Read an Excerpt
Digital Video Surveillance and Security
By Anthony C. Caputo
Butterworth-Heinemann
Copyright © 2010 Anthony C. Caputo
All right reserved.
ISBN: 978-0-08-096169-9
Chapter One
Introduction to Digital Video Security
Introduction
Visual surveillance began in the late nineteenth century to assist prison officials in the discovery of escape methods. It wasn't until the mid-twentieth century that surveillance expanded to include the security of property and people. The astronomical cost of these first security camera systems, based on traditional silver-based photographic cameras and film, limited their use to government buildings, banks, and casinos. If questionable activity was discovered, the monitoring security firm would develop the films in a secure, private darkroom laboratory to analyze at a later date. Live television was occasionally used during special events to monitor a crowd, but law enforcement was usually limited to the television studio to view the multiple cameras.
The theory behind visual surveillance was founded on the same four key factors that are still prevalent today. These are
1. Deterrence
2. Efficiency
3. Capable guardian
4. Detection
Deterrence
If potential criminals are aware of the possibility of being watched and recorded, they may determine that the risk of detection far outweighs the benefits. Visual surveillance as a deterrent is used from casinos to retail settings to public transportation. Countries all over the world use video surveillance, focusing its use mostly on public transportation (planes, trains, and autos) and select public areas. Based on an Urban Eye study (www.urbaneye.net), 86% of these international installations are for the prevention and detection of theft, and 39% also serve as a deterrent of violent crime. The amount of crime prevented by using video surveillance is based on the environment and whether the system is solely passive, active, or both. A passive system uses video recordings after an incident to help solve a crime. An active system is monitored by security personnel who are dispatched at a moment's notice. Historically, the most effective crime prevention video surveillance systems do more than record crime in the background. One dramatic example is Chicago's Farragut High School, a public school notorious for its major acts of violence, locker thefts, and vandalism, all of which nearly disappeared within a year after the installation of a closed circuit television (CCTV) surveillance system. Many American cities have likewise seen a reduction in crime due to the addition of a video surveillance implementation and strategy.
In a recent UK Home Office Research Study on the effectiveness of video surveillance as a crime deterrent, 46 surveys were done within public areas and public housing in the United States and the United Kingdom. Of the 46 studies, only 22 had enough valid data to be deemed acceptable for publication. All 22 published surveys showed significant reduction (as much as 50%) in burglaries, vehicle theft, and violent crimes (see detailed report at www.homeoffice.gov.uk). However, it's rather difficult to analyze data on the effectiveness of video surveillance systems due to the many variables in the complexity of the areas of coverage and general displacement. For example, the decrease of crime within an area monitored by video surveillance cameras may have forced criminals to move to a different location, thus displacing the violent crimes. Enclosed areas of coverage — such as parking garages and lots, buildings, and campuses — have better success with video surveillance than large outdoor areas as long as there's a clear presence of a "capable guardian," which can be increased police or security guards or the electronic eyes of security cameras.
Efficiency
Reviewing video surveillance footage at the same time as watching live surveillance provides additional information about a situation, allowing users to make better decisions about deploying the right kinds and numbers of resources. Depending on the number of security cameras and their location, this simultaneous viewing of live and archived video can confirm a sleight of hand or any illegal activity before a patron, customer, or suspect is approached by a security force. In 2007, the Dallas, Texas, Police Department used video footage from 559 incidents to assist in 159 arrests. Their experience indicated that a single police officer monitoring live and archived video can cover far more area than a field officer, including usable image captures of license plates from 300 yards away.
Capable Guardian
In the article "Social Change and Crime Rate Trends: A Routine Activity Approach" by Lawrence Cohen and Marcus Felson (American Sociological Review), the authors suggest that crime prevention includes the presence of a "capable" supervising guardian. That guardian doesn't have to be present, just watching. Today, the guardian doesn't even have to be watching, just archiving using smarter technology. Current video surveillance includes sophisticated video analytics software with the capability of monitoring areas for programmable situations (e.g., bookmark all red automobiles) such as abandoned cars or backpacks, circling vehicles, or even specific license plates. Video analytics can upgrade an originally passive security system into an active one. This introduces the capable guardian by giving the passive surveillance system a "brain" and allowing it to be more responsive to potential criminal activity.
Detection
Detection is the higher profile success factor, providing tangible evidence that video surveillance works. Britain is well known for its video surveillance system, providing law enforcement with the ability to follow anyone throughout the city of London through the use of over 200,000 cameras (with over 4 million cameras throughout the country). This system helped locate four London-born terrorists including the well-publicized CCTV images of suicide bomber Hasib Hussain. Likewise, the arrests of Jon Venables and Robert Thompson in the high-profile British murder case of James Bulger were directly linked to images reviewed on the surveillance system. Furthermore, Scotland Yard convicted 500 criminals using their CCTV database that included 3 years of data on 7000 offenders.
Closed Circuit Television
CCTV, which uses traditional radio frequency (RF) technology, rather than photographic technology, was introduced in the 1980s and provided a more cost-effective and real-time method of video surveillance.
Today's concept of video surveillance has its roots in the analog world of television. The framework of CCTV is a simple one, using the same analog signal you'd receive from your old pre-digital television. A single camera monitors one place and sends it to a CRT television monitor at another place using a coaxial cable. Usually the system has a single command center where security personnel watch black-and-white and/or color monitors of various cameras. Multiplexing technology provided the ability to watch more than one camera on a single monitor, or automate a cycling of various camera feeds on a single monitor to expand the area of coverage. While it's true that many security professionals and companies still use CCTV and the concept of a centralized "command center," not everyone has the space, money, and/or resources for such a system. The idea of wiring a house, office, building, or campus with coax cables from every camera to a control unit and then to each CRT monitor is costly, time-consuming, and thanks to internetworking technologies, unnecessary.
Figure 1-1 depicts an example of a CCTV installation that monitors select areas of coverage. The first installation was designed and developed for the separate parking facility. This implementation included several fixed position cameras on each floor of the parking garage, stairwells, and exits, all connected directly to a primary control unit (PCU) for management of each video stream. The PCU is a simple device for managing the input and output of video feeds through the coax cables. Ancillary utilities and devices can provide simple integration of some alarms, but this technology has limited capabilities and a complex integration process.
A single monitor in the parking garage management office was connected to the output for monitoring cameras. The PCU offered shuffling of each camera feed and select intervals and a keyboard to input the call number for each camera, or the ability to scroll through each camera one by one.
Several years later the campus was expanded; unfortunately the previous CCTV installation wasn't designed to extend the system into other buildings. An underground site survey uncovered various fiber, Ethernet, and power connectivity, but the conduit was either full or damaged over time. Feeding new runs of coax required trenching and/or boring to replace poor conduit runs between said buildings, thus the plan to run coax cables (for video) between the parking facility and the main building was abandoned due to cost. Another isolated CCTV system was designed and developed within the main building. These cameras were installed inside loading docks, exits and entrances, main entrances, and service corridors. A new model camera was introduced into this system that required more connectivity than coax cables for video. Many pan-tilt-zoom (PTZ) cameras were installed, requiring separate wiring interconnectivity with the new PCU for camera controls using a proprietary protocol.
In addition to this phase of the expansion, a primary command center was built to house a new security office with a CCTV control console for several CRT monitors to view the cameras and a new model keyboard with a built-in joystick to access and control the new PTZ cameras.
The main building didn't have any existing conduit or spare conduit pathways to run coax throughout it and into the new buildings on campus. Video Balun transceivers were used to transfer the coax video signal to existing telephone twisted-pair wires between locations, as each building was interconnected to each telephone interim distribution facility (IDF), or a secured closet with twisted-pair terminals for the telephones and a network switch for the computers. The plain old telephone service (POTS) lines were linked into each IDF, the main distribution facility (MDF), the command center, and any room with a telephone. Although the use of Balun can affect the video quality, it made possible the installation of dozens of cameras that were originally deemed too costly.
Multiple monitors were installed within the new command center with a single monitor assigned to alarm displays. Once any alarm system integrated into the PCU was activated, the nearest camera to that location would be displayed on that particular monitor. The chance that the fixed camera would be pointed in the direction of the incident depends on the initial requirements for area of coverage. If there are three select emergency exits, panic alarms, or door sensors, a single fixed camera can only watch one. This creates a one in three chance of catching a specific incident on video (either live or recorded). The command center also included a computer designated for filing incident reports online. These can be accessed by management personnel at a later date from a database via the computer network.
Big Brother Is in the Restroom
Twenty-five years ago general and business communications were primarily synchronous. To accomplish almost anything there needed to be someone on the other side of the table or telephone line, especially when dealing with national and international business. The same holds true for security and video surveillance. Typically, CCTV is most effective as an active system with a security guard monitoring the corridors with someone else, somewhere, watching video surveillance monitors for support. Everything is synchronized and everything happens in real time.
Today everything moves quickly and technology has added to life's complexity with the magic of fax machines, computers, PDAs, and mobile phones — all capable of delivering multimedia through multiple channels to a mass of recipients, without having to synchronize with anyone. The message is received and the response happens when it happens. The world has changed dramatically since the invention of the analog television over a century ago, yet it's only been recently that television has caught up with our faster mail, faster computers, faster networks, and faster foods. This information overload has forced an asynchronous world where there's too much information and not enough time and resources to absorb it.
When I speak about my work with IBM and the City of Chicago homeland security, I typically get the "Big Brother is watching" comment, referring to George Orwell's omnipresent socialistic watcher called Big Brother in his book 1984. The "Orwellian" fear is that someone, somewhere may be watching you through a video surveillance camera this very minute, and that someone, somewhere is abusing the system to violate your freedom and privacy. Fortunately, you're not doing anything illegal — just reading this book, and hopefully not behind the wheel of a getaway car, idling in front of a neighborhood bank or terrorist target, or speeding through a red light at a high-risk intersection. Yet, if you're not doing anything wrong, you shouldn't worry and there's actually more of a threat from spyware or a Trojan virus on your home or business computer, watching your every move on your desktop, reading your files, and looking through digital photos and movies of your family, than the chance of a video surveillance camera watching your every physical move. While video surveillance monitors the linear world in real time, spyware is software that lives in virtual nanoseconds with computer farms multitasking trillions of computations against millions of unsuspecting data targets in the blink of an eye, making digital data and transactions far more vulnerable and a truly unnerving threat. (Tip: Turn off the computer when you're not using it.)
The security systems I've designed and implemented are strictly for monitoring activity of a potential target, whether from a terrorist threat or neighborhood thieves or vandals. The systems are deployed for the protection of lives and property, not to watch individuals as they jaywalk across the street. Albert Alschuler, a law professor at Northwestern University, makes the point that public camera systems don't violate any privacy concerns because they're installed in public locations. They have been implemented for public safety and crime prevention and aren't for the exploitation of individuals. An individual with a camcorder or the paparazzi may have a more self-satisfying agenda, and thanks to the Internet can violate privacy laws with far more devastating consequences than video surveillance cameras, which are kept secured and in strict confidence.
Digital video security (DVS) works because humans can't be everywhere, all the time. In today's world very few businesses can afford to have human resources sitting behind a desk 24/7, watching television monitors. Such an active approach would also be very limited when dealing with a large crowd. There are too many cameras and too few eyes watching them, but once you plug your video and security systems into the ever-growing telecommunication infrastructure, DVS becomes a very cost-effective and simple replacement for CCTV. It's this complete convergence between entertainment and telecommunications that makes DVS possible. It provides a meaningful solution to video surveillance because you don't have to be actively monitoring an area of coverage to achieve your goals. DVS archives footage using automated software and when a programmed event occurs (e.g., motion, door sensor, vandalism), the DVS system sends an alarm using the asynchronous ways that are already part of today's business infrastructure.
Convergence
DVS is made possible by the proliferation of standardized broadband telecommunication technologies and video compression formats. Once the data pipe reached a level to actively handle heavier loads of data, coupled with the introduction of better video compression quality, algorithms, and processing power, it was possible to deliver hefty video streams from place to place without standardized television signals, DVD players, or game consoles. DVS works much the same way as YouTube, making it possible for anyone, anywhere to receive and view a single stream of video without any compatibility concerns. Only DVS isn't about entertaining or training, but the protection of life and property.
Universal access is made possible by the ubiquitous nature of digital data telecommunications, which can provide cable television, broadband Internet connection, and telephone on a single pipe, while a decade ago it was only a pipe dream (no pun intended). This technological interconnectivity is brought to you by "convergence." Once elusive and now a reality, convergence is the integration of the separate technologies that run our daily lives. This new universal delivery method makes it possible to watch movies or listen to music on the television, DVD player, game console, computer, and mobile phone (Figure 1-2).
(Continues...)
Excerpted from Digital Video Surveillance and Security by Anthony C. Caputo Copyright © 2010 by Anthony C. Caputo. Excerpted by permission of Butterworth-Heinemann. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.
