What does anti dither do?

Have some questions or having issues with your IP Camera(s), Post them here for the mods and other users to assist you with.
User avatar
longedge
Site Admin
Posts: 584
Joined: Fri Mar 31, 2017 9:34 am

What does anti dither do?

Post by longedge »

I'm not clear on what "anti dither" does. Does it stop further events triggering for the set time?

I would like to extend recording for an extra 20 seconds after the last movement is detected. Is it this setting I should be looking at? Does it control whether a new event is triggered during the event which is being recorded?
My AMCREST Cameras:-
2 x IP3M-941B firmware V2.620.00AC00.3.R, Build Date: 2019-12-18
1 x IP2M-841B firmware V2.420.AC00.18.R, Build Date: 2019-08-03
locolbd
Posts: 9
Joined: Wed Jun 21, 2017 10:06 pm

Re: What does anti dither do?

Post by locolbd »

Anti-dither is the amount of delay that will occur before the DVR starts recording, it can also be thought of as the amount of time something in the image has to be there to trigger the DVR to record. Masking is blocking of certain sections in the image to turn off the motion detection of that part of the image
How to Prevent False Alarms with Your Security Camera System
https://www.securitycameraking.com/.../ ... ra-system/
User avatar
longedge
Site Admin
Posts: 584
Joined: Fri Mar 31, 2017 9:34 am

Re: What does anti dither do?

Post by longedge »

I only record to onboard SD card but I imagine the same holds true.

What I'm looking to do is to keep recordings going a bit longer because they stop while the person triggering the event is still in the picture (but leaving).
My AMCREST Cameras:-
2 x IP3M-941B firmware V2.620.00AC00.3.R, Build Date: 2019-12-18
1 x IP2M-841B firmware V2.420.AC00.18.R, Build Date: 2019-08-03
Mildew
Posts: 47
Joined: Tue May 31, 2016 8:03 am

Re: What does anti dither do?

Post by Mildew »

No, that's not the correct for Amcrest cameras. The Anti-dither is the amount of time the camera stays triggered. For example, if the anti-dither is set for 30 seconds, the camera will record for 30 seconds.
User avatar
longedge
Site Admin
Posts: 584
Joined: Fri Mar 31, 2017 9:34 am

Re: What does anti dither do?

Post by longedge »

That makes sense, and during that time I take it that it does not further respond to activity?
My AMCREST Cameras:-
2 x IP3M-941B firmware V2.620.00AC00.3.R, Build Date: 2019-12-18
1 x IP2M-841B firmware V2.420.AC00.18.R, Build Date: 2019-08-03
Mildew
Posts: 47
Joined: Tue May 31, 2016 8:03 am

Re: What does anti dither do?

Post by Mildew »

I believe that's correct.
chadbaldwin
Posts: 14
Joined: Wed Apr 06, 2016 9:28 am

Re: What does anti dither do?

Post by chadbaldwin »

Okay, now I'm confused...

So I set these settings:
Anti-Dither: 0 seconds
Record Delay: 10 seconds
Pre-event Record: 5 seconds

I turned on a light via Wifi (so that there is nothing else moving in the room), this triggered motion. The video file created was 17 seconds long...I suppose that makes sense...
5 second pre-record
2 seconds for the the camera to adjust to the light change.
10 second delay
= 17 second video

Then I upped my Anti-Dither to 30 seconds keeping everything else the same, and did the same test. The new video was 46 seconds long...
5 second pre-record
30 Second Anti-Dither period
10 second delay
= 45 second video (the extra second can probably be ignored)

Then, keeping the settings the same, I turned the lights on again...triggering motion...then 13 seconds later (I tried for 10 but the smartphone app has a delay) I turned them off again, triggering motion again. This time the video was 61 seconds long...this is where I am confused...If the point of Anti-Dither is to ignore motion during those 30 seconds, then shouldn't my 3rd test produce the same length video as the second test? Since my second motion event was within 13 seconds of the first motion event, then it should have been ignored, right?
Mildew
Posts: 47
Joined: Tue May 31, 2016 8:03 am

Re: What does anti dither do?

Post by Mildew »

I believe that if motion is detected again during the delay time (not the anti-dither time), then that's a new trigger and everything starts over (beginning with the anti-dither time).
lemmy999
Posts: 16
Joined: Sat May 14, 2016 12:38 pm

Re: What does anti dither do?

Post by lemmy999 »

Mildew wrote:I believe that if motion is detected again during the delay time (not the anti-dither time), then that's a new trigger and everything starts over (beginning with the anti-dither time).

But if you look at his description, his second event was 13 seconds after the first event. So that was well within the 30 second anti-dither time. It was not during the delay time. So that should not have been a new trigger and everything shouldn't have started all over. But it seems that is what happened.
benlagraine
Posts: 1
Joined: Tue May 28, 2019 4:00 pm

Re: What does anti dither do?

Post by benlagraine »

The anti-dither is the period in which the DVR (or camera) does not capture any movement. After this time period ends, then, this feature would inform the video recorder to begin recording the footage.

A grizzly bear suddenly walks in your backyard as seen through the PTZ camera. Before this movement of the animal is captured by the DVR, 10 seconds have to end first.

After that delay time that you set, then, the actions of the grizzly bear, such as scavenging in your trash bin, would be recorded in the DVR.

Apparently, the concept of anti-dither is about the amount of time an object has to be in front of the camera in order to trigger the DVR to capture the footage.

Setting the anti-dither time to zero would result in zero delays. The DVR would record any movement that is immediately seen through the security camera.

As the anti-dither time pertains to the amount of delay that will take place prior to the DVR begins its recording function, within one anti-dither time frame is classified as a new event.
Post Reply