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it is possible to prevent generating a false alarm, e.g. by a bird
flying across the surveillance area. Select the desired value by
moving the slider to the desired position with the mouse key held
down.
Object min size [n*] blocks:
the number of sensor cells, which a moving object must cover in
order to generate an alarm, can be specified. In this way it is
possible to prevent too small objects from producing an alarm. For
this, the minimum recommended value is 2 (2 × 2 sensor fields).
Select the desired value by moving the slider to the desired
position with the mouse key held down.
Alarm indicator:
to prevent false alarms, a motion signal can be matched to a given
alarm threshold. In this way, for example, it is possible to filter out
effects caused by the background noise generated in the camera
itself. The blue line indicates the alarm threshold. Any value greater
than this will produce an alarm signal. The components of the
motion signal generating the alarm are indicated in red. The alarm
threshold can be varied to suit individual requirements.
Take note of the amplitude of the movement signal displayed in the
window over a long period and at all light levels likely to be
encountered in practice. Move the mouse pointer onto the blue line.
Holding the left mouse button pressed, move the blue line to the
required position.
Motion tracking:
for certain applications, it can make sense to generate an alarm
only if movement takes place in a particular direction. You can
activate the motion detection and select the direction of movement
required to generate an alarm. Select here the option
On
, in order
to activate the motion tracking feature of the video sensor.
Tracker:
in the
Tracker
field you see an arrow, which indicates the current
motion in the video image. By means of check boxes in the four
corners, the desired direction can be activated. If, for example, all
movements to the “left” and “upwards” are to activate an alarm,
then mark the top left corner. If all movement to the “left” is to
activate the alarm, then check the left upper and the lower left
corners. Note the movements indicated by the arrow in the video
image over a long period and at all light levels likely to be
encountered in practice. Click the check box in order to activate the
corresponding directional component.
