From analog to digital recording, today’s video surveillance technology moves to a new level of sophistication - the IP network.
Enterprising Analog
The 1970s ushered in a growing popularity of CCTV systems with analog recording for security and surveillance applications in commercial buildings. Introduced to the private sector in the 1960s, CCTV was used in hospitals, 24-hour convenience stores, and other commercial locations by the 1970s. At this time, technology was relegated to passive recording of events, with little or no means for active monitoring.
By the mid-1980s, analog video recorders (VCRs) and camcorder technology had revolutionized the way facilities managers and security teams kept tabs on building activity. They now had a record of all surveillance activities, stored in a library of videocassette tapes that could be rewound, reviewed, and replayed.
These early systems had massive limitations. The old tube cameras recorded visibly only in the daylight. The VCR could, at most, store only about 8 hours of footage and record from only one camera at a time. To top it off, videocassettes were - and still are - bulky and hard to store.
According to industry analyst JP Freeman & Co., there are still more than 20 million analog cameras installed in the United States. It’s a technology that has worked for more than 20 years, but newer, digital technology is beginning to edge it out.
A Digital Revolution
Enter the mid-1990s and the advent of the multiplexer - a unit that allows recording on up to 16 cameras simultaneously, making it possible to cover the entire facility with a single system and features such as time-lapse and motion-only recording. It also reduced the number of tapes needed to provide a historical record of facility monitoring.
“It was still in the analog format, but you could connect the cameras and monitors to it and automatically or manually switch from one camera to another,” notes Jeff Kiuchi, a product specialist at Mitsubishi Digital Electronics America Security Products in Irvine, CA. “It could provide long-term recording for 16 cameras and be saved in regular tape format. To this day, it’s still in use.”
However, as Kiuchi and other industry experts and analysts note, the use of analog technology is spiraling downward due to digital clarity.
The mid-1990s also marked the introduction of the first digital video recorders (DVRs). The technology was limited, Kiuchi notes. “Today we have 300- to 500-gigabyte hard drives,” he says. “Back then, it was only in megabytes. Crashes were inevitable.”
With the advancement of hard drives and video compression technology, DVRs rapidly became more attractive and, within the past 3 to 4 years, have become, as Kiuchi puts it, quite “en vogue.”
According to statistics from analysts Frost & Sullivan and JP Freeman & Co., 2002 marked the point when digital technology surpassed analog recording in terms of demand. “Digital is all over the place now,” Kiuchi says. “You can get an amazing amount of storage.”
Besides storage capabilities, there are many advantages to digital recording over analog, including easy playback and search capabilities, recording flexibility, a single recording unit, easy duplication and file sharing, long-term recording, and remote monitoring.
What’s Next?
In the short term, digital recording’s future lies in networking and Internet protocol (IP)-based surveillance using network cameras. Network cameras are connected directly to an IP-based network, integrating to applications on the network. This enables users to have cameras at remote locations and to view, store, and analyze live video at another location.
Simply put, use of IP networking to control video surveillance means footage can be shared anywhere the network reaches, eliminating the need for a central surveillance booth. It also provides managers with multiple options for storage and retrieval of archived video data, including redundant off-site storage.
“Network cameras have emerged as the fastest-growing product category, providing a clear indicator that IP-based systems are poised to take over,” Fredrik Nilsson (of Chelmsford, MA-based Axis Communications U.S. Inc.) writes in The Top 10 Myths about Network Video white paper. “Because of its scalability, among other advantages, IP surveillance is an established, attractive technology not only for enhancing or revitalizing existing surveillance and remote-monitoring applications, but for a vast number of new applications in vertical markets.”
Robin Suttell ([email protected]), based in Cleveland, is contributing editor at Buildings magazine. Additional sources included BroadWare Technologies Inc. and the California Research Bureau.
