SURVEILLANCE VIDEO
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Introduction
SURVEILLANCE VIDEO
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Cash Registers
For this situation,
install high-resolution,
varifocal cameras.
Varifocal cameras
have adjustable lenses
that allow you to get
exactly the picture you
want—zoom in to get
a tight image with lots
of detail, or zoom out
for a wide overview.
Illuminate the area
well, but never point
a camera directly at a
light source.
Entrance
If your storefront is made
of glass, the lighting will
change over the course of
the day. Most cameras will
show you a completely
washed-out picture. If this
happens to you, you need
a Wide Dynamic Range
(WDR) camera, which lets
you view the very dark and
very bright parts of the
picture simultaneously.
Diagram courtesy of Swann
Typical Retail Setup
Selecting the best components is the hardest part of
setting up a surveillance system. Not every camera
will work for every application. At B&H, we can
help you nd the right cameras for your speci c
needs, without breaking the bank. Here, we’ll look
at a common purpose for surveillance equipment:
minding the shop when you can’t be around.
SURVEILLANCE
VIDEO AT A GLANCE
GETTING STARTED A CCTV (Closed Circuit Television) system consists
of a camera and monitor. Choose your wire (see the “UTP or Coax” box,
opposite) and connect these components. Plug the camera into a power
supply. Congratulations! You’ve just built a CCTV system.
WHAT IF YOU CAN’T ALWAYS WATCH THE CAMERAS? You’ll need to
record the video stream from the cameras. In the past, special VCR’s with
time-lapse capability were popular. You’d program them to record so many
pictures (or frames) per minute; a lower frame rate allowed more video to t
onto a single VHS tape. Otherwise, recording to VHS tape could get expen-
sive quickly. e trade-o was that more compressed video rendered fewer
details, because only a few pictures per minute were recorded. VCR’s only
recorded one channel of video, too. For multiple cameras, you’d have to con-
nect the VCR to a “mux,” or multiplexer, splitting the screen into 4, 9, or 16
segments, one for each camera. Picture detail was almost imperceptible.
ENTER DVRS Digital Video Recorders (DVRs) were a huge step forward.
ese are essentially computers that record video to hard drives. Hard
drives cost much less than their equivalent in VHS tape, and DVRs can also
record multiple cameras. Video storage used to be measured in hours; it’s
now measured in days, weeks—even months. DVRs use video data proces-
sors to compress the video, cramming more video into the same amount of
space, storing higher and higher frame rates (FPS or frames per second). 24
FPS is reckoned as “real time.” Even 12 FPS seems close to real time. Many
security pros use 7.5 FPS as the standard recording rate. Many DVR’s have IP
connections as well, allowing Internet connectivity via a PC and a router. As
of this writing, Mac-compatible DVR’s are rare.
THE CAMERAS Choose the right camera. Will it always be dark? Will you
need a camera to enhance available light? Outdoor cameras should have
infrared illuminators to allow night vision. Will part of the picture be very
brightly lit and partly dark? A camera with Wide Dynamic Range (WDR) and
dual shutter speeds will take each zone of the picture and expose it properly,
allowing you to see a complete image of bright and dark areas.
FIXED VS. PTZ PTZ (Pan Tilt Zoom) cameras allow you to move the camera
remotely until it’s oriented correctly, and to zoom precisely. ese individual
cameras are expensive—the price of four or ve xed cameras, typically—so
only install a PTZ to cover large, open areas such as parking lots or lobbies.
LONG-TERM ARCHIVING Backing up your data is always a safe bet. Hav-
ing a great deal of hard-drive space installed on the DVR is a good idea,
because you can search for video from the DVR control program. On the
other hand, this can become expensive. Another option: back up video to
an external hard drive. You will not be able to search using the DVR’s search
lters, but the data will be protected in case anything destroys the DVR,
such as theft, ood, re, or electrical surges.
A WORD ABOUT PRIVACY Before installing CCTV, check the local laws
regarding privacy and recording. Never install video or audio surveillance
anywhere there is a reasonable expectation of privacy, such as in bath-
rooms, locker rooms, changing rooms, medical examination rooms, etc.
Never record another person’s private property without permission.
Security is a huge concern for today’s
home and small business owner. With such
a bewildering number of system options
available, B&H can help you fi nd the perfect
solution to fi t your needs and budget.
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