The Change in Digital Video Surveillance

No section of the physical security market is going through as much technological change and structural redefinition as video imaging and storage. The concept of what has been called CCTV is being redefined to address new requirements for speed and...


No section of the physical security market is going through as much technological change and structural redefinition as video imaging and storage. The concept of what has been called CCTV is being redefined to address new requirements for speed and first response to dangers never before perceived. This technological transition will have a powerful impact on how video is obtained, stored and used.

From Detection to Prevention
In 1997, an article in an ACLU newsletter contrasted the use of video surveillance in the U.K. and the U.S. It stated that the threat of bombs and terrorism in the U.K. made necessary heavy surveillance of public areas, but the absence of such threats in the U.S. meant that our use of surveillance was inappropriate-we used this powerful tool to "fight people who 'spin doughnuts' with their cars, 'loiter' or commit 'nuisance crimes.'" My, how the world has changed. The realities of terror have drastically altered our uses for video surveillance and the number and scope of installations.

Before 2001, camera systems were used primarily to catch the bad guys after a crime had been committed. If you had a very large, well-trained security team, you might even be able to catch them in the act. The list below defines the primary uses of camera systems before the new reality.

  • Catch perpetrators
  • Protect assets
  • Watch workers
  • Protect from litigation
  • Stop cheating in gaming applications
  • Monitor traffic
  • Watch the perimeter
  • The gaming industry was the primary driver of video technology and its most proactive user, with traffic monitoring and control a close second. Although the main drivers of usage are still in gaming and traffic, protection of public spaces and high-occupancy facilities has now taken the use of video to a new level. The end user's perceived needs for video surveillance are heavily weighted toward security and life safety issues, with asset tracking and manufacturing observation as significant secondary requirements. Most video applications have now begun to take a proactive slant, and this has slightly changed our list of primary uses for video:

    • Protect from and catch perpetrators
    • Protect and track assets
    • Watch workers/P.O.S. integration
    • Protect from litigation
    • Stop cheating in gaming applications/Recognition and tracking
    • Monitor roadways, airports, seaports and all vessels of transport
    • Watch the perimeter

    The burgeoning use of video for protection and prevention has forced the development and use of new ways to obtain images, store them and access the data from remote locations.

    The Growth of Digital
    In large installations that require high-quality, fast frame-rate images to be stored for long periods of time-the types of installations that are becoming more common with the growth of proactive security-videotape is neither cost effective nor easily searchable. Digital systems allow users to easily access specific images and send them across a network, and these systems require less maintenance expense than analog videotape systems. It's easy to see why the change to digital has been happening at almost revolutionary speeds.

    The J. P. Freeman 2003 Worldwide CCTV & Digital Video Surveillance Market report projects a decrease of 70 percent in conventional analog recording by 2007, which would decrease its share of the market to 22 percent. The same report projects a 289 percent increase in digital recording in the next three years, which would give it 78 percent of the market. I think you call that a paradigm shift.

    So one of the hot buttons for the past three years has been analog to digital. Although most current CCTV cameras do output an NTSC or PAL analog signal, the imaging is done with a CCD or CMOS digital chip that is then run through a processor to define the image/picture/frame. This is then sent through a digital-to-analog chip to output the NTSC or PAL image. The analog signal must be converted back to a digital image in order to be stored on a digital medium such as a hard drive or CD.

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