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What our experts say …

It’s hard to imagine the circumstances that might threaten the well-being of a Pelco DX8000 digital video recorder; suffice it to say that it appears to be bullet proof and built to withstand just about any natural or man-made hazard.

It is one of the most impressive examples of engineering that we have seen for some time, and this is well illustrated by the fact that at a time when most new DVRs weigh in at between five to 10kg, this one tips the scales at just under 20kg!

However, its formidable physical attributes are overshadowed by the technical specification, which puts it at or very close to the top of the pile, so we’ll begin with a brief run-down of its more notable features.

These include a maximum resolution of up to 720 x 576 pixels and a top recording rate of up to 400 images per second (352 x 288 pixels, in PAL mode). Our test sample (the DX8016-080) was equipped with 16 camera inputs (eight camera versions are also available) and it comes with an 80Gb hard drive, expandable up to 1 terabyte.

Depending on the number of cameras connected, the chosen resolution, compression and frame rate settings, recording times may be measured in weeks or months.

Images can be backed up and exported to optical disc using the built-in CD-RW drive, and it has an extensive set of networking capabilities – more on those later – with the facility to send images and alerts, via a network or the internet, to remote PCs and handheld devices.

It’s a full duplex design providing simultaneous playback and recording, and there are multiple display options plus highly effective digital zoom, motion detection, alarm and scheduled recording modes.

It has advanced on-screen PTZ control and programming (Pelco P, D, and Coaxitron protocols) and it is well protected against accidental or deliberate interference by an array of hardware and software security features.

Audio recording on DVRs has been a bit of a hobbyhorse of ours for some time, and even now it is a comparatively rare feature, but the DX8000 sets a new standard with 16 recording channels, one for each camera input.

Inside the super-tough heavy-gauge steel case there’s a fairly conventional PC set-up, comprising an Asus motherboard with a 2.8GHz Pentium 4 CPU and 256Mb of RAM.

It’s a large and noisy beast, with six cooling fans dotted around the case and inside the power supply module; these create quite a roar, and the vast rack-mountable case makes an effective sounding board, so it would be fairly noticeable in quiet surroundings – but on the plus side, this also means there’s plenty of room inside the case for expansion, and our sample had four vacant hard drive bays.

On the back panel there is a familiar line up of connectors on the rear of the motherboard for a PC monitor, keyboard, and mouse, plus the usual USB, audio, parallel and serial ports and local area network (LAN) socket.

There is a bank of 32 BNC sockets – 16 for the camera inputs, and another 16 for automatically terminated loop-throughs. Connections for an external video monitor, RJ-45 sockets for dome and PTZ camera telemetry and audio inputs are mounted on plug-in expansion cards.

A D-Sub break-out cable for the audio connections is supplied, along with plug connectors for the alarm terminals. A large fan vent and a key-lockable drop-down door that opens to reveal the main power on switch dominate the front panel; there’s a pair of USB sockets, status indicator LEDs and the CD-RW drive-loading tray.

Setup and operation
The DX8000 uses the Windows 2000 Professional operating system, which has a good reputation for stability. Following boot up (or a power interruption), the Pelco application launches automatically and begins recording.

The main desktop opens in ‘live’ mode with the connected cameras shown in the preferred display format, plus a set of controls and displays for recording and playback.

The latter can only be accessed when the operator has logged in with a user name and password. The desktop can be configured to show or hide the controls and a PTZ panel can provide larger camera views.

Unlike some of the PC-based DVRs we have seen in the past few years, Pelco appears to have devoted a considerable amount of time and effort into making it as user-friendly as possible, with an exceptionally easy to navigate timeline display, clearly showing recording progress, alarm events and motion detection in colour-coded blocks. A second bar graph indicates disc usage, and total time recorded is shown in a small status panel.

To review a recording, a camera is selected from a list on the left of the screen and the mouse is used to move a cursor superimposed on the timeline. Alternatively, specific times and dates can be selected using up-down arrows or keyboard entry.

The timescale can be easily expanded using a pair of +/- buttons for more precise location of times or events. Playback controls provide freeze-frame, step frame, reverse play and variable forward and reverse search and slow-mo.

Any part of the image can be digitally enlarged using the mouse cursor to define the area of interest.

In addition to the basic manual recording review options, the DX8000 has a sophisticated ‘search’ facility, accessed by clicking the camera icon on the toolbar.

There are three methods: Index Search, which generates a list of alarm and motion activated events; Thumbnail Search, which displays the first image from the start of each new recording; and Pixel Search, where the operator specifies an area of interest in a recording and the system displays all of the images recorded in the past 24 hours where movement has occurred in the selected area.

Clicking the Tools icon on the Toolbar brings up a range of set-up and configuration menus, selected from a row of icons down the right side of the screen. The opening display is used to set the camera name and display system information.

There are also controls for brightness, contrast, saturation, hue – individually adjustable for each camera input – and a sub-screen for configuring the motion detection system.

The size of the sensor matrix grid is variable and set using a slider control, from 10 x 10 to 40 x 40. Up to five separate ‘zones’ can be assigned to each camera channel, and a second slider control sets the sensitivity.

It took us a little while to work out why the motion detection system didn’t work on our sample. The solution wasn’t immediately obvious from the manuals, but a call to the experts at Pelco quickly resolved the problem, revealing that for some odd reason motion detection has to be enabled on a separate menu, as a scheduled task.

Menu screen two covers the alarm and relay settings for each camera channel, which includes linking motion detection to multiple camera recording, PTZ positioning and relay outputs.

The third menu deals with recording schedules, and again there are enough options to satisfy just about any requirement, enabling any camera to be set to record at predetermined times and dates, or in response to alarm activation.

This menu also contains the elusive settings for enabling motion detection, as well as resolution, recording quality, frame rate and pre- and post-activation recording times, none of which are particularly well signposted in the paper and online documentation.

Network configuration is dealt with on menu four, and menu five handles the back-up options, to an internal CD-RW or DVD-RW drive, or an external tape or network drive.

Recordings can be exported in the unit’s native recording format or one of a range of common still and video formats, including AVI, ASF, BMP, JPEG or TIF. The recorded disc helpfully includes a viewer utility, so a recording or still image can be displayed on just about any PC.

The remaining menus are devoted to local and site administration (specifying users and groups), system configuration, setting up email notification and the external video monitor display.

The logged-on operator can exit to Windows at any time, to carry out adjustments to the PC’s set-up menus and to install external hardware, such as a printer, or to access online manuals and documentation.

The networking facilities mentioned briefly a moment ago cover a lot of ground and they include support for up to five client PCs and interconnection of multiple DX8000s, fed by up to 80 cameras, which can be administered and controlled from a networked or web-connected workstation.

Client PC set-up, for remote viewing and administration, is facilitated with a set-up disc. This also includes software for installing the DX8000 viewer, plus web PC and mobile PDA clients. The latter operates under Microsoft PocketPC 2002 or later. In most cases, setting up client PCs should be fairly straightforward, but installers would do well to make sure their networking skills are up to date.

Performance
We’ve come to expect superior recording quality from DVRs – compared with tape-based surveillance recorders – but the DX8000 raises the bar even higher.

On a monitor connected to the unit, with image quality set to ‘high’ or ‘best’, resolution is excellent and more than capable of doing justice to the best of today’s top-end colour cameras, capturing (and reproducing) plenty of fine detail. Contrast and colour fidelity are also a notch up on many rival DVRs and picture noise is at a very low level.

Playback control is another area where the DX8000 excels, and the ability to rapidly locate events from the timeline or search menus puts many rival DVRs in the shade.

Reviewing recordings in fast search mode and slow-mo is another major plus point that convincingly demonstrates the benefit of hard disc recording over tape-based video recorders.

The only small disappointment – as far as image quality is concerned – is the marked drop in resolution in video files exported to disc (in AVI format). These also suffered from an increase in digital noise and could look quite blocky when there was a lot of movement in the scene.

Video quality can also suffer over a network or an internet connection, though much will depend on the available bandwidth and infrastructure.

Audio recording is the icing on the cake. As we’ve said, it’s a frustratingly rare feature on the current generation of DVRs, so Pelco are to be congratulated for taking it to its logical conclusion with separate high-quality recording channels for each camera input.

What the manufacturer says ...

The DX8000 Series Digital Video Recorder represents the next generation of high-performance, PC-based digital video recorders.

It is designed for those users who demand an easy-to-operate, yet innovative DVR. The DX8000 features built-in video motion detection, alarm-based recording, and relay output controls. Models range from an eight-channel, single 80GB HDD unit to a sixteen channel unit with up to 1TB of storage.

Fully implemented networking capabilities allow remote administration, playback, and export using the included PC client application.

Live viewing is supported on a variety of client platforms, including internet browsers and Pocket PC-compatible handheld devices.

Versatile high-speed search operations include time and date, event list, thumbnail, and intelligent pixel searching. Extensive scheduling features allow customizing of weekday, weekend, and special event recording.

The DX8000 offers users a highly intuitive and ergonomically designed interface that provides simple and efficient access to all set-up and operations functions. Manual backup can be performed using a number of optical, magnetic, and mapped network drive options.

Overall, the DX8000 combines a feature-rich security platform with a flexible and intuitive user interface offering an unprecedented level of functionality.

Features include up to 720 x 480 recording resolution, up to 400 images per second recording rate at 352 x 288 resolution (PAL), up to 16 camera inputs and outputs with auto termination, a maximum internal storage capacity of 1TB, multiple displays for live viewing or playback, and continuous motion detection, alarm, and scheduled recording.

The DVR has the ability to connect multiple DX8000s together, and is able to support five simultaneous clients. It includes network bandwidth throttling, on-screen PTZ control, up to 16 channels of audio recording (optional), remote PC, web, and handheld client software, proprietary compression technology offering high-quality and small file sizes, and security and lockdown protection.