Difference between sensibility and threshold

Thank you very much !

Now I am searching a setting like “motion duration”. I tried “trigger duration” but it doesn’t do what I want. I would like to trigger a “motion event” only if the “event” is still in motion after X seconds since the first motion was detected. Is it possible ? Maybe this feature is not available yet I can’t find it.

Regards,

JB

The Trigger Duration sets how long time a video is recorded after a motion trigg. If you get a motion trigg during that time it will continue to record with another Trigger Duration time.

By using a Rule you can start an event at the same time as the motion trigger. But, in NCS there are not today support for a delayed start of a second event. However, with an external home security systems it would be possible. There are people here on the forum that sends data from NCS to their home security systems.

-Henrik

Hi,

I am just trying to get my settings all working well and this has been really helpful.

When working with the threshold value does this consider only the area that is selected for motion detection or does it consider the whole picture? Ie if I had only 10 percent of the picture enabled for motion detection would the threshold relate to a percentage of this 10 percent? (Not the whole capture image)

Cheers,

Hi!
Very interesting question! That is a programming issue and I do not know that. Your question is actually if the Detection Zone affects the Threshold value. I have to direct this question to our developer @Steve to answer.
-Henrik

It still considers the full picture because masking is only forcing and area to be black so that it’s not being detected. so it’s 10% of the full picture not 10% of the selected area.

Anyway the best is to display the gauge / meter while configuring to be able to compare what is reported compared to the target you have or to rely on blob detection which seems more much efficient.

On Threshold…

My views are broken into a grid of 16x24 which is 384 squares. Setting a threshold of 1 should exclude an object smaller than 3.8 squares. I don’t see that the threshold correlates to a percent of the view.

With a threshold set to 2 (should exclude an object smaller than 7 squares) - I am still recording on very small objects moving in the view. My cat will set off my basement camera to record every time. Or a rabbit (smaller than 1 square) still sets off another camera; same camera at nights will be activated by an insect which even up close is smaller than 1%.

Insects and tree shadows are the main issues I have at this time with false alarms.

Hi!
It’s about the number of pixels of the image sensor in the camera.
-henrik

Same here! Henrik’s explanation was great, but it just doesn’t seem to mesh well with the actual threshold settings in Netcam Studio. I have my threshold rather high to try to remove a bunch of my false readings, but still get recordings of insects and sun/cloud shadow changes on the ground that drive me crazy.

If only NCS could detect and differentiate between objects, people, etc. rather than just pure movement…

Hi Gunn!
I certainly agree that it is a drag. I have the same problems especially with shadows that are dancing on the walls. It would be very nice to have a software that could do what you propose. There are software’s or rather systems for that, but they comes with a completely different price tag. Have you tested using another Motion Algorithm.

Problems with insects are usually when the IR is on. To get away from that people usually set up a separate IR source away from the camera. Insects do like the IR since it is very bright for them and also generates heat.

Sorry, but it´s not that much more I can suggest than the above.
-Henrik

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I realized about a week ago that I could turn off the IR on the outside camera and get a much cleaner night time image with the ambient light. I turned up the brightness on the camera a bit to compensate too. I realized the IR was causing too much visual noise from insects, dust, and precipitation and false motion events. I hadn’t thought about using a separate IR light-- thanks for the idea! I also always wondered why the camera was an insect magnet-- I am constantly clearing off spiders, flies, etc. Thanks for the tip that insects are attracted to the IR-- it makes sense now!

Excellent and glad to help!
-Henrik

I too am struggling with insect false alarms. Also with alarms if there is a glitch in the image and all pixels shift, for example. What would be ideal for me is to require 1 to 2 seconds of motion to set alarm, and then save clip starting -5 seconds back from buffer. I would like to ignore drastic motion like entire image shifting by 1 pixel or a bug flying across image in less than a second. I think requiring 1 to 2 seconds of motion – the same motion target (so is that a blob?) would eliminate most of my false alarms.

Or some other method or reducing “noise” in the image in the form of bugs and camera glitches. Maybe cut everything moving beyond a certain velocity because nothing out many feet from the camera can move as fast as the bugs flying across the camera very close.

Some software I have tested has “ignore motion of less than XX milliseconds” setting. Is there something like this in NCS? Or another setting in other software that I have seen is minimum/maximum object size. Setting a max object size would remove camera pixel shifts (just noticed not all are glitches – some are vibrations from doors opening/closing).

What would be my best approach using settings available to me?

What will the setting “Threshold 0” do?

I noticed that setting it to 0 was “automatic” so I thought maybe some logic there would help but still lots of false alarms. Hundreds last night. Does it improve over time? Maybe it’ll be better tonight? Also not sure which method I should use for detection – seems like maybe “blob” (is this an object like person/animal/vehicle?) but the manual only says “The algorithm counts moving objects and highlights them with red rectangle.” I’m less interested in the count of moving objects… I need to identify a single object of interest that is moving.

I have had it set to background.

It is a little confusing as to why you can choose a display (algorithm?) different than the “motion algorithm” itself. I would think that the purpose of the display would be to help you understand what the “motion algorithm” is doing so shouldn’t it always be set to correspond?

CA_Tallguy, do you use a high or a low resolution camera? I found that going from a very cheap 640x480 to a good 1920x1080 reduced the sensitivity. I actually kind of have the opposite problem, motion is not picking up smaller things, like the neighbors cat pissing on my stairs… I guess that an object appears larger when it’s on a picture with less pixels.

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Usually, higher resolution cams cover a larger viewing angle which is the big effect.

What will the setting “Threshold 0” do?

What will the setting “Threshold 0” do? Distance and high resolution makes every moving objects a low pixel count object, so I guess I should use a low Threshold value, but what is the difference in “0” and “1”?

Hi Remi,
Sorry for late reply.
-Threshold=0 is an automatic calibration. The system checks the average noise level and set the level to 10% above that. If Threshold is set to 0 and there is no noise Threshold will be set to 1, but it is still in Automatic mode.
-Set Threshold manually to 1 is extremely low and the system will trigg for any group of pixels that is interpreted as moving. This can be noise or actually an object that moves.

What is best is always tricky and will depend on situation. If you know quite well what object you want to detect and about how much of the area it will cover then a manual set can be good to minimize false alarms. If it is difficult to say the automatic mode might be better.