May 1, 2003 12:00 PM
Closed-circuit television (CCTV) may soon rid itself of wires. From remote camera locations to monitoring stations, the aim is to broadcast video signals to remote locations virtually anywhere.
A handful of companies have recently entered the emerging security field of broadcast CCTV. One system comes from Sequent Technologies Inc., City of Industry, Calif. According to company spokesperson Brett Hunt, Sequent has installed a broadcast system at a large infrastructure facility.
Sequent's television-quality video transmitter can broadcast streaming video from a camera over satellite, cellular, wireless LAN, or other kinds of networks. During an emergency, authorized individuals in any location can call up video from the transmitter with a desktop computer, laptop, cell-phone or PDA.
The transmitter can also send audio signals, and a camera site equipped with audio technology, such as a public address system, will enable authorities to communicate with people at the site during an emergency.
Broadcast video surveillance, once tested, could provide law enforcement, public safety, Homeland defense and military agencies immediate access to intelligence. By broadcasting on-the-spot information, the technology could accelerate emergency responses and facilitate the best possible decisions.
The Sequent technology is available in three configurations.
First, a cigar-box-sized transmitter and computer, called the Ranger 350i, houses a 96gb hard drive that can record 8,000 hours of surveillance video or 48 hours of digital broadcast quality video. The Ranger 350i operates in mobile or fixed installations.
A second model, the Ranger 650 HES, has been designed for fixed installations in various harsh environments, including underwater.
A third Sequent device, called the Paladin Quattro, is designed to function as an enhanced digital video recorder in sensitive CCTV installations. The Paladin combines four Ranger 350i sensors and can control up to 32 cameras from a security center rack. The Paladin operates like a wired digital video recorder, but adds wireless transmission capabilities as well as a year's worth of video storage capacity.
Paladins use fixed power sources, but Rangers operate on AC, DC, automotive or aircraft power. All models are compatible with several operating systems, including Linux and Microsoft Windows.
As a law enforcement tool, the system could, for example, enable police officers to broadcast video during high-speed chases. Supervisors at headquarters would be able to monitor the chase and make informed decisions about how to proceed. During a chase, the system could record video as well as times, speedometer readings, and locations ¡ª thanks to a built-in global positioning system.
Broadcast video can also function in public safety applications. A system monitoring railroad crossings would enable engineers to preview crossings from the locomotive and take appropriate action if someone or something is blocking the tracks.
Anti-terrorism applications include remote monitoring of dams, bridges, airports, nuclear power plants and other sensitive infrastructure locations. When necessary, the portable Ranger can be moved to other camera sites with ease. During an emergency, additional systems installed in helicopters and aircraft can provide broadcast video from various camera angles.
There are two appropriate applications for broadcast video surveillance. The first involves camera sites where hardwiring is impossible ¡ª police cars, trains, ships, and airplanes. The second involves emergencies at camera sites that might require cooperation among authorities from other jurisdictions. For example, an event at a nuclear power plant would likely concern a host of local, state and federal agencies at numerous locations across the country, as well as first-responders on the scene.
In either application, Sequent's back-end software, RAIDIUS, enables users in various locations to interact with other viewers while monitoring video broadcast by a Ranger-based video system. No special software is necessary, as observers with password access to the video network can monitor video with conventional media software and browsers while communicating by telephone.
There are two key differences between Sequent's technologies and other wireless video surveillance concepts, Hunt says.
First, Sequent technology delivers streaming video with synchronized audio and meta-data (such as the date and time). Competing systems use motion JPEG or Wavelet "push" technology, which provides a series of photographs from the video camera source. Called Serial Still Frame (SSF), this technology cannot synchronize audio and other data with video.
Second, the bandwidths required by SSF technology slow transmissions. With SSF, each individual picture must be separately encoded, recorded and transmitted. The Ranger 350i compares the pixels in successive video frames and transmits only those that have changed. "Our MPEG 4 derivative compression technology allows us to combine data into five-minute chunks," Hunt says. "The system sends one chunk after another. This means you can use low-speed transmission systems such as DSL lines."
In effect, the computer, PDA, or other device receiving this data can display the first five-minute chunk of video while the next five-minute chunk is coming in. "Competitors would need a T3 line or maybe several hooked together to match our transmission capabilities," Hunt says.