JVC VN-C3U NETWORK CAMERA
Computers continue to play an increasingly important role in
video surveillance, though to date it has been mostly confined to control, support
and peripheral applications. JVC’s ‘V.Networks’ technology moves the PC much
closer to the action and provides us with an intriguing foretaste of things to
We’ve been looking at the VN-C3U network camera and its
associated control software, which turns any reasonably up to date
network-capable Windows PC (95/98/NT etc.) into a powerful surveillance tool in
its own right. The VN-C3U is one of a number of recently introduced ‘network’
cameras from JVC, this the most sophisticated model with the camera mounted on
a remotely controllable pan/tilt mechanism. The camera also has a remote zoom
function, position memory, two alarm inputs and the control software has still
capture and recording facilities. However, before we get too involved with the nuts
and bolts, a few words on what it does and how it all works.
The concept is simple enough, just plug a VN-C3U camera into
a suitable LAN hub, dial-up router or directly into a network-equipped PC and
you can remotely monitor the camera location from the PC desktop. Depending on
the size and structure of the network the camera and control/monitor PC could
be in the same office or building, or separated by hundreds or thousands of
miles. The LAN ‘environment’ used by the VN-3CU is the 10Base-T fast Ethernet
standard, which benefits from being very widely used, flexible and robust. It
uses relatively simple cabling and configuration can be quite simple. As an
added bonus Ethernet adaptors are now fitted to a growing number of PC
motherboards as standard.
A network camera and control system has a number of
advantages over a conventional analogue CCTV set-up. The most obvious one is
remote or distant operation, without the need for any additional cabling. This
also makes it very flexible, cameras can be easily added and removed from the
system, and being PC based there’s no need for any additional hardware. The
downside, at this very early stage of the game, is image quality and bandwidth.
Network technologies – such as Ethernet – and digital video processing systems
simply cannot match the performance of coaxial cable and analogue video. The
bottom line is that images are not as detailed or fluid but in many
applications the compromises are perfectly acceptable and more than compensated
for by the system’s flexibility.
It’s time for a closer look at the hardware. The business
end of the VN-3CU is a colour camera based around a 1/3-inch CCD with a 300k
pixel array. It has a F1.8 lens with a 10x optical zoom (5.8 to 58mm focal
range). The system has provision for three preset resolution setting (160 x
120, 320 x 240 and 640 x 480 pixels). Picture data is processed using JPEG
compression and display rates are variable at between 5 and 30 frames per
second. The camera is mounted on a compact pan/tilt platform giving 320-degree
pan and 90-degrees tilt ranges, both at up to 100 degrees per second. The unit
is designed to be ceiling mounted though there’s an image inversion facility,
which allows for alternative mounting arrangements. Connections to the outside
world couldn’t be simpler, it requires a 12 volt DC power supply, via a set of
screw terminals, two-way data goes via a standard 10Base-T port (RJ45
connectors) patch lead to a network hub, or direct to a PC using a ‘crossed’
cable. Alarm inputs and output are carried on a set of spring contacts.
The camera unit weighs in at just 730g and is mostly
constructed from high-impact ABS plastic. It looks and feels reasonably robust
though in the absence of a protective housing it needs to be mounted well out
Software installation is reasonably straightforward; for the
record the minimum PC specification calls for a 133MHz Pentium/Pentium class PC
(preferably faster) with at least 32Mb RAM (64Mb recommended), 20Mb hard disc
space and 10Base-T LAN capability. It’s designed to run under Windows 95, 98 or
NT. Out tests were conducted using a 500MHz Athlon PC and Windows ME, using a
direct connection to the camera via a cross-wired cable.
Prior to installing the software the PC’s network connection
has to be configured with an IP (Internet Protocol) address; this procedure is
clearly explained in the generally easy to follow instruction manual. The
software is loaded from a CD-ROM and on our test rig it look less than a minute
to install, after that it’s necessary to run a second configuration utility
from the CD-ROM, enter the IP address, identify the camera and carry out
preliminary adjustments, such as setting the image view (normal or upside
down), set flicker frequency (50 or 60Hz) and set up a password, if required.
The initial setup also covers the basic alarm functions and actions
(send/receive over network, go to preset position, relay etc).
When that’s done the ‘Controller’ software can be run and
the connection with the camera established, if all’s well this only takes a few
seconds. The Controller opens with two windows: the main control panel and the
display screen, the size of the latter depends on the resolution; the midway
320 x 240 setting is usually the best compromise for screen area and visibility.
In addition to showing the camera image the display window can also be used to
control pan and tilt, by clicking the mouse pointer into the sides or corners
of the picture.
The control window is divided into three main areas. On the
right is the camera ID/selector drop-down menu and a row of ten preset position
buttons. To the right of that are the PTZ and zoom controls, and at the bottom
of the window are the video recording and still/snapshot keys. Other functions
are accessed from a set of drop down menus.
The Setting menu is the most important and this contains
sub-menus for adjusting picture quality and compression rate (high, medium or
low), saturation and colour balance and manual/auto gain, contrast and
brightness. The frame rate sub-menu also has a direct bearing on image quality
though in practice it is largely determined by the capabilities of the network
and the PC. Position memory is used to store camera position and zoom settings.
The Lens menu covers auto/manual iris, auto/manual focus and zoom position.
Alarm settings control alarm responses on the PC (pop-up message, recording
start, play wav (sound) file or execute a program file), and the Time Stamp
option superimposes time and date information on the image (7 display styles are
The recording function can be enabled at any time, clicking
on the Record button automatically opens a new file, identified by time and
date. Still or snapshot recording allows up to 16 images to be captured at a
time, after which they have to be named and saved, otherwise the ‘Snapshot’
button is greyed out. Video playback is easy with speed and direction control
available using a standard Windows-type progress bar. Video recording – even
relatively low resolution material such as this -- uses up vast amounts of disc
space, between 6 and 10Mb per minute, though much depends on the quality
settings, resolution and frame rate. Long term or continuous recording is only
an option on PCs fitted with very large hard disc drives.
Pan/tilt action under preset control is smooth and fast,
manual control, using the direction buttons on the screen, or by clicking into
the display window, is disappointingly jerky. Each mouse click moves the PT
mount in preset increments and this has an impact on the image, which judders
in sympathy when the camera moves, making it difficult to follow a moving
subject or object. Ironically zoom action is continuous and much easier to
In comparison with a typical analogue video system picture
quality is very average. There’s a reduction in the amount of fine detail,
colours are coarse and the picture can be quite noisy. Nevertheless, in good
light it is capable of producing useable images and the camera’s exposure and
white balance systems cope reasonably well with changing lighting levels. The
auto focus lens is also quite fast and responsive and only needs manual
intervention in low light situations.
Network camera technology is improving all the time and
clearly has a bright future, particularly with the growth in fast broadband
systems. However, current network systems impose significant limitations on
picture quality but against that must be weighed the simplicity and flexibility
of installation, and valuable features, like ease of use and still and video
recording. We suspect there are plenty of situations, retail premises and
offices for example, with existing PC networks, where a trade off of image
quality against convenience is acceptable.
Power supply 12 VDC
Weight 730 g
Dimensions 122 x 82 x 97mm
Product design 8
Build quality 8
General functions 8
CCTV functions 7
Ease of use 7
Manuf. support ?
Video quality 7
R. Maybury 2000 0611