Axis Network video Manual page 9

NETWORk VIDEO: OVERVIEW, BENEFITS AND APPLICATIONS - CHAPTER 1
location to view and manage video, and off-site video access would not be possible without
such equipment as a video encoder or a network digital video recorder (DVR). A DVR is the
digital replacement for the video cassette recorder.
> High image quality: In a video surveillance application, high image quality is essential to
be able to clearly capture an incident in progress and identify persons or objects involved.
With progressive scan and megapixel technologies, a network camera can deliver better
image quality and higher resolution than an analog CCTV camera. For more on progressive
scan and megapixel, see chapters 2, 3 and 6.
Image quality can also be more easily retained in a network video system than in an analog
surveillance system. With analog systems today that use a DVR as the recording medium,
many analog-to-digital conversions take place: first, analog signals are converted in the
camera to digital and then back to analog for transportation; then the analog signals are
digitized for recording. Captured images are degraded with every conversion between analog
and digital formats and with the cabling distance. The further the analog video signals have
to travel, the weaker they become.
In a fully digital IP-Surveillance system, images from a network camera are digitized once
and they stay digital with no unnecessary conversions and no image degradation due to
distance traveled over a network. In addition, digital images can be more easily stored and
retrieved than in cases where analog video tapes are used.
> Event management and intelligent video: There is often too much video recorded and lack
of time to properly analyze them. Advanced network cameras and video encoders with built-
in intelligence or analytics take care of this problem by reducing the amount of uninteresting
recordings and enabling programmed responses. Such functionalities are not available in an
analog system.
Axis network cameras and video encoders have built-in features such as video motion detec-
tion, audio detection alarm, active tampering alarm, I/O (input/output) connections, and
alarm and event management functionalities. These features enable the network cameras
and video encoders to constantly analyze inputs to detect an event and to automatically
respond to an event with actions such as video recording and sending alarm notifications.
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