We are an electronic security surveillance dedicated company concerning CCTV and linking customers to quality organizations who can meet their specific requirements. Realizing that the average person, when they begin to look into CCTV, have little way of knowing where to find expert advice, we have set up this web site to bring closer to our customers. Through this web site, we are often able to offer several free services to those who are seriously considering the installation of CCTV. We offered services include site surveys, drawing up plans, budget costing and system design. we are able to provide equipment on a supply-only basis to other customers around the country.
It is true that almost anyone can look at a location and suggest a number of Cameras. However, those who have experience in this field, through an understanding of the principles of optical science, will generally be able to give the customer a picture with much better definition. Often it is possible to give clients "added value" by locating Cameras, and utilising lenses which are able, not only to view the area of concern, but also give peripheral vision of other points of interest. A very simple example of the above is that one company may provide a view of everyone entering through a door while another may also incorporate an overview of the room the person is entering without any increase in cost or equipment. In many cases, careful questioning reveals that a picture of people leaving rather than entering the area may, in fact, provide much more valuable evidence in the event of a crime.
IP surveillance technology has reached one of those "perfect storm" moments. Today's digital cameras are inexpensive and easy to install. Wired and wireless networks alike are ubiquitous. And the camera-monitoring software is robust, easy-to-use and often free.
some companies will be looking to build dedicated systems that have guaranteed bandwidth and quality of service (QoS) over the video network. You can find them at retail businesses, factory floors, homes, apartments, landmarks, schools, financial institutions and transportation centers, to name but a few. Applications range from basic security and safety to quality control monitoring.
Although you can use these cameras over the Web, they're not really Webcams, which are those small, low-tech cameras designed for online socializing. Rather, IP-based cameras connect directly to IP networks, record at higher frame rates, and generally have better resolution then Webcams. They can pan, tilt and zoom, and many have one-way or two-way audio capabilities. They also come with monitoring and management software that lets you trigger alarms and e-mail alerts when certain events occur. For example, you can designate motion detection areas within a frame that generate alerts when motion occurs. Or you can set the system to begin recording when certain events occur or timers are set. Examples of motion events might include a person walking into the frame or a car driving across a designated area.
Since these systems are IP-based, you can monitor, store, and archive video, audio and associated application data over the Internet or across private data networks. The video can be carried anywhere the IP network extends, as opposed to closed-circuit television (CCTV) systems that require proprietary equipment and dedicated coaxial cabling. Anyone with the proper security clearance and a standard browser can monitor video, and control and configure the cameras on the network.
You need to have a fairly robust wired or wireless network set up for a successful IP surveillance roll-out. that you have a typical 10/100 wired wireless network already set up. We will, however, look at some Power over Ethernet (PoE) networking equipment and discuss the advantages of that type of system as well. PoE allows you to send power over ethernet lines so you don't have to place the cameras near power sources.
A quick rundown of the main benefits of IP surveillance follows
Let's get into the two main areas of components—the cameras and the network—that we'll need for building out an IP camera surveillance system.
Charge-Coupled-Device-Sensors capture the charges produced by light. Line by line the charges are transported through the sensor to an output node where they are converted to an analogue signal.
Complementary-Metal-Oxide-Semiconductor-Sensors also collect photogenerated charge. Each single pixel has an integrated complementary transistor circuit which amplifies the signal and assigns a digital value.
This technology enables the integration of complex circuitry on the sensor. If camera functions are implemented, each pixel can be optimised regarding e.g. brightness, range of contrast and white balance.
Smear effect means that a bright vertical line originating from a bright light source appears in the image, this happens especially with back lighting.
Because of the way the data is read out, this effect only occurs with CCD sensors. The charges on the sensor are shifted line by line to the bottom of the sensor, where they are read out consecutively. During the movement of lines across the sensor, the electrical charges passing the bright light source are exposed and so raised. Thereby a vertical, white stripe is formed within the picture.
With CMOS sensors this effect can not happen as the charge is read out directly from the pixel itself.
The 'blooming' effect only appears with CCD sensors as well.
By strong light exposure within a small pixel area more electric charge is produced than can be held by just one pixel. The excess charge is emitted to the adjoining pixels. Likewise these pixels can only hold a certain quantity of charges and so emit the surplus again. This leads to a saturation of charges on the sensor and so to overexposed picture areas.
The portion of light visible to the human eye lies in a wavelength range from approx. 380 to 780 nano metres (nm), whereas the infrared light (IR radiation) lies in a wavelength range from the visible light (780nm) up to the long wave rays. Infrared light is not visible to the human eye.
For daylight mode: The infrared light has an interfering effect on the image quality of the camera, leading to corruption of colours and contrasts as well as blurring. For night mode: In night mode, the infrared light is used to achieve detailed images in darkness or with low ambient light.
In order to avoid unwanted side-effects caused by infrared light (as part of the natural ambient light) during image recordings in daylight mode, an IR Cut Filter is installed in front of the sensor. The filter is meant to prevent the incidence of light onto the image sensor. Also, there is the IR Cut coating. This method realises the IR Cut Filter by applying a special coating to the lens.
(ICR = IR Cut Filter mechanically removable)
Through the use of the ICR function a real* Day/Night functionality of the camera can be realised.
Using a so-called filter shifter, the IR Cut Filter can be swivelled in, which means that in day mode the IR Cut Filter is moved in front of the sensor in order to block out the interfering infrared light. In night mode the IR Cut Filter is moved away so that IR light may pass through.
With IR corrected optical assembly, the lens is developed and manufactured so that the IR radiation is corrected before hitting the sensor.
This means that in daylight mode, IR corrected lenses also need an IR Cut Filter. Since even the best IR Cut Filters are not able to block all the IR radiation, the remaining IR rays that strike the sensor are corrected, hence an optimal image quality can be achieved. NOTE: Only IR corrected lenses are suitable for use with IR lighting!
* There are cameras with an electronic (virtual) Day/Night functionality. Thereby, switching from day to night mode is only done virtually by adjusting some parameters of the AE (»Automatic Exposure«) Presets. The image is displayed in black and white. The IR Cut Filter cannot be removed on cameras with electronic Day/Night function. Therefore, the filter blocks out the IR light in night mode, when it is actually needed.
Adobe* Flash* Player is required to display the film above. The necessary browser plug-in can be here. A click on the button “get Adobe* Flash* Player” above takes you right to the Adobe* download centre.
Please note that you may possibly not dispose of the necessary rights to install a plug-in if logged on to your PC as user. Security measurements such as firewalls in company networks may prevent plug-ins to be installed. If you cannot install the plug-in, please contact your system administrator.