Vicon CE102D, Руководство по установке

Страница: 19 / 71

19
* MPEG4 SP (Simple Profile):
Mostly aimed for use in situations where low bit rate and low resolution are mandated by
other conditions of the applications, like network bandwidth, device size, etc.
- Resolution:
Resolution enables users to determine a basic screen size when having access through the
Web Browser or PC program. The screen size control comes in several modes, such as
1920x1080, 1280x1024, 1280x720, 800x600, 704x480 (576), 640x480, 352x240 (288) and
320x240. Users can reset the selected screen size anytime while monitoring the screen on a
real-time basis.
- Bitrate
control:
The bit rate can be set as Variable Bit Rate (VBR) or Constant Bit Rate (CBR). VBR adjusts
the bit rate according to the image complexity, using up bandwidth for increased activity in
the image, and less for lower activity in the monitored area.
CBR allows you to set a fixed target bitrate that consumes a predictable amount of
bandwidth. As the bit rate would usually need to increase for increased image activity, but in
this case cannot, the frame rate and image quality are affected negatively. To partly
compensate for this, it is possible to prioritize either the frame rate or the image quality
whenever the bit rate needs to be increased. Not setting a priority means the frame rate and
image quality are equally affected.
- Bitrate:
When it is necessary to adjust a smooth transmission status according to network situations,
users can increase the compressibility to carry out the network transmission stably.
Alternatively, when it is necessary to maintain a detailed monitoring screen by enhancing
the image quality, users can do so by decreasing the compressibility. In each case, adjust
this function according to the network status and monitoring purposes. The default is 2000
(Kbps).
- Frame
rate:
Upon the real-time play, users should select a frame refresh rate per second. If the rate is
high, the image will become smooth. On the other hand, if the rate is low, the image will not
be natural but it can reduce a network load.
- GOP size:
Select the GOP (Group of Picture) size. If users want to have a high quality of fast image
one by one, decrease the value. For the purpose of general monitoring, do not change a
basic value. Such act may cause a problem to the system performance. Vicon recommends
that GOP be the same as the fps.