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Setting Threshold Values
For each included box, you must set two threshold values—sensitivity and size.
Table 1-4
Threshold Settings Fields
Field
Description
sensitivity
Specifies how much a pixel value must change to be considered
significant. Sensitivity values range between 0 and 255. Auto
(default setting) should be sufficient for most applications.
Auto is high enough to filter out most noise and slight lighting
changes, and low enough to detect most motion. If this does not
give appropriate detection for your application, select a lower
value to increase sensitivity to pixel value changes, or a higher
value to decrease it.
Note
Setting sensitivity to 255 triggers only with a change
between absolute black and absolute white. Sensitivity
values under 10 often trigger from imager noise even when
no motion is visible to the eye.
size
Specifies how many pixels in a box must change (by the
sensitivity) so that enough change has occurred to trigger motion
detection. Size is given as a percentage of the number of pixels in
a box so it has values between 0 and 100.