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When alarm detected, record camera for x minutes

Posted: Wed Mar 19, 2008 11:36 pm
by Jason_Bassett
Hello

I have set my cameras to record only when motion detected.

One thing I notice (perhaps its just my settings though so please let me know if I can tweak them) is that when I view recorded events ZM generally records only part of it and I miss the final pieces where someone walks back into shot for example.

I think it would be useful to be able to have an option to "Record alarmed camera for XX minutes after alarm has ended." to ensure full capture of any events.

J

Posted: Wed Mar 19, 2008 11:59 pm
by coke
Mine feels kinda random. Like it'll tell me in the events list that it has .67 seconds, yet has 4000 frames. I'm not in a position to post logs/screen grabs until morning, but if anyone has a clue, I'll take it. :)

I certainly messed with my settings on the Buffer tab, to attempt to get my on-camera detection working sensibly, and after I gave up on that I tried ZoneMinder's own. Wouldn't be shocked if the problem was there.

ZM doesn't seem to detect much false motion in my setup, so I'd like to make it record 30 seconds or so after it stops detecting motion. I decided that after my axis's seemed flakey on when they would detect it, or at least when the TCP event would trigger something.

Also, when it does seem to be continually detecting motion, it would be nice if it split the events into chunks based on the specified event size.

Posted: Thu Mar 20, 2008 3:08 am
by cordel
Set the post alarm buffer for the number of frames for that duration:
@5fps capture rate
duration 30 seconds

5x30=150
post buffer = 150

http://www.zoneminder.com/wiki/index.ph ... uffers_Tab

Posted: Thu Mar 20, 2008 5:48 pm
by coke
Ok, I have them all set to 150 now, restarted ZM and wandered off for awhile. Here are the results, do they look weird?:

Code: Select all

Id 	   Name 	        Time 	        Secs 	Frames 	Score 	
54682 	Event-54682 	03/20 12:38:28 	0.84 	198/8 	6/7 	
54679 	Event-54679 	03/20 12:36:58 	0.78 	199/9 	5/6 	
54678 	Event-54678 	03/20 12:36:31 	0.90 	198/8 	6/8 	
54671 	Event-54671 	03/20 12:34:32 	0.80 	199/9 	6/7 	
54666 	Event-54666 	03/20 12:33:20 	2.37 	219/29 	5/6 	
54662 	Event-54662 	03/20 12:32:32 	1.58 	207/17 	6/9 	
54658 	Event-54658 	03/20 12:31:49 	12.80 	433/48 	5/6 	
54656 	Event-54656 	03/20 12:31:33 	5.58 	297/39 	5/7 	
54651 	Event-54651 	03/20 12:30:41 	1.23 	207/17 	5/6 	
54646 	Event-54646 	03/20 12:28:59 	1.39 	192/2 	5/5

Buffer settings:
Image Buffer Size (frames) 40
Warmup Frames 25
Pre Event Image Count 40
Post Event Image Count 150
Stream Replay Image Buffer 300
Alarm Frame Count 2

The camera claims 30FPS, it shows up as a variety of speeds in zoneminder.

Posted: Thu Mar 20, 2008 6:54 pm
by cordel
Okay but if you are recording at 30 fps then setting your post buffer to 150 is only going to give you ~five seconds.

150/30=5

Also the seconds column is the cumulative time of the alarmed frames I believe, not the entire event.

Posted: Thu Mar 20, 2008 7:32 pm
by jameswilson
Yes it is the alarm time not the total event duration.

Posted: Thu Mar 20, 2008 8:14 pm
by coke
Thanks. That makes much more sense.