Posts Tagged ‘ video camera’



Security Video Cameras

Written By:
Wednesday, March 23rd, 2011

Security video cameras are one of three major components of today’s digital video security systems which also consist of a Digital Video Recorder or DVR and one or more monitors.  The digital video camera is an interesting piece of electronic wonder, and as technology continues to advance so do the features and abilities of the security video camera.

In this article, we’ll take a look at how a security video camera operates.  We’ll also take a look at some of the more common features and options that are available on today’s digital video security cameras.

Security video cameras are electronic based devices that transfer light images into electrical images that can be viewed on a monitor.   One of the key factors in accomplishing this is the electronic sensor that is used inside the camera to do the conversion.  Cameras make use of one of two different technologies with either one yielding the same end result.

 

These sensors are called a Charged Coupled Device or CCD and a Complementary Metal Oxide Semiconductor or CMOS.  The lenses focus the light image onto this small sensor chip (most range from about 1/4 inch 1/2 inch square).  The chip is sensitive to light energy in such a way that when light strikes the chip and electrical impulse is created that can be measured and used to construct a video image.

Ironically, even in digital security video cameras, the video signal that is created is originally analog in nature.   The signal is passed through a special Integrated Circuit or IC chip known as a analog-to-digital converter as well as a Digital Signal Processor or DSP before it is sent out the camera to the DVR.  In most systems the signal is sent along a cable (RG-59, CAT5, etc) from the camera directly to the DVR or monitor; hence the often used phrase “Closed Circuit TeleVision” or CCTV.

Once the video data reaches the DVR, it must be worked on some more by the DVRs DSP.  The data is gathered or compiled into a file called a digital video file.  Security video cameras create digital video files that can be played back by most personal computers and DVD players.  This digital video file is actually several digital photographs taken in raped succession over a very short time (usually around 30 photographs or frames per second or 30 fps).

The digital video file can quickly become several Gigabytes in size, especially when there are multiple cameras (which is usually the norm) recording at the same time.  There fore to make handling of the file easier for the processor and to get the maximum amount of time-recording per given storage capacity, the file is reduced to a fraction of its original size.

This is done by a COmpression/DECompression or CODEC utility.  The utility may be hardwired (usually an IC chip) or it may exist in the form of software.  Basically, a CODEC is a mathematical algorithm that finds a way to store repetitive data only once, thereby reducing file size while maintaining video quality.  Security Camera King’s DVRs all use the latest, most efficient CODEC known as H.264.

Security video cameras come in a variety of shapes, sizes, features, and price ranges.  Covering all of these variations is by far, beyond the capacity of this article, however we will attempt to try to cover some of the more popular characteristics.  If you would like additional more specific information on a camera variation, try searching our knowledge base for more information.

 

There are basically four types of security video cameras based on shape.  They are:

  • Box cameras;
  • Bullet cameras;
  • Dome cameras; and,
  • A variety of different hidden or disguised cameras that take the shape of the device they are built into.

These cameras are further made in one of three different styles based on where they are intended to be used.  These are:

  • Indoor cameras;
  • Outdoor cameras; and,
  • Indoor/Outdoor cameras.

In addition, cameras can come with a myriad of features.  Depending on the manufacturer and camera model, some features may be considered standard issue for the camera while others will be considered an option, usually with an additional cost:

  • Infrared night vision;
  • Pan-Tilt-Zoom (PTZ);
  • Motion detection;
  • Very high resolution output;
  • Audio capability;
  • Internet compatible;
  • Explosion proof; and,
  • Wireless.

Generally speaking, if you have a specific security video camera need, there’s one out there that can nicely fit the bill.

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Color Security System

Written By:
Friday, February 4th, 2011

Color Security SystemA digital video color security system is a video camera based protection and monitoring component system. Although a bear-bones system may only require two separate devices to operate, it normally consists of three or more. At a minimum a color security system requires at least one camera and a Digital Video Recorder or DVR. However, if you want to be able to watch what your system is recording, you will also want to use the third component, a color monitor.

The “work flow” of a color security system begins with, and is really based on, the digital video color security camera. A color security system may have only one camera, or it can consist of as many as sixteen when the system utilizes one DVR. The camera or cameras send their color video data to the DVR unit which contains an on-board computer processor designed specifically to do work with color video data and coordinate the color security system functions. Once the processor has interpreted the digital data from the camera, it compiles the data into a digital video file which can be viewed live if a monitor accompanies the system and/or saved for later use on the DVR hard disk drive.

The digital video camera in a color security system records digital images by converting light energy into electrical energy. It does this using one of two different sensors that create measurable electronic charges when light strikes their photosites. The sensors are known as Charged Coupled Devices or CCDs or Complimentary Metal Oxide Semiconductors or CMOSs.

These sensors have tremendously small diodes in an incredibly small amount of area. Most color security system cameras’ sensor chips are less than 1/2 inch square in size. The lens focuses the light image on this small area, which on a typical 1/2 inch CCD can contain 300,000 to 500,000 photosites. The sensors’ photosites are usually designated to detect red, green, or blue light. This configuration is often called a Bayer filter. When the data from all of the red, green, and blue sensing diodes or photosites is compiled it creates a high quality electronic color image.

The color security system further processes the electronic image by passing it through an on-board circuit chip called an analog-to-digital converter. This converts the electronic analog signals into binary or digital data that is then transmitted in a variety of ways, one of the most common being along an RG-59 coaxial video transmission cable. (Signals can also be sent wirelessly via radio waves).

The other end of the cable is connected to the DVR unit. The data from the color security system camera is still unrefined and it is the responsibility of the DVR unit with its accompanying Digital Signal Processor or DSP to add the finishing touches. It does this by using a utility, either in software form or contained in an on-board microchip, that reduces the size of the otherwise incredibly large digital video file without sacrificing a significant amount of quality.

Digital video, like cinematography, actually consists of several photographs (digital-based in this case) that are taken in a very short period of time. The human eye and brain are slow enough to fool into thinking they are seeing fluid, motion video if the photographs pass by quick enough. The number of photographs taken in one second is usually called the “frame rate” and is designated as “frames per second” or fps and is typically around 29 fps.

Consider the file size of a typical high quality digital camera. Now multiply that size times 29 and you have the size of the digital file for one second. Multiply that times 60 seconds, and again times 60 minutes, and the result for one hour of video at that rate is 104,400 times the size of one digital photograph. You can appreciate how large the file size can be.

Every color security system uses a form of the utility mentioned above. One of the most recent and efficient COmpression/DECompression or CODEC utilities is the H.264. Using the CODEC makes the files much easier to handle and increases maximum storage capacity of the DVR.

Security Camera King features several different color security systems including our Elite Mini, Elite, and Ultimate DVRs. We’ve designed our color security systems to give you the freedom to change components to make the system fit your specific needs. Contact one of our security experts today for more information.

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Security Cameras for the Home

Written By:
Monday, September 27th, 2010

There are several types of security cameras for in home use. In fact, just about any security camera can be used for residential purposes although there are cameras that are more suited for in home use than others. Security camera technology has advanced so much recently that the versatility of security cameras for in home use is almost limitless.

Every home is different; the number of rooms in the home, the perimeter area that surrounds the home and the size of the home’s yard, the entrances and exits, number of windows, especially those on the ground floor – all vary from house to house. As every home’s design is different, so are the uses and needs for the security cameras for that home.

The most effective method to determine what security cameras for in home use are best for you is to evaluate your home design and your security desires and needs. After determining what you need to provide and the level of security and monitoring you desire, you can more easily begin the process of shopping for specific cameras that will satisfy those requirements.

Still, as stated earlier, there are security cameras for in home use that are more suited for this application than others. For an obvious example, an explosion proof camera or housing would be a ridiculous and unnecessary expense for in home use. However Security Camera King offers several different indoor security cameras that are perfect for in home use.

One way to narrow down your camera choice is to determine if you will be able to run the video transmission cable from each camera to the processor/DVR or Digital Video Recorder or if you would prefer a wireless camera instead. Cabling is the least expensive and the most common option for connecting the digital video camera to the DVR.

However, if installing the RG59 coaxial cable would be troubling for you, or if the cable would seem unsightly, or for any other reason the cable would not be right for you, wireless cameras would be the appropriate selection. Wireless cameras still require electrical power supply, normally in the form of a small wire run to the camera from a plug-in transformer or power distribution box. There are some wireless cameras that use rechargeable batteries as well.

Wireless cameras make use of radio technology to broadcast their video data to a corresponding receiver which then transfers the signal to the DVR. So a receiver is also needed if you choose the wireless camera option. Most receivers can handle up to four cameras at one time so if your system requires more than four cameras additional receivers (or a receiver that can handle more than four cameras) will be needed.

Regardless of whether you use cable or wireless technology, there are several different security cameras for in home use based on appearance, mounting design, and function. There are basically three types of cameras based on appearance. They are the box, bullet, and dome types, with each name representing a description of the appearance of the camera.

Each type has its own benefits and deficits. The box camera is probably the most common style of video camera but can also be somewhat obtrusive mounted on a room wall. The bullet type is also popular, but this type of camera usually lends itself to weatherproofing and infrared technology geared toward the outdoors. So if the box and bullet types are not appropriate for your application, then the dome type camera would probably be the best choice.

Dome cameras are fairly low-profile cameras with many available as a flush mount. Flush mounted dome cameras are installed in the wall or ceiling with only the “bubble” cover extending away from the surface. Security Camera King offers several different types of indoor dome cameras based on use and resolution display. That includes total darkness capable night vision infrared dome cameras as well.

Another category of security cameras for in home use include the hidden or disguised camera types. The cameras are embedded inside clocks, thermostats, and other everyday items to disguise their appearance.

To determine what camera is best for you, talk to one of our security experts today.

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