Video
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12.7.4
VMD detection window
The VMD detection window shows up as a small picture within the larger picture. Depending on
the thresholds set, the motion detection bar on the right side of the picture shows up green or
red (see figures below), the latter indicating a VMD alarm will be generated. In the pictures, the
upper and lower thresholds are shown as two white markers. If the bar runs over the highest
marker, it will turn green again and there will be no alarm condition.
VMD detection windows, with mask applied to the left half of the window. The small white blocks
indicate grid elements where change occurred above the sensitivity level. The summed change is
reflected in the bars on the right, the green one (left) not reaching the lower threshold. The red one
(right picture) extending past it, since this threshold is set much lower.
12.7.5
VMD alarm
If movement is detected, a module alarm (VMD) will be generated and sent out over the network
using the (unsolicited) notification mechanism. Such alarms can be caught using appropriate
software.
12.7.6
Advanced
Video > VMD > Advanced > VMD
Item
Description
Frame rate divider
Range: [1...100]. Used to determine the number of frames used for VMD. Only 1
divided by this value frames are evaluated.
Delay
Range: [1...10] frames. The delay in frames between the currently processed
frame and the stored frame with which it is to be compared.
Event window size
Range: [1…32]. Number of frames evaluated at a time to determine if there is a
VMD alarm.
Event window low mark
Range: [0…31]. Thresholds determining if there is a VMD alarm.
Event window high mark
Feedback position
Enables you to position the detection window (not to be confused with an event
window).
