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Alarms: Work with some, not all cameras

Posted: Tue Jul 05, 2016 1:22 pm
by melloa

I'm testing the configuration below, running on a dedicated server:

ZM system info:
You are running the most recent version of ZoneMinder, v1.29.0.
Operating system CentOS Linux 7.2.1511
Kernel and CPU Linux 3.10.0-327.18.2.el7.x86_64 on x86_64
Processor information Intel(R) Core(TM) i3-4160 CPU @ 3.60GHz, 4 cores
CPU usage 9% user, 1% kernel, 0% IO, 90% idle
Real memory 3.07 GB used, 15.46 GB total

Cameras info:
2 x d-link DCS-5009L Firmware Version 1.07.05 (2015-11-18) - Indoor

HTTP/24 bit colour/640x480; host path: /video.cgi

3 x sercomm OC432 F/W version: V1.0.01R08 - Outdoor

HTTP/24 bit colour/640x480/mjpeg; host path: img/video.mjpeg

1 x foscam FI8919W Firmware Version - Outdoor (linked to one of the sercomm)


The issue I'm having is that with the two cameras (d-link - indoor) i have no problem setting up zones and alarms work fine with default settings.

The outdoor cameras are not alarming 99% of the time.

My researches took me to lots of information on ... or_Dummies and, but even following the recommendations I've found I still can't make those cameras to alarm.

Basically I'm monitoring three troubled areas:

- Driveway with two zones to ensure best coverage and exclude the road to avoid alarms from passing cars; best-high sensitivity pre-set.
- Front porch with three zones monitoring a windows, the walkway, and the front door; same setting as above.
- Back porch with two areas monitoring the stairs and the floor area; same setting as above. This camera is linked to the foscam for a broader view recording.

I've also have used the configurations from Zoning system for Dummies (above link) and played with the setting trying to make it work to no avail.

Any ideas how can I troubleshoot the configurations to fix the motion detection will be appreciated.

Re: Alarms: Work with some, not all cameras

Posted: Tue Jul 05, 2016 3:10 pm
by knight-of-ni
Yes, the default settings will never work outdoors 99% of the time. Every camera view is different and there simply is no setting one can program ahead of time which will work in most/all cases. You have to tune the cameras yourself. You've taken the first step and read the documentation. Many don't. The number of settings to tweak is a double edged sword. For those that understand them, it makes ZoneMinder very powerful. However, all the settings are rather difficult to understand for beginners.

I've lost track of how many times I've given the following answer to this repeated question, so you'll have to use the search tool to find instances where I have given more details.

The short answer to motion detection is to set your motion detection settings to be extremely sensitive, then work your way towards being less sensitive once you identify the false alarms. It doesn't work the other way around. I typically set the units to pixels, rather than percent. Pixels are much more precise for outdoor views.

With the sensitivity turned up, you need to go look at the motion statistics for each event to learn how many pixels "moved" during the event. This will give you an idea of what values to put into the motion detection settings.

Re: Alarms: Work with some, not all cameras

Posted: Tue Jul 05, 2016 3:24 pm
by melloa

I'll research more, now filtering by your name. And sorry if I've asked questions already answered on this forum, but so far I've not found anything that could guide me through the tweak process.

Will continue trying.

Thanks again!

Re: Alarms: Work with some, not all cameras

Posted: Tue Jul 05, 2016 9:04 pm
by melloa
Here's some thoughts:

Disclaimer first - Nothing against the author of the article or knnniggett. Just trying to make sense of things and learn.

From: Understanding ZoneMinder's Zoning system for Dummies

Which detection type should I use?
I personally feel to detect "humans", blob is the best. As I described above, it combines Alarm + Filtered + ensures that the pixel differences are contiguous and then does an algorithmic analysis to see if it forms 'blobs'
Pixels or percents?
What makes more sense to you? "Raise an alarm if 178pixels are changed" or "Raise an alarm if more than 20% of my zone has changed?". To me, the latter makes much more sense. So I've always used percents

From those statements I've started trying to fine tune my cameras, but as stated on my 1st post wasn't successful.

When posting here and getting a reply from knnniggett, I looked at his posts regarding zones and found:

Based on the requirements you have stated, I would start with the following settings:
Define a zone that covers the area of interest (or move the camera closer)
Units: Pixels
Alarm Check Method: AlarmedPixels
Min/Max Pixel Threshold: Leave at default for now
Min/max Alarmed Area: Start decreasing this number

So it might be my misunderstanding of this software, but I'd assume both are right as x pixel in y area would translate to z% of the same y area, but decided to go with pixels as had tried % before.

After reducing the min pixels to about 1% I started getting alarms on my cameras, so one step forward on my configuration.

So, for future references of new users like me (the ones that actually read the forums and research) are the rules of thumbs?

- Define your zone;
- Select Default configuration;
- Change unit to pixel;
- Change alarm to AlarmedPixels;
- Play with the min alarmed area (in my case default was 2% and I got alarms with 1% of the total area).

Again, not saying % is wrong as per article, just stating that above worked better in my case for outdoor cameras monitoring my driveway. Indoor worked out-of-the-box, no changes needed, so camera by camera/indoor/outdoor changes everything.

Re: Alarms: Work with some, not all cameras

Posted: Tue Jul 05, 2016 9:32 pm
by knight-of-ni
I agree with you, and I always recommend using pixels, rather than percentage, because it is more precise... and it always works. Not everyone agrees, which is probably why you read something different.

Using percent is easier and it scales with your view if it ever changes, but it doesn't work in every case. Sometimes you need sensitivity that is not a whole percentage point, especially when you have a large view. Using Pixels gets you much finer control, but you've got to pay attention to the statistics that zoneminder generates for each event and then use that to fine tune your settings. A high megapixel camera with the right field of view might take a large truck to trigger 1% of pixels of be counted as "motion". In that case, you'd have no choice but to switch to pixels if you want to detect mere humans.

Alarmed pixels work for general motion detection where the objects of interest are reasonably big within the field of view and there are no other objects moving in the field of view (e.g. trees, clouds, etc). However, you are left wondering exactly what, within the field of field, zoneminder thought was moving.

Blob detection outlines the motion in red, which is why it is so handy when you are tweaking your motion settings.

So it sounds like you made progress, but it does not sound like you've looked at the statistics generated at the event. Try opening a recorded event and click on the frames column. Click around and you can open up each frame, with the motion outlined in red. You can also get ZoneMinder to tell you exactly how many pixels were triggered ....which is exactly what you need to fine tune your settings.

Don't get too carried away though trying to make them too precise... the settings change with your environment (e.g. when it gets dark, cloudy day, etc)

Re: Alarms: Work with some, not all cameras

Posted: Tue Jul 05, 2016 9:52 pm
by melloa
Thanks knnniggett. I'll wait for night to check how the setting will react with motion light, etc. I did found the frames and saw the alarms, so could compare what was been considered to trigger the alarms.