A prime example of the Internet Protocol 'revolution'
Much has been written about network video and the likely impact it will have on the surveillance industry, and a growing number of systems are now being installed. But only within the past 18 months has this revolutionary technology really started to take off, and its full significance is only just starting to be realised.
This upsurge of interest is largely due to a new generation of stand-alone network cameras or 'netcams' and video servers (the latter designed to work with existing analogue cameras). These make the installation of network surveillance systems as straightforward as – and potentially a great deal simpler than – conventional CCTV.
But why all the fuss when the end result is the same as any other CCTV setup, namely a live video image displayed on monitor at a remote location? Because network cameras are important for two reasons.
Firstly, sending video images over a computer network does away with the need for separate cabling and a centralised monitoring and recor-ding facility. Computer networks are commonplace in commercial premises and offices nowadays. The rapid growth in small local area networks (LANs) and home networking is getting a lot of people in the industry very excited.
Secondly, network cameras are microcomputer-based devices; they are effectively web servers with their own unique IP (Internet Protocol) address. In crude terms a netcam can be regarded as a self-contained website and images from the camera can be viewed on any PC connected to the network, in most cases using standard Internet browser software such as Internet Explorer and Netscape.
More importantly, if the network is connected to the Internet, images can be sent by email or accessed on any Internet-enabled device, from pocket PCs and mobile phones to laptops, theoretically from anywhere in the world.
The Axis 2130R – the subject of this Bench Test – is a prime example of the new wave of compact and affordably priced netcams now becoming available in the UK. Axis Communications has played a major role in the development of network video and remains the market leader in the face of rapidly growing competition from better-known brands within the surveillance industry.
The camera module is mounted on a motorised pan/tilt platform which, along with the camera's 16x optical zoom, manual/auto focus and exposure settings, can be remotely controlled from a browser window on a networked PC.
The basic camera specifications compare favourably with many general-purpose analogue colour video cameras and the 1/4-inch Sony ExView HAD CCD with its 768 x 494 pixel sensor array has a low light sensitivity of around 6 lux.
On table or ceiling
The camera is available in 'table top' or ceiling mounted versions (though why the image simply cannot be inverted in the control/admin software is a mystery). It can pan through 340 degrees and the tilt angle is 100 degrees.
Up to 40 positions plus 'Home' can be programmed and it is powered by an external mains adaptor. Images can be time and date stamped and there is a simple titling/ident facility. A set of input/output connections can be used for an external alarm sensor or to use the camera to control other external devices.
Thus far, apart from the eye-catching design, there is little to distinguish it from an analogue PTZ camera setup but this is where the two techno-logies diverge and you need to start thinking digital. Instead of a standard 625-line/50Hz PAL video signal the 2130R has a choice of image resolutions with either 176 x 112 or 352 x 240 pixels at frame rate of 30 frames/sec, or 704 x 480 at 10 fps.
The 2130R uses industry-standard JPEG still and motion-JPEG video file compression. Five levels are available which determine both the quality and the size of the image data files, which vary in size from 0.3 to 150kb per image. The camera is designed to work under a wide range of commonly-used networking protocols, including the industry standard 10/100 BaseT Ethernet plus TCP/IP, HTTP, FTP, SMTP, NTP, ARP, DHCP and BOOTP.
System requirements are minimal and it will work happily with all current PCs and operating systems, including all flavours of Windows, MAC OS and Linux.
A 4Mb flash memory is used to store pre/post alarm images and it has an upload application utility that can automatically send images to a website or to a nominated email address at specified intervals, or when the alarm input is triggered.
Physically the camera is remarkably compact. It may be difficult to tell from the photographs but the base/mounting module is a little thicker and around two-thirds the length of a VHS cassette.
The pan and tilt motors use a combination belt and worm drive gearboxes, the tilt motor is housed in one of the support arms while the pan motor is on a sub chassis inside the base module. The only external connections are on the rear of the base unit and comprise a standard power connector for the 13v DC supply, an RJ45 socket for the Ethernet connection and a four-way socket for the alarm/control input and output.
Inside the base module are two sub-assemblies. The lower one houses all of the networking electronics. This is based on Axis' own proprietary 'Thin Server Technology' consisting of a central processing unit or CPU, flash memory and DRAM memory modules. As a matter of interest the CPU, which is basically a stripped-down PC, uses a version of the Linux operating system that has a proven track record for robustness and reliability.
A second PCB, mounted on a metal chassis in the upper half of the base module, handles camera and functions and provides a firm base for the pan motor, gear-train and main bearing for the camera assembly. Inside the camera head is another densely-populated PCB and the main lens barrel with its tiny zoom motor and iris actuator. The camera head is housed inside a fairly thin plastic shell, while the base unit case is formed from a lightweight alloy.
No attempt has been made to weatherproof the camera or base unit so it is only suitable for indoor use. Moreover it doesn't look especially robust and needs to be mounted well out of harm's way.
With only two connections to worry about (power and Ethernet) installation should be relatively straightforward. However, in order to get the camera to communicate with a network it has first to be assigned an IP address. To do that it is necessary to open a DOS window on a PC connected to the network and enter a set of commands, the camera's new IP address, its assigned 12-digit Ethernet address (derived from its serial number) and the IP address of the PC or terminal being used.
The camera then has to be powered up and 'pinged' to make sure it is responding. None of this will be too much of a problem for anyone who has set up or had experience with network configuration but it may prove daunting to installers accustomed to conventional analogue camera systems. But even those with a good working knowledge of computers and networks are likely to be dismayed by the single sheet of setup instructions that accompanies the camera, which goes into no detail whatsoever, let alone any troubleshooting advice.
Setup & operation
In theory once the camera has been successfully assigned an IP address it can be accessed from an Internet browser simply by typing its address into the URL line. In practice we found this to be a somewhat hit-and-miss affair and we found that sometimes, after the power had been removed, we had to run through the setup several times before the camera could be accessed.
Once it is up and running it is very easy to use. The opening web 'page' shows a live view from the camera with what appear to be 'sliders' for controlling pan, tilt and zoom plus auto/manual focus and iris. There is also a button for 'Home' and a drop-down menu for programmed positions. This method of operation takes a little getting used to. To begin with the PTZ functions are quite coarse and there's a noticeable delay.
Even on a small network this can be in the order of half a second before the camera responds. On an Internet connection this could increase significantly. The PTZ controls are not very intuitive like a joystick or a normal Windows type 'slider' control, instead you have a choice: click the arrows at the end of the slider, to step the camera or lens by a small increment, or click into the slider to move the camera (or lens) to a position.
Since there is no visual feedback on the control bar it is quite difficult at first and that, coupled with the delay and the slow frame rate on the largest resolution setting, means it is quite hard to follow a moving subject.
Access to the camera's other functions is via the Admin button. This brings up a menu page with options for General Settings, Network Settings, Video Setting, Live View and two 'Wizards' for installation and Applications, the latter covering automatic scheduling, alarm settings and emailing or uploading images. The General menu covers time/date setting, security and passwords and customising the design of the pages with the user's choice of background colours and images.
Network Settings are concerned with the finer points of IP addresses and protocols and is best left to network administrators if the default settings prove troublesome. The Video Settings menu deals with time/date stand and camera ident, the image size, resolution and data compression level and setting the preset positions for the PTZ.
Because the image is digitally processed there is almost no degradation, whether the camera is connected to a local network, or viewed remotely via the Internet. Image quality is very good indeed and the 704 x 480/10 fps and default compression settings provide plenty of fine detail and good strong natural colours.
The camera's fully automatic white balance system adapts quickly to changing lighting conditions and although low light sensitivity is nothing special, it is still able to produce a useable image in relatively poor conditions. The iris and focus are reasonably fast but there is always the option for manual control.
The PTZ mount works well but it lacks some of the refinements we have come to expect from similar systems, in particular the linkage between zoom setting and pan/tilt motion, so that it is difficult so make fine position adjustments at higher zoom levels.
There is no 'auto flip' either, which comes in useful when a subject passes beneath the camera. The 340 degrees of rotation also means there is a blind spot behind the camera.
What the manufacturer says ...
Axis Communications has established itself as the market leader in the video server and network camera markets. The JPEG image format commonly used by Axis is now generally recognised as the de facto standard within the industry – largely because it delivers excellent quality for each image frame within a video sequence. The 2130 PTZ network camera is an all-in-one integrated device that fulfils the need for automatic and remote interactive control of the camera's positional orientation and zoom level. A single 2130 enables monitoring of large areas and locations that would otherwise require multiple fixed cameras for similar viewing coverage. The 2130 has a tremendous potential to reduce the total system cost and greatly simplify installations in a wide variety of applications. The 2130 is a pan/tilt/zoom video solution for monitoring large areas over standard networks. Including Auto Focus for rapid focus and quick access to quality images of surveillance objects, it is easy to use and install.
Key applications
- Remote monitoring of sensitive areas, for example server rooms
- Retail/small business monitoring/security – A business owner or a remotely located security company can monitor the entire store as well as zoom into critical areas such as cash registers
- Remote diagnostics – Engineers based at a head office can troubleshoot errors on remote sites through visual inspection with greater detail
- Remote guidance – A qualified engineer can view live images and control the camera direction over the internet and guide on-site service personnel on remote locations, over the telephone.
Reader Service No 100 (or go to www.security-installer.co.uk/enquiries and key in 100)
Overall assessment
It is probably unwise to make too many direct comparisons between the 2130 and a conventional dome or PTZ camera. The technology does involve a number of trade-offs compared with a conventional CCTV system, the most significant ones being the variable delay, slower frame rates and lack of fine positional control. However, in most other respects the advantages more than outweigh the drawbacks, notably the simplicity of installation (assuming that the somewhat crude and occasionally erratic setup procedures on this model can be improved).Image quality is excellent and totally independent of geographical location. Network operation also means freedom from complex and costly central monitoring, and recording is easily handled by PCs on the network, rather than dedicated tape or disk based devices. It is also a lot easier to manage from anywhere on the network and if you add fast broadband or ISDN Internet connection into the mix there is the facility to remotely control and monitor the camera from just about anywhere.
There is a sense that network cameras are still a work in progress and the Axis 2130 has a few rough edges but it is abundantly clear that this technology is now sufficiently developed for it to be considered not only as an alternative to cabled CCTV in many installations, but also as a valuable new resource in its own right, providing installers and end users with many new and exciting facilities.
Source
Security Installer
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