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Using the internal web pages
Global
threshold
low/high
These settings relate to the summed amount of change within fully or
partly unmasked portion(s) of the screen; a value between the two
thresholds gives rise to a corresponding VMD alarm. The level of this
alarm can be set (A-N) using separate Optelecom-NKF software.
VMD response
Fast
or
Filtered
. Filtering is used to suppress a single peak as false
triggering.
7.7.5.3 VMD Configuration 2: Setting the mask
To set a mask
1.
Under the preview, click
Edit mask
A grid is put over the image.
2.
To edit the mask, click on the grid
One or more mask elements at, and possibly around, that position, are produced.
3.
Hold the standard mouse button and drag, to ‘brush’ (i.e. mask) larger areas, with a
‘normal’ brush (coarse) or a ‘small’ one.
4.
To clear mask elements, set transparency to 100% before clicking on the grid.
Brush
-
Normal
Allows grid elements to be accessed in 5-elements groups
(crosses).
-
Small
Allows grid elements to be accessed one at a time.
Transparency
Values between 0 and 100% allow to the application to take contributions
from motion in not fully transparent areas into account, adding these
diminished contributions to the amount of motion (change) in fully
non-masked areas (figures 7.42a, b).
Undo
Undoes the previous operation, if the mask was not saved first.
Clear
Clears the mask.
Save mask
Makes the current mask effective and stores it for later use.
Figure 7.41 Masking grid
