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TECHNICAL TIPS

Ask The Expert about... 235

“Video Motion Detection” or
“Instant Detective”
What’s the difference?

VYigdoeuet orseectoMitrdouetpdiohfnoopoitDnaggeetyeouctwioilnl You can set up most DVRs to “activate” recording when the DVR senses
movement in a particular area, this is called “Video Motion Detection” or
6WSterChiCtgoyaug:nnpecrlielntutocysoroierorucenocdr:todlywintmay not VMD for short. This is obviously quite a useful feature. For example, using
& the thief VMD you could set up a DVR to record only when there is movement in
a car park thereby only recording video footage that may be useful if an
10off !! event occurs in that car park.
However there is a big problem with VMD! What happens if the DVR
Vs doesn’t trigger to record as the DVR doesn’t detect the movement? If
this happens you have zero footage recorded! This can and will happen
Instant Detective will as VMD is triggered by what it thinks is movement in video by changes
in the light levels. Because of the “tolerances” used to trigger VMD
You set it up knowing you recording sometimes it will miss events. Conversely, sometimes it will
get recorded footage record “non-events” due to changes in light levels on bright sunny days
with intermittent cloud cover as the DVR thinks the changes in light as
Why: everything to analyse clouds move over the sun is movement in the picture.
So although VMD has uses, it also has flaws which is why many
Records companies insist on 24/7 continuous recording. This means each
10 10laCtFeoTornohlceplruossoifmo&nat:irmte camera’s footage is recorded all day everyday regardless of if there is
saving. movement in the picture or not.
So if you are recording continuously wouldn’t it be great if you could
option! then “analyse” a particular area, doorway, shelf and see what movement
occurred within that area in the already recorded footage? Well you can
with Instant Detective!
Instant Detective searches through OLD video recordings stored on
the DVR for movement in a particular area so you can find out what
happened in seconds without trawling through hours of footage. (Unlike
VMD you know the incident will be there with Instant Detective as you
record everything all the time)

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