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Transcript of Cctv camera
- 1. Technology Showcase
By Jay Ankeney
2. In a world of heightened security concerns in the post-9/11 era, attitudes toward security surveillance are changing. Increasingly, the idea of visually monitoring airport crowds, or knowing a closed-circuit TV (CCTV) camera is observing the area when we visit a darkened ATM or park in an unlit car lot, can bring an added sense of comfort to the unprotected. In response to our communal angst, and the very real economic impact of theft ranging from petty to grand, the security camera industry has been busy developing new technologies for the Department of Homeland Security, the military, law enforcement, schools, and various retailers.
The purpose of CCTV is to transmit a controlled observation signal to a limited set of monitors. Who watches those monitors is a question of security versus privacy, but the technology enabling it dates back World War II when the Germans set up an extensive CCTV system to view the launching of V2 rockets at their Peenemnde test site. In the 1960s, the British developed extensive public CCTV systems in response to IRA bombings in the United Kingdom, and their 1994 Home Office report titled CCTV: Looking Out For You, paved the way for a massive increase in the installations of CCTV systems.
3. Many modern American tourists are astonished at the number of closed-circuit cameras easily visible on the streets of most European cities. A 2002 working paper by Michael McCahill and Clive Norris of UrbanEye estimated that there are 400,000 surveillance cameras in private premises in London alone. In fact, the identities and movements of several of the subway bombers that hit London on July 7, 2005, were captured using CCTV cameras.
4. THE BASICS
Regardless of national security and civil liberty considerations, the goal of companies making CCTV systems is simply to bring the pictures back to those monitoring them with clarity and reliability. Originally, the cameras were naked box-type installations that were vulnerable to both vandalism and the elements. But starting in the early '90s, installers began housing them in semi-transparent domes, the kind that have become ubiquitous features in the ceiling of every Las Vegas casino. Domes not only make the camera more stealthy, but they are also easier to install because they require only a single mounting bracket.
The International Electrotechnical Commission (IEC) has produced a set of standards referenced under IEC 60529 called IP or International Protection codes (not to be confused with the more common Internet Protocol acronym). The goal of the IEC's IP codes is to classify the degree of protection provided by these enclosures by rating these domes' ability to withstand environmental damage and what the IEC calls ingress of solid foreign objects.
5. the X's represent numerals from the coding scheme. The first X in the sequence signifies the degree of protection against solid objects ranging from 0 to 6. The second X represents the degree of protection against moisture and can range from 0 through 8. For example, IP23 means the enclosure can withstand solid foreign objects .5in. in diameter and larger and is protected from moisture as aggressive as spraying water. IP65 indicates the dome is dust-tight and protected from moisture challenges up to jetting water.
6. Beyond this, many CCTV manufacturers have made their domes ruggedized or vandal resistant, and although their claims for protection do not have universal standards yet, dome camera representatives talk about them being able to withstand the swing of a baseball bat or even a 10lb. sledgehammer. Clearly, a security camera is not really secure unless the camera itself is protected.
7. Inside those domes there are two general types of CCTV cameras: fixed and PTZ (pan, tilt, zoom). As the name implies, PTZ cameras can be directed to oversee desired surveillance areas either by personal manipulation or by preset computerized control. To interpret the images these cameras capture, there has been rapid development in both motion detection software and what is increasingly being called imaging analytics, which can analyze movement on the screen based on pre-determined parameters.
Sony has come up with its own advance on analytics called Distributed and Enhanced Processing Architecture (DEPA), which divides the processing tasks by placing analytic capabilities in digital cameras matched with back-end processing capabilities at the networked recorder. The intent of DEPA is to minimize operator error by distributing processing power throughout the entire system. As an open development platform, DEPA-enabled products are available from several other recording system developers.
8. Because security violations often happen at night, many cameras incorporate dual-resolution image-capture systems that record full-color pictures in daylight, then switch to lower-resolution but higher-sensitivity black-and-white surveillance in the dark. Some even include their own invisible infrared illumination systems, which let them capture IR images when perpetrators think they are operating in total darkness. Even more elaborate image reception is made possible by the Digital Pixel System (DPS) developed by Pixim Technology and built upon technology developed at Stanford University in the 1990s. Pixim's DPS non-destructively samples each individual pixel multiple times in a single capture frame. Several surveillance camera manufacturers use DPS to extend the dynamic range of their recordings.
9. By industry convention, security cameras are divided into either analog or digital, depending on what kind of signal they transmit. Cameras outputting an analog signal are useful when the system has to interface with legacy routers, switchers, and CRT displays from the days before bits and bytes. Digital cameras have either onboard servers with their own IP address or dedicated ancillary digital processing capabilities to turn their images into computer-friendly data that can be transmitted via Ethernet and displayed on an authorized laptop. These IP-enabled cameras can be monitored from anywhere in the world via a web connection with software encryption.
GE Legend IP
10. A recent development in IP empowerment is Power over Ethernet or PoE technology, standardized in 2003 as IEEE802.3af, which lets the Ethernet connection provide enough electrical power to run the camera over the same Cat-5 cable that transmits the data. A company called PowerDsine has been a leader in developing PoE technology, having pioneered it in 1998. PowerDsine's technology is marketed in private-labeled midspans (PoE injectors) offered by more than 16 vendors, in addition to its own midspan (PoE injector) products sold under the PowerDsine brand in Europe and North America. As well as working with more than 70 vendors, PowerDsine has independently tested and certified more than 100 PoE-compliant network devices to ensure conformance with the IEEE 802.3af standard. On Oct. 24, 2006, Microsemi, a designer and manufacturer of high-performance integrated circuits and semiconductors, announced that it had entered into a definitive agreement to acquire PowerDsine and its PoE technology.
11. MAJOR SYSTEMS
Frost & Sullivan, a market research firm covering the video surveillance market, estimates a growth rate of 8.4 percent in domestic security camera sales in 2006, topping $1.7 billion in North America alone, while estimating $3.2 billion worldwide. With the rise of U.S. government and private investment in domestic security systems, products from Asian producers have burgeoned beyond counting. Following is a sample of the most interesting dome camera systems from leading manufacturers who have a major presence in the United States. Recognizing that each company offers an extensive variety of surveillance systems, a representative of each brand was asked what was the latest and most exciting in their CCTV dome camera line.
12. Providing simultaneous Motion JPEG and MPEG-4 compression, the Axis 232D+ network dome camera from Axis Communications has a built-in web server and features an 18X optical zoom and auto focus lens. The Axis 232D+ has a removable IR-cut filter for superior day/night surveillance capability, which can be boosted with an ancillary solid-state LED IR illuminator. The Axis 213 PTZ network camera has a built-in IR illuminator and provides wide coverage with its ability to pan 340 degrees. In addition, the 0 212 PTZ uses an ultra-wide-angle lens with a three-megapixel sensor to cover a 140-degree area without any moving parts. The PTZ function is controlled by the observer's selection of viewing area.
13. The weather-resistant EnviroDome camera systems from Bosch are IP66-rated and operate with privacy masking and sector blanking. EnviroDome cameras are remotely configurable (Bilinx, Biphase, RS-232, RS-485), and can be fitted with an AutoTrack motion tracking option for hands-free operation, even while the camera is moving. The Bosch AutoDome indoor systems come in day/night or color and B/W versions with 26X (day/night) capabilities or 18X optical zoom range plus a 12X digital zoom. Both of these analog cameras from Bosch can be fitted with A/D converters for digital IP operation while simultaneously providing an analog signal.
The Altitude 9440 is the most recent addition to DVTel's line of MPEG-4-based IP cameras using the Pixim DPS with 1/3in. format CMOS imager. MPEG-4 lets the Altitude 9440 provide both high-frame-rate and high-resolution video while maintaining significantly lower file sizes that require less bandwidth. The Altitude 9440 Mini-Dome camera uses IGMP Snooping (Layer-2 multicasting) technology, which enables a single stream to be transmitted to multi