Posts Tagged ‘ Video Surveillance’



Wireless Night Vision Outdoor Security Cameras

Written By:
Wednesday, May 12th, 2010

Wireless night vision outdoor security cameras are an excellent choice in providing security and surveillance monitoring for both businesses and residential areas alike. Recent advanced technologies in security camera manufacturing have yielded a high quality product with many interesting features at an affordable cost. Let’s take a look at some of the features available for wireless night vision outdoor security cameras and how they function.

Before we talk about wireless night vision outdoor security cameras we need to clarify or make the distinction between what is meant by a “night vision” camera and a day/night camera. Inside the camera is an electronic sensor called a Charged Coupled Device or CCD. Occasionally another electronic device called a Complimentary Metal-Oxide-Semiconductor or CMOS is used instead of a CCD. Both the CCD’s and the CMOS’s purpose is to convert light into electrons that can be monitored or manipulated to create digital images. Each device has its own set of benefits and detriments, but most security cameras employ the use of a CCD, especially when images are required when there is little or no available visible light.

This is true because CCDs can be manufactured that are very sensitive to light; so sensitive in fact that they can produce images from as little light intensity as that available on a moonless night in clear air, which is approximately 0.002 LUX. LUX is a unit that is used to indicate light intensity. A full moon on a clear night in geographical areas outside of the tropics produces light intensity of approximately 0.27 LUX. By contrast, full daylight that is not direct sun light produces 10,000 to 25,000 LUX. Cameras made with these sensitive CCDs are normally called day/night cameras, not night vision cameras. These cameras are designed to produce images in conditions with very little light (very low LUX), but cannot produce images in total darkness. Security cameras that can produce images in total darkness are called night vision or infrared security cameras.

Interestingly, the CCD sensor chip that is used to capture images from visible light is also inherently able to capture images made from infrared (IR) light. Infrared (IR) light is often thought of as the images produced by thermal radiation of objects, however, security cameras utilize what is called the near infrared spectrum. This light is in the 0.7 to 1.0 micrometer wavelength range and is invisible to the human eye. However, wireless night vision outdoor security cameras can “see” this light just like visible daylight and are therefore able to produce high quality images from it. The only difference is that the images produced are monochromatic or “black and white.”

How do wireless night vision outdoor security cameras illuminate their target area? Night vision security cameras normally have a series of infrared light emitting diodes or IR LEDs that are placed around the outside of the camera lens. These LEDs produce light, but only IR light in the near infrared spectrum; the exact light that the CCDs are inherently sensitive to. Therefore, to wireless night vision outdoor security cameras these LEDs in essence produce a spotlight that shines on the target area and illuminates it for the camera while at the same time the human eye is unable to detect the presence of any illumination. Generally, the more LEDs that surround the camera lens, the further the range of the IR camera, to a point. Premium night vision cameras can have effective ranges of up to 300 feet. It’s important to know what distances you will want to cover with your wireless night vision outdoor security cameras so that you can purchase a camera with an effective range.

Wireless night vision outdoor security cameras still require some wiring. When referring to a “wireless” camera, it usually means the camera transmit its images to a receiver using radio waves. This eliminates the need for coaxial cable to be run from each camera to the processor. However, the cameras still require wiring that provides them with the necessary power to operate.

Wireless night vision outdoor security cameras come with a variety of features and accessories. Cameras can pan, tilt, and zoom; they can record not only video but also audio; and they come in a variety of sizes, shapes, and types as well. In addition the system can be networked and viewed anywhere there is internet access.

Few security systems can offer the peace of mind as the constant monitoring provided by wireless night vision outdoor security cameras.

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Wireless Home Security Outdoor Camera Kits

Written By:
Monday, May 10th, 2010

Wireless home security outdoor camera kits can provide you with the peace and comfort of security while providing the ease of do-it-your-self installation. Not only are wireless home security outdoor camera kits easy to install, but they are affordably priced and easy to use as well.

Typical wireless home security outdoor camera kits contain all the components you need to set up your own residential security/surveillance system. They include the wireless security camera(s) and power supply, receiver, processor, and digital video receiver or DVR and/or software and hardware that can enable you to use your personal computer instead of the DVR.

Security cameras require a power source and a method of transmitting their images. This is normally done by wiring the camera with a power source which is provided in the kit, or by a rechargeable battery. The method of transmitting the images is by cabling coaxial cable from each camera to the processor or DVR. Wireless home security outdoor camera kits contain wireless cameras; that is, the cameras do not require the coaxial transmission cable. Instead, wireless cameras transmit their signals through an antenna to a receiver. This eliminates the need to run a coaxial cable from each camera to the processor, personal computer or DVR unit.

Most wireless home security outdoor camera kits utilize the 2.8 or 5.8 GHz radio band to transmit their images to a receiver. Wireless security cameras can transmit on several different channels and one receiver can receive up to 4 different channels. Their maximum range is approximately 700 feet line-of-sight. Line of sight means the ideal transmission route where nothing blocks the sight between the transmitting camera and the receiver. When objects are between the two, wireless security cameras still have a range of approximately 300 feet, depending on the environment.

In addition, these wireless cameras are rated for outdoor use. They may have an IP rating, which stands for ingress Protection. This is an International Electrical standard code that describes the amount of protection the camera unit has to external elements. Most wireless outdoor cameras will have an IP rating of IP66 or IP67 which means they are completely sealed and protected from the harmful effects of dry matter as small as dust and water sprayed as strong jets or when being submerged up to one meter in depth.

Wireless camera systems must have a corresponding wireless receiver to which the wireless cameras’ data is sent. The receiver is much like the base unit of a residential wireless telephone. However after it received the signal from the wireless cameras, it passes the digital information along to a processor, capture board, or your personal computer.

Here the signals are usually reduced in size using CODEC (COmpression DECompression) software or hardware. This process reduces the size of the digital file so that it can be easily handled by the processor and stored on some type of digital media. Digital video files can be extremely large such that without this process even the largest capacity storage drives can be filled to maximum very quickly.

Next the processed digital file is stored on a digital video recorder or DVR. A DVR is a magnetic storage disk just like the hard disk drive in a personal computer. In fact, with the proper software installed, a personal computer can be used to process and store the digital file instead. At some point, the DVR or computer hard drive will reach its maximum storage capacity. When this happens, the DVR or computer hard drive is instructed to begin re-recording over the data it originally saved first. If segments of this data require archiving or copying to provide to police departments for example, recorded material can usually be copied on a USB flash drive or an internal or external DVD writer.

Wireless home security outdoor camera kits have many applications about the home. They can be used to provide general security about the perimeter of the property, both day and night. They are useful for providing security and monitoring of driveways, garage or barn areas, and large, open yards. Tests have shown that just the known presence of a security camera can deter or diminish vandalism and theft.

So don’t hesitate to discuss with our digital security experts about the different types of wireless home security outdoor camera kits and determine which would best suit your needs.

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Home Camera System DVR

Written By:
Friday, May 7th, 2010

A home camera system DVR or home camera digital video recorder could be exactly what you need to acquire the peace and comfort of twenty-four hour seven days a week security and surveillance. Technological improvements have reduced the price of Closed Circuit Television or CCTV monitoring so that not only can businesses enjoy their benefits but the average homeowner can as well. Not only is a home camera system DVR affordable, but it can also be accessed whether you are at home or on the road.

What exactly is a home camera system DVR? It is a group of individual component devices that work in tandem to provide constant monitoring of your home both inside and outside if desired, and at the same time record this monitoring for future use. A typical home camera system DVR consists of 1 to several cameras, a processor or CODEC/capture board, and a digital video recorder. There are many variations and additions available for this basic description. Let’s take a look at each device within the system and see how it can work for your home.

The first device to consider for a home camera system DVR is a security camera. There are various types of cameras with many additional functions than simply recording video. However, the basic camera is a digital, color camera that can capture still digital pictures or motion video. Security cameras have different resolutions, focal lengths, fields of view and other characteristics. To determine what functions need to be included on your cameras, talk with one of our digital security experts.

Most of today’s digital security/surveillance cameras are so sensitive that they can capture images not only in broad daylight, but in situations where there is very little available light. These cameras are called day/night cameras and they contain a very sensitive electronic chip that allows them to function in conditions with low light. On the other hand, if you need a security/surveillance camera that can “see” in total darkness, those are available too.

Infrared or IR cameras can produce black and white images in total darkness. They do this by projecting an infrared light from around the camera lens at the target area. This light is invisible to the human eye but is the equivalent of a spotlight to the IR sensor in the camera. These cameras are excellent for use in monitoring nursery rooms and other indoor rooms at night, dark driveways, garages, and other areas that have no existing light.

There are also security/surveillance cameras that have a pan, tilt, and/or zoom function. These cameras have the ability to move sideways, up and down, and telescopically zoom in on activity, all automatically if needed. These are excellent for monitoring large areas such as large yards, farm land, and other large places.

Digital video is basically many digital photographs taken within just one second. This creates the illusion of motion and this is how motion pictures are created. If you consider the size of a file for just one digital color photograph, it can be fairly large, so taking several digital photographs a second can add up to a really large file size in no time. This is where the processor, capture board, or CODECs (CODEC is an acronym for COmpression DECompression) are needed. They process the digital data sent from the camera, then compress the digital file’s size so the digital file is much smaller without sacrificing the quality of the video. CODEC is an acronym for COmpression DECompression.

Finally, the processor sends the final digital file to the DVR. A home camera system DVR or digital video recorder is actually the same thing as the hard drive on a personal computer. It stores the digital file continuously until the hard drive is full and then re-records new video from the beginning. If necessary, data can usually be copied to another device if needed for distribution.

A home camera system DVR also has the versatility of being viewed from almost anywhere in the world. Today’s systems can be networked over the internet making accessibility possible anywhere that internet accessibility is possible. This is particularly useful if you travel a lot or are away from home for an extended period of time. This can also provide you with 24/7 monitoring by a security/surveillance and alarm monitoring service.

As you can see, there is a home camera system DVR for just about any application. Talk with one of our digital security experts today to get your custom designed system.

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License Plate Capture Basics

Written By:
Friday, August 7th, 2009

As a security dealer, one of the most common requests you will receive from your customer is license plate capture. License plate capture is often confused with license plate recognition so I will first define the difference between the two.

License Plate capture refers to the ability of the security camera to capture an image of a license plate as it passes through its field of view and to record that as an image on a DVR (digital video recorder) so that it can be retrieved at a later time.

License Plate recognition refers to the ability of either the security camera or the recording device to interpret the license plate image as data that can then be compared against other databases.

In most cases license plate capture will satisfy your customer’s needs. There are some great applications for license plate recognition, but we will save that for another article. There are several factors you must seriously consider when attempting license plate capture. They are :

-    Is the traffic controlled?

-    Does the traffic come to a stop at a certain point?

-    How close to the license plate can the camera be mounted?

-    What is the lighting condition?

Ideally, you will mount the camera within a few feet of where the car will come to a stop or slow down. Also, you will attempt to come in from as little of an angle as possible. Each camera should only be responsible for a single lane of traffic (8-10ft). So 2 lanes of traffic, 2 cameras should be used. Now, keep in mind that Megapixel IP cameras are a different breed of camera and we are discussing the use of analog CCTV cameras. Each camera should use a lens that will allow it to zoom in tight enough to where the plate is at least occupying 25% of the captured video image. You do not want to see anything other than the plate with this camera. You can use a different camera as an overview camera to allow you to see everything going on in the traffic lanes.

If you are fortunate enough to have decent lighting, then you may be able to get away with a standard low LUX day/night camera (usually a box camera mounted in an outdoor housing). If there is no light at all, then you will need to use an infrared camera or combine the box camera with an infrared illuminator. When using an infrared camera, you need to watch for IR bounce back, so don’t get a camera that is too powerful. In certain circumstances, you will need to use a WDR (Wide Dynamic Range) security camera in order to filter out certain light spectrums that are causing you problems. For example, you may have an issue with incoming headlights in California when trying to capture plates from the front of a car, or perhaps break lights in the rear are causing the iris to close.

I recommend starting with the least expensive solution and testing out a single camera to see if it will work for you. If you have issues, then progress to the next level. Once you have the camera installed, you will need to configure the DVR. I recommend setting the DVR to the highest resolution available, even if it means sacrificing frame rate. Recording at D1 will give you an image 4 times as large (4 times as much detail) as an image recorded in CIF resolution. Be sure to check both daytime and nighttime recordings.

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CCTV Lens Technology

Written By:
Friday, August 7th, 2009

One of the main considerations when installing a security surveillance system is the lens.  Without lenses, the system would be useless.  Most cameras come with a choice of lenses, while box type security cameras require you to choose the lens and purchase it separately.

When choosing a lens, there are a few things to keep in mind.  First, how far do you want to see, and what level of detail do you want to see.  Lenses with a fixed focal length are simply known as fixed lenses.  Fixed lenses are available in a variety of focal lengths, however, the most common fixed lens is a 3.6mm lens.  This lens will give you approximately 75 degree field of view and will allow you to see a fair amount of facial detail up to about 30 feet.  This would be a great choice for an overview camera.

If an overview camera is not sufficient to capture the desired field of view or distance, then lenses with various focal lengths can be used to achieve the desired result.  The human eye equivalent of a CCTV Lens is a 3mm lens.  So, anything smaller than that would be considered a wide angle lens and anything larger would be considered to have some level of magnification.  For example, a 2mm lens would allow you to capture a much wider angle of view than the human eye, but the distance that you could see in any detail would be small.  In comparison a 100mm lens would allow you to see a high level of detail at a great distance, but the angle of view would be very narrow.

Let’s suppose that you aren’t sure what distances or angle of views will meet your needs, or that the distances and angles may change from time to time.  Then, in that case, a lens with a variable focal length would be needed.  These types of lenses are known as varifocal lenses.  These lenses are basically manually operated zoom lenses.  Varifocal lenses are also available in a variety of focal length ranges.  One of the most common sizes of varifocal lens is a 2.8-12mm focal length.  This lens can be adjusted from 2.8mm (wide angle) to 12mm (zoom) to accommodate a range of camera requirements.

Although varifocal lenses would be considered zoom lenses, in the security industry a zoom lens is a lens that can be mechanically or electrically zoomed.  These types of lenses can be remotely zoomed in or out from the DVR or other remote method.  This would allow the camera to act as an overview camera most of the time and then be zoomed to capture a small detail when needed.    The most common zoom lens you will find is a part of a Pan/Tilt/Zoom or PTZ type of camera.  These lenses have a motorized zoom, while the camera itself has a motor allows the camera to move up or down and rotate.

The camera lens is like the human eye; without them we couldn’t see.  Without lenses, your security surveillance system would not be able to capture images.  And, just as we use telescopes and magnifying glasses to enhance our vision, you can enhance the functionality of your surveillance system to maximize its capabilities.

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