eLine Technology iVMS-2000 V2.0.2 - Manual (Page 112)

iVMS-2000 User Manual
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The whole monitoring image is divided into various small areas, among which users can
select any areas with different sensitivity level, and the movements in these areas will be
detected by the camera and trigger motion record.
Video Tamper Alarm
Alarm when video being tampered
Privacy Mask
Mask certain area of the image.
Pre-record Time
Save recording in a short duration before the scheduled start time
Post-record Time
Save recording in a short duration after the scheduled start time
Bit Rate
Bit rate is the bit number per unit time in data transmission, usually using the unit of
kbps (kbit per second), or to say, the sampling rate. The highest the sampling rate per unit
time, the more precise the data information, and the more close the transmitted file to the
original file. But the file size will increase as the sampling rate increases, thus almost all the
encoding standard is focus on acquiring least distortion with smallest video size, and the CBR
(Constant Bit Rate) and VBR (Variable Bit Rate) is originated from it. On the side of audio
encoding, the higher the bit rate, the less the compression ratio and sound distortion, but the
encoding algorithm is different for different audio players, and the bit rate is not the only
measure for audio quality. For instance, it is not exactly that the sound quality of lower bit
rate mp3 files is not as good as higher bit rate wma file, especially after using VBR encoding.
In some occasions, VBR can even achieve better audio quality than CBR on the same encoder.
Stream Type
Compressed stream type containing both video stream and video & audio stream.
Video & Audio Stream
Multimedia stream that contains both video and audio information
Video Stream
Pure video stream
Video Frame Rate
Video frames per second
Frame Rate
FPS, stands for frames per second, the value of information data flow of dynamic images.
Continuous playing of static images will enable the feeling of dynamic video, and the
movements will be much fluent as fps value raises.
Frame Type
I frame (Intra code frame) is intra-frame encoding frame, P(Predicted frame)is forward
forecast coding frame according to I or the previous P frame, B(Bi-direction frame)is
interpolation frame calculated by neighboring I, P or P, P frames.
Dual Stream
It means a camera of video images passing through the video coder, and output 2
independent bit streams. The resolution, frame rate, bit rate and other parameters of output
bit stream can be set independently. The output dual steam can meet different demands, for
example, one for hard disk storage and the other for network transmission.
Watermark
It means to insert hidden information, i.e. digits, serial number, characters, logo, etc
into digitalized multimedia files by signal processing technology. Such marks are usually
invisible, and can only be extracted by specially designed detectors to get the purpose of
copyright protection.
TV Wall
TV wall is formed by i ntegration of multiple display units. A large-screen TV wall system
is consisted of TV wall units, TV wall processor and TV wall interfaces. Generally speaking,
any display unit can be adopted to TV wall system. TV wall processor can do image processing
(divide and enlarge) to a complete standard video input signal and output to M*N standard
display devices, and the TV wall interfaces is device for signal transforming and output
between signal input and TV wall output.
Resolution
Resolution types include display resolution, image resolution and pixel resolution.
Display resolution is the largest area shown on the screen in particular display mode, in