A guide to Digital CCTV and choosing Digital CCTV Products

Security has never been more important, with sophisticated systems increasingly relied upon to serve and protect both people and property.

Millions of dollars are lost each year by retail organizations due to shoplifting, point of sale fraud and employee theft. To protect themselves, retailers have recognized the importance of implementing CCTV surveillance equipment. The video surveillance solution, with its point of sale add-on POS, is helping retailers combat the losses by providing advanced recording and retail surveillance management which can be managed across the LAN and Internet.

Retailers of all sizes are recognize the value that browser-based digital video management software brings to reducing customer and employee theft the software also improves employee and customer safety, improves risk management, and increases operational efficiency each year the retail community loses millions of dollars the research indicates that employee theft, customer shoplifting, and point-of-sale fraud will not only continue, but it is expect to increase exponential.

Protection of people, property and a way of life are the essence of Homeland Security and other global anti-terrorism initiatives. On a national scale, these are massive mandates. Internet based video surveillance provides a vital component in an integrated network of security equipment and personnel.

Our scalable browser based software provide comprehensive video surveillance, monitoring and security video management for public and private locations.

Public safety and first responders including law enforcement, fire, medical and other emergency service organizations can all rely on both mobile and fixed video surveillance systems.

Digital CCTV, is the technology used in modern surveillance systems. Traditional ,VCR, CCTV pictures are sent via cctv cameras to a closed area, e.g. a CCTV Monitor, this type of CCTV is likely to produce lower resolution images and have to be displayed via cabling in the workplace. Modern Digital CCTV Systems can be operated remotely via a pc or mobile phone, can monitor various locations and can be monitored from wherever there is internet or GPRS Access.

Analogue CCTV

In the past, all CCTV Cameras were attached to a Multiplexor (A device that will split multiple camera pictures onto an individual CCTV Monitor). The Multiplexor then sends the analogue camera images to a Time Lapse Video Player. These are special CCTV recording devices that can record up to 960 hours of footage on a three hour Video Cassette. This method is still used today for simple CCTV installations but the quality of recording is usually very low (1 Frame Per 12.8 Seconds). Many systems still use Analog cameras and will be come obsolete to the Digital world.

Digital CCTV

Currently the majority of CCTV systems use Digital technology. Digital CCTV Surveillance uses current PC technology to digitize the CCTV camera images and compress them into a PC friendly format. These digital images can then be stored on a PC’s Hard Disk Drive. As the digital cctv images are stored on a computers Hard Drive it is possible save digital cctv footage and access it speedily and easily. Digital CCTV also has the advantage over Analogue CCTV systems that the image are of a far higher resolution.

The Different Camera Technologies

Camera Technologies

Indoor Cameras:
Indoor cameras come in all types, sizes and styles. The most popular is the smoked mini dome camera. The dome camera can be mounted on the ceiling or wall and adjusted to view any angle. Although the dome is designed to protect the camera inside, they are not weather tight and should not be installed where they are exposed to moisture or extreme temperatures.

Indoor Dome	Box Camera	Vandal Proof	Night Vision	Bullet

Outdoor Cameras:
The only difference between indoor and outdoor cameras is that the outdoor cameras are in an environmentally protected housing. Some housings have heaters and blowers to keep the temperature inside within the operating parameters of the camera. Others such as the mini outdoor bullet cameras generate their own heat for operation. All outdoor cameras discussed in this guide are designed to operate in -10 degrees to 120 degree temperature.

Day/Night or Night Vision:
Affordable night vision cameras are the latest innovation to the video surveillance industry. There are many types and styles to choose from but they all have one thing in common, infrared LED’s. Small LED’s that transmit out infrared light surround the cameras lens. The LED’s cast out light the camera can see but the human eye cannot. The distance a camera can see in the dark is based on how many LED’s the camera has. As a rule a camera with 10-20 LED’s can see 20 feet in complete darkness. Some cameras such as the one below can see up to 70′ in complete darkness. Notice the LED’s surrounding the camera lens.

  

These cameras provide high quality color pictures during the day and when the light levels drop past a minimum level, they automatically switch to night vision or black and white pictures in complete darkness. When the light levels increase the camera automatically changes back to color video. These cameras are very reliable and flexible and should be considered when designing your system.

Low Light Cameras:
Low light cameras are color cameras which need very little light to operate (.1 lux). They work well in most applications but they do require some lighting, similar to the lighting provided in a romantic restaurant.

Hidden Cameras:
Because cameras are so small now they can be hidden in almost anything. It’s common to see cameras in pictures, clocks, radios, smoke detectors, motion detectors, books, ties and anything else we can dream up. The cameras are the same cameras used with standard indoor cameras. The only difference is the housings used.

      

Pan Tilt Zoom Cameras:
PTZ cameras, as they are called, are considered “top of the line” in security cameras. They can pan 360 degrees, tilt 270 degrees, and optically zoom in as much as 22 times. They are controlled and programmed with either a desk top joy stick control or through the software of a PC based DVR. They come in both indoor and outdoor versions, can be wall or ceiling mounted, and can be equipped with color Day/Night cameras or night vision.

 

 

 

 

 

The cameras can be programmed to automatically run preprogrammed tours, automatically panning, tilting and zooming to predetermined locations. They can also be programmed to pan, tilt and zoom to a specific view if motion is detected or a pre-defined alarm occurs. A user can override the automatic operation and control the cameras as needed. Up to 16 PTZ cameras can be installed on most DVR systems (as long as the DVR supports 16 cameras). The cameras are controlled with a two wire communication wire which loops from one camera to another. Each camera has dip switches which are used to set its address. The comm. wire can have a maximum distance of 3000 feet. In addition to the communication wire each camera also required a video cable to transmit the video signal back to the front end.

MPEG

Stands for the Moving Picture Experts Group MPEG is an ISO/IEC working group, established in 1988 to develop standards for digital audio and video formats. There are five MPEG standards being used or in development. Each compression standard was designed with a specific application and bit rate in mind, although MPEG compression scales well with increased bit rates. They include:

MPEG-4

Standard for multimedia and Web compression. MPEG-4 is based on object-based compression, similar in nature to the Virtual Reality Modeling Language. Individual objects within a scene are tracked separately and compressed together to create an MPEG4 file. This results in very efficient compression that is very scalable, from low bit rates to very high. It also allows developers to control objects independently in a scene, and therefore introduce interactivity.

JPEG

Stands for Joint Photographic Experts Group. It is also an ISO/IEC working group, but works to build standards for continuous tone image coding. JPEG is a lossy compression technique used for full-color or gray-scale images, by exploiting the fact that the human eye will not notice small color changes.

 

H.264

H.264, also known as MPEG-4 AVC (Advanced Video Coding), is a video compression standard that offers significantly greater compression than its predecessors. The standard offers up to twice the compression of the current MPEG-4 ASP (Advanced Simple Profile), in addition to improvements in perceptual quality. The H.264 standard can provide DVD-quality video at under 1 Mbps, and is optional for full-motion video over wireless, satellite, and ADSL Internet connections.

Terms

Codec – A video codec is software that can compress a video source (encoding) as well as play compressed video (decompress).

CIF – Common Intermediate Format – a set of standard video formats used in videoconferencing, defined by their resolution. The original CIF is also known as Full CIF (FCIF).

QCIF – Quarter CIF (resolution 176×144)
SQCIF – Sub quarter CIF (resolution 128×96)
4CIF – 4 x CIF (resolution 704×576)
16CIF – 16 x CIF (resolution 1408×1152)

Camera Specification Guide

Camera Specification Guide

Below you will find operating details on the various aspects of security cameras. If it seems confusing simply refer to the camera flow charts listed below. All the cameras listed meet and exceed the minimum standards for professional surveillance applications. A lot of this information is good to review but you really do not need to memorize it.
Lines of Resolution:
Each cameras performance is based on the number of horizontal lines the chip in the camera provides. The lines of resolution dictate the quality of the video the camera can produce. The higher the lines of resolution, the better the quality.

Performance	Color	Black and White
Standard	330 Lines	380 Lines
Medium	420 Lines	470 Lines
High	480 Lines	580 Lines

Lens:
The lens dictates the field of view the camera provides. Lenses range from 2.8mm to 18mm on an average. The larger the lens size the farther it will view. The draw back to a 12mm or 18mm lens is that the horizontal view narrows to as little as 15′.

Distance Charts

**As a general rule we recommend standardizing your cameras 3.6mm lens. They are designed to be installed in a corner, provide a 90 degree field of view, and provide effective surveillance in a 30′ x 30′ area. The number one mistake when designing a camera system is that we all expect one camera to do the work of two or three. Bottom line is, unless you pay the big bucks for a Pan, Tilt, Zoom camera, don’t expect a camera to effectively cover more than a 30-50 foot area.

Auto Iris:
Almost all cameras have either a digital or mechanical auto iris. Most cameras have them built in. Do not consider a camera without auto iris. You will constantly be adjusting the camera as the light levels change.

LUX or Minimum Light:
When choosing your cameras pay attention to the amount of light which will be available in the areas you want to see. Most color cameras have a .1 lux minimum which means not a lot, but some light is needed for operation. You can tell if a color camera does not have enough light to operate because the picture will go grainy. If you are not sure you have enough light consider using night vision or black and white cameras. Black and white cameras have a .01 lux minimum and do much better in low light. Night vision cameras can see in complete darkness or 0.0 lux. See the camera section for more detail.

Power:
Cameras are powered with either 12V DC or 24V AC power. It does not matter which you choose as long as you don’t connect a 12V camera into a 24V power supply or 24V camera into a 12V power supply. We recommend using 12V DC cameras and power supplies. See our Power Supply section for more detail.

Viewing Angles

Viewing Angles

Below are samples of the “fields of view” which the most common lenses provide.

3.6 mm / 6 mm / 8 mm / 3.6-8 mm / 25 mm / 6-15 mm / 6-96 mm