I've been using ZoneMinder for quite a number of years, mainly for monitoring remote locations, and it's been working great -- thanks everyone for the nice work!
Recently I wanted to start using its motion detection capabilities too, and unfortunately I've hit a problem that I can't seem to resolve.
In a nutshell, it all works perfectly until there is the first real motion event, but after that ZM considers absolutely every frame as an alarm frame; basically the event never ends and fills-up the whole storage space with gigabytes over gigabytes of data, which then becomes impossible to process into one file and has to be deleted.
The settings seem to be fine, because the actual recording doesn't start when there is no movement, and I can see frames coming in and being ignored. As soon as there is enough change to warrant an "alarm frame", the whole thing starts rolling. It looks like the system never "resets" the comparison frame and it keeps comparing to that first alarm frame, even when the object is long gone.
For example, if I put my hand in front of the camera, the event starts and records; then when I remove the hand, the recording continues indefinitely, even if the image is now static; looking at the Timeline it seems as if an increasing amount of alarm pixels happen as time progresses, while in reality all images look the same. If I manually stop the even and start the process again, everything is quiet until I move something in front of the camera, then the whole thing repeats.
At first I tried this with the default settings, and I thought I had mis-configured something. Then I started playing with various options, but nothing changed no matter what I selected:
- Different presets (Fast/Best, Low/High sensitivity)
- Buffers -- the default:
Image Buffer Size (frames) 40
Warmup Frames 25
Pre Event Image Count 10
Post Event Image Count 10
Stream Replay Image Buffer 1000
Alarm Frame Count 1
- There is only one zone configured which covers the whole image area
- Monitor set to "Modect", logs mainly green
- ZM package from repositories: zoneminder-1.25.0-4
- Hardware: Dual-Core i5-3210M CPU @ 2.50GHz w/SSD storage
- Camera: Logitech OrbitAF PTZ over USB
- Resolution: 800x600
- Various devices on various OSs, all using Firefox 22.0 as the browser.