Posts Tagged ‘ monitoring ’

Video Surveillance Cameras

Monday, March 21st, 2011

Today’s video surveillance cameras have made “leaps and bounds” in technological improvements compared to the cameras from just 10 to 15 years ago.  Not only that, but the camera’s prices have steadily decreased with the increase in technology.  All of this has lead to video surveillance cameras becoming a “household word” for family protection and safety as well as business protection and workplace documentation.

Original video surveillance cameras were based on analog signals.  These systems and components of the systems were often referred to as CCTV or Closed Circuit TeleVision.  CCTV was so named because although it closely resembled a typical television studio system, there was one major important difference.

Studio television cameras’ video signals were boosted by the broadcast station and sent via radio frequency via a large antenna.  Once the signal left the broadcast antenna, anyone with a receiver could pick up the signal.  Video surveillance cameras however, sent their signal along a cable, directly to a specific monitor and recording device.  In this respect, the system was a “Closed Circuit Television” system.  In fact, any system used for monitoring, surveillance, or security in this manner was referred to as a CCTV system.

Today, video surveillance cameras still operate on a CCTV based system, but to be accurate, we must redefine CCTV to make it somewhat looser in application.  Although modern digital video surveillance cameras also transmit their video signals via a cable to a Digital Video Recorder or DVR and one or more monitors, they also employ additional methods for transmitting their signals that must be taken into consideration of the definition of CCTV as well.

These cameras may also transmit their video data wirelessly via an on-board camera transmitter and antenna.  These cameras use modern day wireless technology often used in land-line based telephones such as 2.4 or 5.8 GHz technology or 900Mhz technology for broadcasting their signal.  These systems are designed to transmit their signals only a fraction of the distance of the older systems, as they are aimed at sending their signals to a nearby receiver, which is usually plugged in by cable, to a DVR and/’or monitor.

Another method that is employed today is the use of the Internet as a vehicle for networking and transmitting.  Both video surveillance cameras and DVRs have the capability for connecting to the Internet.  When they do possess this feature they are often referred to as Internet Protocol or IP ready, because they deliver their transmission using IP format technology.

Although it is true that individuals other than who the video images are intended for can gain access surreptitiously, the intent of these wireless broadcasts and Internet transmissions are directed to a limited number of very specific viewers.  Thus, although our definition for CCTV as now become a bit broader in scope, it is easy to see why even today, video surveillance cameras are often called CCTV cameras.

While we are on the subject of CCTV versus new video surveillance cameras, it would be prudent to mention that there is some carry over from the “analog days” of CCTV to the current “digital era” which can make the comparison of components or the selection of a system somewhat confusing.  This primarily involves the use of reference to the detail or resolution of the video image created by the camera and displayed by the monitor.

Electronic video images may show a varying degree of detail.  That is evidenced by the contrast between standard television broadcasts and those called High Definition (HD).  Television was originally displayed on a Cathode Ray Tube or CRT (also called the “picture tube”).  The CRT reproduced the image on its screen by shooting an electron beam horizontally at the rate of about 60 times per second.  To a large degree, the number of horizontal lines determined how detailed the video appeared.  The more lines, the smaller the lines, the greater the detail of the picture.

Today, however, most televisions are like computer monitors; they are either Liquid Crystal Displays (LCD), plasma, or Light Emitting Diode (LED) displays.  These monitors display tiny dots called pixels instead of horizontal lines, therefore, they can display a much higher detail picture.  Yet, many video surveillance cameras still specify their picture quality in terms of the older, horizontal line method.  Its important to know that the lower end of resolution or detail is from about 300 up to 650 TVL (TeleVision Lines).  Video surveillance cameras with 650 TVL displays can produce very high definition video images.


Backup Monitoring System with Camera

Friday, August 13th, 2010

A backup monitoring system with camera is perfect as a rear vision solution for large recreational vehicles, semi tractor trailers, school buses, giant construction equipment, boats, and any other moving vehicle that has blind spots or difficult to see areas. A backup monitoring system with camera provides a higher level of safety and peace of mind when putting vehicles in reverse.

Although these systems were originally designed for oversized vehicles, they are not limited to oversize vehicle use. A backup monitoring system can be helpful for individuals that find it difficult to use mirrors or have a physical disability that does not give them the freedom of movement to turn around and look behind them when backing up.

Although components can be purchased separately, a back up monitoring system with camera normally contains everything you need in one easy do-it-yourself kit. Compared to typical mobile security and surveillance monitoring systems these systems are relatively simple as they don’t require a Digital Video Recorder or Flash memory on which to save digital video files.

In fact there are just a few components that are needed for a backup monitoring system with camera. They include:
• A digital video camera
• A typical DC 12V power supply
• AN LCD monitor and cables if needed

There are generally three different types of digital video cameras that are used on backup monitoring systems. Bullet cameras are small bullet-shaped cameras that can usually be flush mounted in large bumpers or panels of large vehicles like trucks and SUVs.

Surface mount cameras are mounted to the surface of the vehicle using a metal bracket. These are probably the most popular type of camera used for backup systems, especially for large vehicles such as semi tractor trailers, recreational vehicles, and large construction vehicles.

For cars, the most popular and probably the easiest to install is the license plate camera. These cameras are convenient and easy to install as they normally use the license plate mount for attachment. They come in two different types; bar cameras and frame cameras. Bar cameras attach over the license plate to the top or bottom using existing plate mounting hardware. Frame cameras look like ordinary license plate frames that surround the plate and are also mounted in existing hardware locations. Neither type obscures or covers any part of the license plate data.

Typical cameras require two different wire connections. One wire must be run from the camera to the monitor for the video transmission. The second wire must be run to from the cars 12V DC power supply to the camera. Wireless cameras are available that eliminate the need for a video transmission wire. These cameras only require hook up to the vehicle’s power supply.

The 12V DC power supply needed to run the backup monitoring system with camera is the same power supply needed to operate the vehicle. In other words, the system runs off the car’s power. Normally there are two different locations in the system that will need power; the camera, already mentioned and the monitor. Most external type monitors have cigarette lighter plugs that easily plug in and out when needed.

There are several types of monitors that can be used for a backup monitoring system with camera. The monitors are generally LCD displays. The most commonly used monitor is the 3.5” LCD color monitor. This monitor is a surface mount monitor and can usually be mounted to the dashboard or window location using a supplied suction cup mount. However, there are other monitor types available that include:
• In-dash monitors
• Overhead monitors
• Flip-down monitors
• Sun Visor monitors
• Rear View Mirror Monitors

The entire system is a cinch to install and can easily be done in less than 1 hour. Once the system is installed, it’s just a matter of turning the unit on to use it – a small endeavor for such a huge safety addition. So even though a backup monitoring system with camera may be a necessity on certain large vehicles, they also make great safety insurances and reverse driving aids even on average sized cars.


Home Camera System with DVR

Friday, June 25th, 2010

A home camera system DVR or Digital Video Recorder is a standalone digital video security camera system suitable fur residential use. Recent advances in computer and electronic technology have provided the home camera system DVR user with an abundance of optional features, making the system versatile enough to be used just about anywhere.

A home cameras system DVR is basically a component system. There are different parts that make up the entire system and each individual part can differ to provide a specific function. These “parts” are the components and when put together create the system.

A typical home camera system DVR consists of the following components:
• Camera or cameras;
• Power supply;
• Processor/Digital Video Recorder with CODEC utility; and,
• Monitor

Cameras used in a home camera system DVR may be indoor or outdoor types. Outdoor cameras have a protective cover that keeps dust, water, weather and other environmental elements from penetrating it and harming the camera. These cameras are often rated based on a standard called an Ingress Protection or IP rating. When shopping for an outdoor camera, make sure it has a rating of either IP66 or IP67. Both ratings indicate complete protection from dust and water.

When creating your own custom home camera system DVR, you generally will require both outdoor and indoor cameras. Outdoor cameras may be used for monitoring the perimeter of your residence or for specific outdoor areas. Indoor cameras are generally used for monitoring rooms, doors, and areas inside the home.

Regardless if the camera is an indoor or outdoor model, each camera will need to be connected to a power supply, and a coaxial cable will need to be run from each camera to the processor/DVR. However, the coaxial cable can be eliminated by using wireless cameras instead.

A wireless home camera system DVR differs from a standard home camera system DVR in that each camera has its own transmitter and antenna. The camera transmits its video signal using the 2.4 or 5.8 GHz radio band to a corresponding receiver. The receiver is usually in the same location as the DVR. The receiver passes the radio signal in electronic form to the processor/DVR. Wireless cameras are quick and easy to install.

The digital video cameras used in a home camera system DVR are state-of-the-art electronic devices. They create a digital video image by capturing light from the lens on a special electronic sensor chip. There are two types of sensor chips; Charged Coupled Devices or CCDs and Complimentary Metal Oxide Semiconductors or CMOSs. These chips range in size from less than ¼ inch to about 1 inch. Generally, the larger the chip, the greater the resolution of the video image that is produced.

Cameras may contain special highly sensitive chips to produce digital video under different lighting conditions. Day/night vision cameras produce high quality color video with very little available visible light. Night vision infrared cameras produce high quality color video under normal lighting conditions and high quality monochrome or black and white video under infrared conditions.

Night vision infrared cameras contain Light Emitting Diodes or LEDs that project infrared light onto the target area of the camera. This illuminates the target area like a spot light or flood light; however the human eye cannot see this light. On the other hand, the camera can see the infrared illumination and indeed uses it to produce a clear, high quality video,

Day/night vision cameras require at least some sort of visible light; night vision infrared cameras can produce an image in total darkness. However, infrared cameras are limited to how far they can “see” in total darkness based on the LEDs used to illuminate the target area. If your home camera system DVR requires infrared cameras, be sure to check the range of the camera before purchasing to make sure you have one that will fulfill your needs.

Other available options for cameras include audio recording, and Pan-Tilt-Zoom (PTZ) functions. A PTZ camera with motion detection can be programmed to track moving objects.

The DVR of a home camera system DVR is like the hard disk drive on a personal computer. Its main function is to store the digital video files. Raw digital video files are extremely large which makes them difficult to store and handle. The DVR uses a CODEC utility to shrink file size but retain video clarity. DVRs can be purchased in a variety of storage sizes ranging up to several Tera bytes.