Fine Tune Zone
Posted: Mon Nov 27, 2006 1:58 pm
I have zone stats on, but I just wonder "how" to fine tune my zones. I could use "trial and error", but since my zones are very sensative I have at least 200 events to help me work out the right settings.
I can see that a zone might be defined thus:
And that the stats for an alarmed frame might show this:
mysql> use zm;
mysql> select * from Stats;
So surely I should be able to identify:
Which areas on the image are causing the most false alarms
The correct threshold (assuming I know which are falsies and which are true events)
But only if I knew how to link the stats to the Zone definition... is this in a FAQ somewhere that I haven't found yet?
I can see that a zone might be defined thus:
Alarm Check Method [Blobs]
Min/Max Pixel Threshold (0-255) [20] [ ]
Filter Width/Height (pixels) [3] [3]
Min/Max Alarmed Area [8] [ ]
Min/Max Filtered Area [6] [ ] Min/Max Blob Area [5] [ ]
Min/Max Blobs [1] [ ]
And that the stats for an alarmed frame might show this:
I can drag out each alarm frame statistic by typing:Zone [Zone1]
Pixel Diff [26]
Alarm Px [5954 (34%)]
Filter Px [4906 (28%)]
Blob Px [4858 (27%)]
Blobs [1]
Blob Sizes [3797 (21%)]
Alarm Limits [178,141-319,186 ]
Score [28]
mysql> use zm;
mysql> select * from Stats;
So surely I should be able to identify:
Which areas on the image are causing the most false alarms
The correct threshold (assuming I know which are falsies and which are true events)
But only if I knew how to link the stats to the Zone definition... is this in a FAQ somewhere that I haven't found yet?