CYCLOPS MULTI-IMAGE FIELD STORE
WHAT OUR EXPERTS SAY...
There’s a widely held belief within the
electronics industry that magnetic tape’s days are numbered, as the primary
recording medium for video and audio information. In the short term -- possibly
within the next ten years -- digital magnetic and optical disc systems will
almost certainly replace tape in many applications -- including, we suspect
video surveillance -- though the
ultimate goal is a completely solid-state recording system, with nothing to
Microchips instead of video cassettes are
still some way off, though maybe not as far as some people imagine. In fact
they’re already with us in a limited form; several companies have developed
solid-state digital cameras, that can record both still and moving images,
though the cost and capacity of the current generation of memory chips remains
prohibitive. Nevertheless, microchip memory prices continue to fall, driven on
by the PC industry and this has clearly been a key factor in the development of
the Cylops multi-image field store, from The Vision Research Company.
Cyclops is a digital solid-state video storage
device with a capacity of 64 frames, divided between 8 switched and alarmed camera
inputs. Each camera input channel has its own independent storage facility,
that can hold 8 frames of colour video information. Image resolution is 512 x
256 roughly equivalent to the quality of a standard VHS recording. The digital
picture information is compressed into a 12 megabyte RAM memory, this can be expanded
to 24 megabytes -- doubling recording capacity to 16 frames per channel --
using an extra three standard 4 megabyte PC memory boards or SIMMs (serial
in-line memory modules).
It’s housed inside a 19-inch 2U steel rack
housing, with the main on/off switch and a set or simple push-button controls
on the front. The eight camera inputs and monitor output (all composite video)
use BNC sockets. Alarm inputs, external keyboard and the communications port use a set of 9 and 15 pin D-Sub plugs
and sockets. A standard IEC socket is used for the mains supply.
The controls are arranged in four groups. The
first group (from left to right) is: memory clear and record; next come the four
replay buttons (play, multi-display, forward and reverse frame stepper). Close
to the centre of the panel are the 8 camera input selectors and sequence enable
button. On the far right, is the ‘config’ button, which calls up the
configuration menu, a power-on indicator and the main power switch.
When the Cyclops is active, images processed
by each camera channel are stored and refreshed sequentially. Vision Research
aptly compare this recording technique to a slowly spinning wheel, with 8
segments or memory slots. Images on each wheel or ‘loop’ are automatically updated
or overwritten once every revolution. If an alarm event occurs, then a preset
number of images preceding the activation are frozen, along with those that
follow. Once full the store will not be updated, thus preserving both pre and
post-alarm information. The refresh rate or ‘snatch’ time can be varied from
0.5 seconds to 4 seconds per frame. The number of frames captured before and after
the event can be altered. Recordings can be downloaded onto tape, (good to see
it still has some uses), for archiving or analysis, and to clear the unit’s
memory. We understand that the latest version of Cyclops have new software,
with a provision for automatic VCR recording of alarm events; this has to be
done manually on our review sample.
Recorded frames can be played back in
sequence and stepped forwards or backwards, they’re displayed along with time, date
and camera information. A multi-frame display option shows all of the images
stored in the loop in 3 x 3 format, in the case of an 8-image sequence, or 4 x
4, for machines set up to capture 16-image loops.
Cyclops is controlled by a password
protected-configuration system, based around a menu-driven on-screen display.
All important parameters can be altered, including a 32-character ident for
each camera input, the sequence dwell time for the display, alarm
configuration, printer set-up (for
producing hard-copy printouts of alarm activity), and the communications port,
for interfacing external devices.
Operation is reasonably simple, though it
helps to have the instruction manual to hand as some control operations are not
particularly intuitive, moreover it’s relatively easy to loose or overrite data.
It’s also worth pointing out that video information is stored on a volatile memory,
and everything -- apart from the alarm log, which covers the previous 50 events,
and configuration settings -- is lost if the power is switched off, or interrupted.
As the video information is stored digitally on
microchips, access time is almost instantaneous, there’s no picture noise, and
no degradation due to tape wear or noise.
Resolution at just under 240 lines comparable
with standard VHS, though colour definition is quite coarse and it has a rather
narrow grey scale. Of course much will depend on the camera input, and care
taken during the initial set-up, but by the time loop recordings are downloaded
onto VHS, images can begin to look a little whiskery.
Cyclops is a clear illustration of what digital
recording technology can do now, and provides a taste of what is to come, but
it poses one important question: does it do anything more, or work any better
than an existing technologies? The simple answer has to be no, though having
the functions of a switcher and recording device in one box is very convenient and
it may well be that Cyclops will turn out to be inherently more reliable than
tape as there’s nothing to wear out, and it doesn’t require regular servicing.
The bottom line is, Cyclops uses a lot of expensive and complicated technology
to capture a small handful of still video images, with the same kind of picture
quality as several hundred hours worth of material recorded on a relatively
inexpensive VHS time-lapse VCR, with a switcher or multiplexer, that together
cost around half as much.
Design and design features ****
Circuitry and components ****
Ease of installation and wiring ****
Range and variety of functions ***
Accompanying instructions ***
Technical advice and backup ****
Value for money **
Ó R.Maybury 1996 3010