|
All fire safety professionals
constantly seek the benefits of early warning of
potential fires. In the perfect world they imagine being
able to place hundreds of smoke detectors millimetres
above and around the items or areas at risk. This would
certainly enable a fast response to a potential fire,
saving valuable time even in voluminous areas or where a
high airflow may be present. But of course such a dream
is not possible from a practical or financial point of
view - OR IS IT?
Top of Page
CCTV Smoke
Detection is based on sophisticated
computer analysis of the video image seen by the CCTV
camera (sensor). Using advanced image-processing
technology and extensive detection algorithms (and known
false alarm phenomena); the VSD can automatically
identify the distinct characteristics of smoke patterns.
The fire detection industry has an abundance of known
smoke signatures and all of these are built into the
system to give an accurate decision on whether smoke is
present. The VSD is so accurate in its analysis that it
can even differentiate between steam and smoke.
The CCTV Smoke
Detection system uses standard CCTV
equipment linked to a self contained processing system
which is capable of recognising small amounts of smoke
within the video image and alerting the system operator
both at the processor and by a variety of remote
outputs.
The CCTV Smoke
Detection system employs highly
complex algorithms to process video information from up
to eight cameras simultaneously. Under normal conditions
with all eight cameras connected the system achieves a
5Hz-frame rate for each channel.
The video hardware is designed to
allow simultaneous real time digitising of all eight
images, which means that the system does not multiplex
images and, therefore, no information is lost or
delayed. All alarm condition images are logged, time &
date stamped, and stored within the system’s memory.
The CCTV Smoke
Detection system detects smoke
rapidly by looking for small areas of change within the
image at the digitisation stage and only passing these
pixel changes to the main processor for further
filtering.
The video information is passed
through a series of filters, which seek particular
characteristics that can be associated with smoke
behaviour. Further analysis is then carried out on the
relationships between the filtered characteristics to
determine whether all the conditions have been met for
the system to confidently predict the presence of smoke.
The system installer has the
ability to vary the amount of smoke signal, and the
length of time that the smoke exists before an alarm
condition is raised to cater for situations where there
may be background smoke present. The installer may also
divide the video image into zones and programme the
system to alarm only if smoke is present in two or more
zones.
Top of Page
The CCTV Smoke
Detection system comprises of a
high-grade industrial computer, mouse, keyboard and VGA
monitor. Proprietary high performance video grabbers are
housed within the computer. The VGA monitor will display
the digitised video image from any one of the four
cameras in detection mode, all control and set-up
graphics, zonal layout information, pre-alarm and full
alarm information, zone and camera identification in
alarm.
The FireVu system can be
connected to the loop-through outputs on your DS2 DVR to
maximise your investment in your camera hardware, as the
cameras can provide surveillance and fire detection
functions simultaneously.
|