Bid adieu to analog surveillance systems
Zatni Arbi, Columnist, Jakarta, firstname.lastname@example.org
Last week, a report in The Jakarta Post revealed the surveillance system at the Soekarno-Hatta International Airport failed to provide any video recording that might have helped the police in their investigation into the cruel, heartless and senseless bomb attack there on April 27. It was not really a piece of surprising news in this country, where new equipment is bought all the time but budgets for maintenance and repair are never available.
Without a recording capability, there is not much we can expect from surveillance cameras, although we may have hundreds of them all over the terminal building. It is simply not humanly possible for the security personnel to stare at the monitor screen to watch for any possible criminal act -- including planting a bomb that will maim completely innocent victims -- for 24 hours a day, seven days a week. Usually, it is the recording that helps lead investigators to the perpetrators.
If you watch John Bunnell's World's Wildest Police Videos as regularly as I do, you will have realized how powerful good surveillance cameras can be. However, without the recording capability, they will be nothing more than just expensive items to be added to the company's budget. They may deter would-be criminals, but they will be totally useless after the fact.
* Analog vs. Digital
The biggest challenge in surveillance recording is the video storage. The old analog system uses video recorders to put the recordings on tapes. These VCRs, needless to say, need a lot of maintenance. Also, we cannot recycle the same tape over and over, as the quality will degrade over time.
It just so happens that a few weeks ago I was able to play around with a PC-based surveillance system courtesy of Chateau Technical Corp., the distributor of Taiwanese Chateau digital video surveillance system. Being PC-based, the system was digital rather than analog. The video camera the company lent me was an ordinary analog one, but the VG4C XP card that came with the system converted the analog video input into digital data, compressed it with the company's proprietary technology called SMICT, and saved the time -- and date -- stamped file on the hard disk.
The video compression capability is one of the main advantages of any digital system as opposed to an analog recording system. The compression, which worked in a similar way with the MPEG method used in VCDs, records only the changes in the captured frames and discards the areas within the frame that do not change over time. Suryadi Tjandrasa, the company's technical manager, told me the SMICT compression technique would add a maximum of two to three Megabytes (MB) to the video file per minute. "The increase in the file size will be minimal if there is no movement recorded, as there is no difference in the frames over time," he explained.
* The cards
Every VG4C XP card has four ports to accept the input from four separate analog cameras. We can install up to four cards in a single PC, which enables us to access sixteen cameras simultaneously. Frankly, though, it is hard for me to imagine being able to scan all of them at the same time, even when I use a large 20-inch computer monitor. But, again, it is the recording that is more important. The card also has two audio-in jacks, so we can record audio in addition to video.
The US$700 card that I tested is the midrange one. It is capable of capturing and recording video at the minimum rate of 15 frames per second (fps) with all four cameras actively feeding their signals. At this rate, the video is a bit jerky, but still acceptable for use as court evidence. When only two cameras are used, the rate will increase to a very smooth 30 fps -- its maximum capability.
The low-end, $550 VG4C Plus also has four video input jacks and two audio RCA jacks. The frame rate is below 10 fps, which is still useful for criminal investigations. However, the high-end, $1,000 VG4C RT can give us 30 fps regardless of whether we use one camera or sixteen cameras. The RT in fact stands for "real time". The card was demonstrated to me when I visited the company's showroom, and there was basically no jerkiness noticeable in the four panes on the screen.
Suryadi told me the minimum requirements for the PC were a Pentium 4 processor running at least at the speed of 1.8 GHz, 256 MB of RAM, a fast hard disk and Windows 2000 or Windows XP. A good graphic card -- at least the GeForce MX Series with 64 MB of memory is recommended for high-quality video playback. The video resolution is 640x480 pixels in NTSC or 704x576 in PAL. My test system had a fast 60 GB IDE Maxtor. "I/O speed is very important, as the card has to continuously write to the hard disk," he said.
* Remote access
The video images from the cameras are displayed on the screen and recorded on the hard disk simultaneously. The videos are recorded in separate files, which are very simple to retrieve and play back.
Because the system is digital, a lot of things can be done with the videos in addition to storing them on the hard disk. First, the system can be accessed remotely using IP addresses- through LAN, even through the Internet. Of course, the quality of the images displayed on the remote screen will depend on the bandwidth of the connection. But, at least, this system enables us to monitor our home from our office, for example. Or, if you want to play Big Brother, you can monitor whether your employees are indeed working at their desks instead of chatting in the alleys when you are in a different location with your notebook computer and Internet access.
One of the more interesting things that I have learned was the system's motion detection capability. We could add an unlimited number of masks to the displayed image, much like we do before we apply a certain effect to an image in Photoshop or CorelPHOTO- PAINT. The software will then pay special attention to the areas inside these masks. When there is a change to any of them, it will then automatically take a series of snapshots at an interval of around two seconds and take one or more actions that we have predefined.
So, for example, if we have placed a mask on the image of a closed door on the screen, when the door opens the automatic snapshots taken will be triggered. The system, for instance, can trigger a siren, dial our phone number, send e-mail with a preset number of snapshots to multiple e-mail addresses, etc.
The system also allows us to control PTZ-capable surveillance cameras remotely. These are cameras that can turn to the left, right, up, down, refocus and zoom in or out upon our commands. PTZ actually stands for pan, tilt and zoom.
The big question will be what happens when the hard disk is full? The system has the intelligence to recycle the space by overwriting the oldest recording. Another unique feature of the Chateau products are the Watchdog, which will automatically reboot the computer when the system crashes. This ensures minimal disruption in surveillance recording without requiring human intervention.
Chateau is certainly not the only game in town. At the recent 6th Annual International Security Technology Exhibition in Taipei, for example, around 90 exhibitors showcased their digital surveillance products and services. In fact, Taiwan has come to be known as the source of all kinds of cameras, including hidden spy cameras that have made some ladies feel increasingly insecure lately. But, if you are looking for a legitimate surveillance solution, you should really take a look at Chateau's line of products. And, definitely, it is time you move from analog to digital surveillance.