In principle, anywhere you consider necessary. Modern systems are extremely flexible and can be configured and controlled individually. Outdoor installations are also possible and unproblematic thanks to weatherproof housing and integrated heating.
It is recommended to install the cameras at a sufficient height above the ground in order to prevent unauthorised access and manipulation. If this is not possible, vandal-proof dome cameras with a robust, unbreakable housing are a good choice.
You have the right to know what's happening in your company at all times. You must inform your employees about the installation of one or more camera. In the case of shops, there must be an corresponding notice on the entrance door. It goes without saying that certain rooms such as toilets are excluded from surveillance to safeguard privacy.
Your old analogue cameras as well as new digital cameras can be connected to a modern, PC based video surveillance system. This can keep costs down and you don't have to remove your old devices. In any case, such a “hybrid system” is future-oriented.
Wireless transmission systems are used wherever laying cables is impossible or not wanted. Transmission is free of charge on the high frequency radio band with 2.4 or 5.8 GHz. High-quality systems make wireless ranges of up to 2,200 meters outdoors or 125 meters indoors possible. Up to nine radio transmitters can be operated simultaneously within an object.
Good video cameras are equipped with an automatic switching function from colour to black/white mode. When the light intensity falls below a certain value, the camera switches over automatically enabling it to take video pictures even in the dark.
Certain cameras can also be used with infrared light. An infrared illuminator emits light invisible for the human eye and makes it possible to provide good pictures even when it is completely dark.
Quad-stream (literally “four stream”) means the simultaneous transmission, and therefore the simultaneous output, of four different video data formats. This usually means MPEG4, MJPEG, H.264 and 3GPP formats. Thanks to the four parallel live streams, the right stream can be selected for the bandwidth or for the technology of the device (for example, low resolution for viewing on a smartphone, as opposed to high resolution screens). This saves bandwidth with mobile data transmission but also enables finely-detailed high resolution on the display devices.
If you have constantly changing light conditions, use an auto iris lens. It adjusts the iris automatically to light conditions and always guarantees optimally exposed pictures.
Network cameras (also known as “IP cameras”) transfer the image data directly into the network and are controlled directly via a network address (IP address).
As well as the camera module, ABUS network cameras also have a web server which takes care of compressing and sending the data within the network.
With an autofocus camera, the lens automatically focuses on an object. If there is a person between the object and the camera, it automatically focuses on the person.
Whether miniature, built-in or underwater camera – ABUS video servers also bring video and audio streams into the network fast and easily. In this way, you save a time consuming new installation as well as the need to purchase a new camera and can enjoy fascinating pictures independent of time and place.
That means: Live pictures with sound can be downloaded worldwide by mobile phones. At the same time, the image data is stored with high resolution on your computer using the recorder software.
Compressing video data reduces the size of files containing video films to make data transmission faster and reduce the space required to store the file in comparison with the uncompressed video format. There are different compression methods; the most commonly used are MPEG and MJPEG.
Examples of compression:
MPEG compression is based on the principle that in a video file, large parts of consecutive images are identical and do not have to be saved in their entirety for every picture. The MPEG codec forms so-called image groups in which the first key picture is saved exactly and the following ones are interpreted. This makes significant data compression possible, but only the key images can be cropped.
With MJPEG compression (= Motion JPEG) on the contrary, each individual image is compressed with JPEG irrespective of the movement. This means that a video clip is coded as a sequence of JPEG images and any image can be cropped. The video recording is high quality and, at 3 MB/sec, corresponds roughly to S-VHS. Most digital video cameras use the MJPEG standard.
Other compression formats are e.g.:
MPEG-1, MPEG-2 and MPEG-4, H.263, H.264/AVC among others.
Pictures from analogue and network cameras can be recorded on a recorder. Up to 40 cameras can be connected in one system. The video images can be viewed, replayed, recorded and fed into the network at the same time. The maximum length of the recording depends on the image quality, the number of cameras installed and the size of the hard drive. (See also “What is video compression?”)
TFT monitors work with thin film transistors, hence the abbreviation TFT. These are special field-effect transistors with which large-area electronic circuits can be produced. The picture is produced when the laser meets the thin silicon layer.