Vicon V992B-IR4, Руководство по установке

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4.2 Video
The following descriptions show examples of some of the features available with V992D-N4.
4.2.1 Codec
This section allows you to choose the compression codec for each of the video streams.
Codec
H.264
This is a video compression standard that makes good use of bandwidth and could
provide high-quality video streams.
The H.264 standard provides the scope for a large range of different coding tools for use
by various applications in different situations, and the V992D-N4 provides certain
subsets of these tools.
Using H.264, it is also possible to control the bit rate, which in turn allows the amount of
bandwidth usage to be controlled. CBR (Constant Bit Rate) is used to achieve a specific
bit rate by varying the quality of the H.264 stream. While using VBR (Variable Bit Rate),
the quality of the video stream is kept as constant as possible, at the cost of a varying bit
rate.
Motion JPEG
This format uses standard JPEG still images in the video stream. These images then are
displayed and updated at a rate sufficient to create a stream that shows constantly
updated motion.
The Motion JPEG stream uses considerable amounts of bandwidth, but also provides
excellent image quality and access to every individual image contained in the stream.
Multiple clients accessing Motion JPEG streams could use different image settings.