User manual

DV-IP User Manual v1.01 Feb 28
th
2003
DV-IP User Manual
22
VMD
VMD, or Video Motion Detection, allows cameras to automatically detect changes in the scene
that they are monitoring, and perform a number of actions such as notify an operator, or
increase camera recording rates if required.
To establish the best settings for VMD, it is recommended that you undertake testing based
on different Pixel Count and Pixel Change settings. Too high a setting will miss activity,
and too low will cause false triggers. The Walk Test will help set the optimum levels by
providing a thumbnail image where triggers are seen on screen. VMD triggers can also be
seen on the Live View as boxes that appear when that particular area is triggered.
VMD Camera Enable - Activates VMD on a per camera basis.
VMD pulse extension - This extends the time in seconds that an alarm is valid for, before
another trigger event is activated. For example, if a door with a pulse extension of 10 is
opened triggering an alarm event, but closed immediately, the alarm event will still last 10
seconds – and thus the increased recording rate lasts for the full 10 seconds rather than
slowing again once the door is closed. If the alarm is opened twice within the pulse extension
period, this will only count as one alarm, rather than 2.
VMD Pre-Alarm (Image protection) - The minimum protection period before the VMD
trigger.
VMD Alarm Duration - The duration of a VMD alarm – i.e. the length of time for which a
VMD alarm is ‘in Alarm’ and thus performs ‘in Alarm’ action e.g. increases record rate.
VMD Protect Period - The time period the images will be protected from being overwritten.
Create Database Entry - Records an event in the database using the VMD zone number.