Manual

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Firmware User’s Manual V7.00.44
61
Trigger threshold
Look at the moving object entering the area of motion detection: although moving quite slowly, it
caused motion activity – several pixel regions reported a motion that was faster than allowed
“speed limit” of sensitivity (70).
A 10% trigger threshold means, 10% of this motion detection area were filled with moving pixels
at that moment. By visual observation you can also see that the object standing inside the motion
detection region indeed covers about 10% of its size.
What if the object is really small but moves rather fast (gets triggered by the current sensitivity
level)? For example, we want to detect people but not the cat walking in the room. Although both
people and cat may move with the speed that will trigger motion, they have different size of
triggered pixels. For example, a human passing by the motion detection region will trigger 25% of
pixels in that region while the cat would trigger only 2%. Since we want to have a real alarm in
case of human or vehicle passing by while ignoring birds, cats, butterflies, mice, etc, we need a
filter that can define how many percent of triggered pixels will be considered as a real alarm. This
parameter is called trigger threshold. The default value of trigger threshold is 10%. It means,
only the objects that are bigger than 10% of the motion detection region size and move faster
than allowed by sensitivity level (70) will produce actual alarm.
How to choose the most optimal trigger threshold level? The rule of thumb, keep the trigger
threshold as small as possible while not causing false alarms by the moving objects that
are not humans or vehicles.
You can have different sensitivity level and trigger threshold level for each motion detection
region.
In order to understand all of the above even better, please refer to the table below containing four
possible combinations of settings using sensitivity level and trigger threshold percentage.