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Quick Test for Remote Video
Calibrating Tamper Detection for Cameras
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Scheduling
The video archive can be spot-checked for recorded video when cameras are
scheduled to record it. Refer to Scheduling in the
Recorder System Administrator
Vandalism
Tampering with cameras, the DVR or other hardware. This can be done by
damaging hardware directly or indirectly interfering (by spraying paint, fog or moving
objects in the way), or even through reconfiguration, using View software. Allow for access
to the DVR, if maintenance is required, yet prevent easy criminal tampering with the system.
Dew, frost or kitchen grease
the subject for transparency and cleanliness.
Darkness
Without lighting or infrared cameras, indoor rooms and nighttime can make
cameras ineffective.
Cameras at an outside window
the window can hamper or block visibility outside.
Opaque objects
Even small objects can obstruct a camera when near, hampering an
operator's view of a site. Large mobile objects, such as a truck also can be used to
compromise video of an event. Work around camera blind spots due to architecture, mobile
equipment, vehicle docking, construction and so on.
Power outage
Even when plugged into a UPS, a prolonged power outage compromises
the recording of video.
Calibration of tamper detection requires that a System Administrator has set up tamper
detection on a camera to trigger an alarm or to be logged, and that an operator use
LocalView or a remote operator use View.
Blind
A camera can be blinded by too much light or too little. To calibrate, cover the
camera with an opaque cloth or box, or prop a strong light in front of the camera for more
than 48 seconds. Less time than this does not trigger an alarm or log entry. This amount of
time is designed to reduce the number of false positives. Check with the operator if an alarm
or log entry has occurred. Remove the opaque cloth. Turning the lights off at the scene can
also trigger tamper detection, as can panning a PTZ camera from a light colored scene to
a darker scene (or the opposite). Lowering the threshold can compensate. Blinding a
camera also triggers the Blur-type and Scene Change-type of tamper detection.
Blur
It is not recommended to alter a camera's focus, once set. To simulate sabotage of
focus, use a lens-like sheet of glass or plastic, or a transparent container of water, and prop
it in front of the camera during calibration.
Scene Change
After a System Administrator has rearmed an alarm produced by the
Scene Change-type of tamper detection, move the camera back to the scene that the
organization needs to monitor.
The Blind type of tamper detection can be used for fixed and for PTZ cameras.
Blur and Scene Change tamper detection are designed for fixed cameras only, not for
PTZ use. Using pan, tilt or zoom functions will trigger Blur and Scene Change.
Rapid Eye™ Multi-Media Digital Video
Guide.
Check camera lenses, or windows between the camera and
In a room that remains lit during evenings, reflection from
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