Potentially outstanding, but still a work in progress
DIGITAL VIDEO RECORDING HAS COME A long way in a short time, clearly illustrated by the proliferation of new systems coming onto the market. However, unlike analogue video tape recorder technology, which was built around common standards and formats and matured relatively slowly over a number of years, there's a sense in some quarters that digital video recording may be moving just a little too quickly.
Time lapse VCRs are complex electro-mechanical devices that require a considerable investment in fabrication and assembly plants. In their heyday it could easily take two or three years for a product to go from initial concept, through stringent testing to a finished product.
But digital video recorders can be built quickly and relatively cheaply using standard off-the-shelf computer components and software. This is no bad thing and computer hardware and software is inherently more flexible, allowing significant changes to be made to the way a product performs and behaves, even after it has reached the marketplace. Broadly speaking this is a benefit, though we have come across several PC-based DVRs that could have done with spending a little more time in the development and testing phase, sorting out bugs and glitches.
It would be unfair to categorise the LJD Leviathan as hurried or cobbled together but there are several aspects of the design that leave an impression that it is still a work in progress, with a few loose ends that could have been tied up before it went into production. Leviathan is a multi-channel DVR based on a desktop or rack-cased PC chassis. Our test model was a four-channel type housed in a 'mini' cube-shaped system unit (8, 12 and 16 camera configurations are also available). Inside the very compact case is a 2GHz Celeron processor, 256Mb of RAM, a 120Gb hard disk drive and a CD-R drive. The operating system is Windows 2000 (Windows XP is apparently also available) and the only non-standard items are a video capture card and LJD's DeltaWave software. Our package also came with Nero Express CD-R 'burning' software.
The feature list is mostly very straightforward and, depending on the chosen set-up parameters, recording times of 30 days or more are possible, after which recorded data is overwritten. It's a triplex system allowing, in theory, simultaneous recording, display and playback, though this is quite difficult to achieve in practice.
Resolution for each channel is set to 768 x 288 pixels by default and depending on the camera type, resolutions of 348 x 288 (low) and 768 x 576 (high) are also possible, though at a cost to definition or the ability to resolve smooth motion. A real-time recording (25 frames per second) mode is available but this is only possible on one camera channel per input card; normally recording rates and compression levels would be set manually to suit the operating conditions.
Leviathan works in a slightly unusual way – it is a continuous, motion-based recording system. All camera channels are monitored but it only records images to hard disk where there is movement between subsequent frames of video data. To make the most efficient use of its storage capacity and avoid recording superfluous data it has a configurable motion mask that can be programmed to ignore movement in specified areas of the picture.
Unlike most other DVRs there are no external contact alarm facilities, which seems like an oversight on an otherwise well-specified multi-camera recording system. It does have an audio recording facility but it is one of those less well developed features mentioned. It's a single channel affair and not tied into any of the camera inputs nor is it synchronised with image data or time-stamped. It can be used as a recording trigger but without any tie-in to the video it is of limited value for event analysis. The main operating manual, which is in the form of several PDF files on the software installation CD-ROM, mentions a loop through facility for one camera input on each capture card, though this didn't appear to be available on our sample. Recordings may be viewed over a network (or the Internet) using the supplied 'client' software. It has a built-in scheduler that can be programmed to activate the system or individual cameras at pre-determined times or send 'alerts' (motion activated recordings, system status reports, image attachments etc) to nominated individuals over a network or by email and SMS text message.
All of the various set-up functions are accessed from a row of tabbed buttons along the top edge of the 'desktop'. The main desktop is neatly presented and easy to use; anyone who knows their way around Windows should have no problem getting to grips with it. In normal attended operation Leviathan's user interface shows all the connected cameras in single or multi-screen format. Views are switched by clicking on a set of camera buttons at the bottom of the screen or a set of multi-screen icons in the bottom right corner of the display. Each camera image has a time/date stamp and editable title. A simple pie-chart display shows the relative amount of free/used space, in days and hours, available on the hard disk.
Recordings are reviewed using a utility called Video Explorer. It gives the appearance of being a separate program running within the main program, which makes it extremely difficult to have both live and recorded images on the screen at the same time. Nevertheless Explorer is one of the more impressive features.
Clicking the Explorer button opens a simple calendar display showing the days on which p.27 recorded data is available. Once a selection has been made Explorer's viewer windows opens with a multi-screen display and a 'timeline' on the left side of the screen. This is made up of a set of vertical bands, one for each camera. The Timeline represents the chosen video 'fragment', which could be a period of days, or a single 24-hour period, with the start and end times and dates shown at the top and bottom. Green areas of the band indicate that a recording has been made, blue shows no activity was recorded and red warns that the camera input was interrupted.
Placing the mouse pointer over any point on the timeline shows a precise time/date readout. The whole fragment can be viewed in real time by clicking the Play button or a shorter segment can be analysed more closely by highlighting a section of the timeline, which then expands or 'zooms' to fill the display. Recordings can be replayed in forward or reverse direction, or frozen, and it has a rudimentary fast search facility though it is difficult to use accurately. Recorded fragments can be 'bookmarked' to make them easy to find though it would have been useful for this to have archival properties to prevent potentially important recordings from being overwritten.
Another handy Explorer feature is Search Motion. This is used to define an area of an image, using the mouse and a set of 'crosshairs'. The software then searches through the fragment looking for any movement in the specified area, creating a sequence of thumbnail images, which can be analysed a frame at a time or strung together to form a video sequence. There is a simple picture zoom and various other tools for enhancing still images and recorded segments, which can be saved or archived and viewed on another PC by exporting to CD-R disk. Once again there's a feeling that this feature hasn't been fully thought through. No attempt has been made to integrate the CD-R function with the main program. Instead each image or video fragment has to be renamed and saved as separate files within Windows and then recorded onto CD-R using the supplied Nero Express program.
And since the images are recorded in a proprietary file format, a viewer program (the remote Client utility) has to be recorded on the disk as well, if the images are to be viewed on any PC other than the one they were recorded on.
It's all a palaver and the operator needs to know his way around Windows and programs like Nero. Exporting recordings for external viewing or archiving is a basic function of a DVR and ideally it should be seamlessly integrated into the main program. The final element in the system is the Remote Client, which allows images to be viewed and recorded locally over a local or wide area network or the Internet. The Client software can also be used to access several monitored sites at the same time. Unfortunately the set-up is not well explained in the manual and will probably take a network-savvy manager to fathom. In spite of the components being loosely integrated, video performance is among the best we have seen on a PC-based DVR. Live display and playback resolution is very close to the manufacturer's claims. There is negligible picture noise and good colour accuracy. Using the supplied tools it is possible to get very sharp stills and the zoom facility does a fair job of enlarging details, without the image becoming too soft or pixellated.
However, the star is the timeline based search utility. This is something we have been campaigning for on DVRs since Day One because it greatly simplifies the task of finding and reviewing recorded segments on a non-linear recording medium like a hard disk drive.
It's highly intuitive and easy to use. The only small disappointment is that it would have been even more useful if the system had any external alarm facilities, so that event flags could be shown alongside the video timeline.
Although the timeline reduces the workload significantly it still needs a decent set of picture search facilities, but these should be relatively simple to incorporate into the Explorer programme's playback controls.
What the manufacturer says ...
The leviathan DVR has proved to be our flagship product. Using our unique Delta Wave compression, it generates the smallest digital data footprint of all current DVR units. This makes the data small enough to effectively transmit video images even over a 56k modem connection. The compact size of the Leviathan 8 means it can be stored safely and neatly in a location where space is very limited.
The backbone of the system is a Windows 2000 operating system which accommodates secure and easy network dial-in configuration. Fitted with a CDRW as standard, with the option of a DVD-RW, data extraction is very easy.
Each camera can be configured for: frame rate, frame compression, time of recording, detection area, alarm and remote viewable (by way of covert) option. Remote access is easily achieved using our remote client software, allowing up to 10 remote users simultaneously, and full privilege configuration.
The system is delivered pre-installed and pre-configured, and simple installation is the key to its already phenomenal success. With sales in excess of 2,000 units last year, take up of new technology within the CCTV industry would appear to be at an all-time high. The Leviathan can be seen at all the Security Roadshows, where our staff will be happy to show its full capabilities.
LJD Digital will continue to develop the Leviathan range and our R & D team is looking into ever more innovative additions to the product. We look forward to announcing them over the coming months.
Overall assessment
The most obvious shortcoming is the way still images and video segments are exported to CD-R. It shouldn’t be too difficult to blend this facility into one of the program’s menus, along with automatically putting a copy of the viewer utility onto the disk at the same time.Video Explorer is a major improvement on the viewer facilities we have seen on many rival PC-based DVRs. And the timeline gives the user a very clear and easy to understand graphical representation of what has been recorded, but again it doesn’t seem to be bound in with the rest of the software.
We are always pleased to see audio recording on a DVR but without some sort of synchronisation with the video data it doesn’t do much and it is a wasted opportunity.
Several quite important features are notable by their absence. Where are the video loop-throughs and analogue monitor output and why hasn’t it got any external alarm inputs?
Automatic overwriting of recorded data could be a potential problem too: the pie-chart graphic showing the time used/ remaining is obviously welcome but apart from saving data manually, there is no way to protect data from being erased.
The facility to do so may already be there and it might be possible to modify the bookmark utility to prevent marked segments from being inadvertently deleted.
The Leviathan system shows a great deal of promise but we feel that it is let down by a lack of coordination in the way some of the software components operate and are presented.
However, as it is largely a software-based device nothing is fixed in stone. We hope the designers give some though to fine-tuning what could be an outstanding product.
Source
Security Installer
Postscript
Reader Service No 101 (or go to www.security-installer.co.uk/enquiries and type 101)
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