Siqura C-60 E-MC, Руководство пользователя

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Siqura C-60 E-MC
Page 56
Encoder Settings
Note: The C-60 E-MC will simultaneously handle H.264 encoding and dual
MPEG-2/4 encoding at full frame rate, and Live View encoding at 5 frames
per second. Setting Encoders 1 and 2 to perform MPEG-2/4 encoding in D1
resolution at the same time may overtax the hardware. The total output
bandwidth, including streams controlled by RTSP, and those enabled
through SAP, should not exceed 25 Mb/s.
GOP length Distance in frames between two I-frames.
Frame rate Selectable rates are determined by the video mode (PAL, NTSC) set on the General
tab. PAL: 1-25 fps; NTSC: 1-30 fps.
Bit rate Range: [56...6000]. Available in Constant bit rate non-drop mode. The speed of the
digital transmission, that is - the amount of information transferred/processed per unit
of time.
Actual bit rate Available in Constant quality mode (CQM). This field is dynamically updated with the
current bit rate to provide feedback on the bit rate that is used on average with the
current Quality setting (see below).
Quality Available in Constant Quality Mode (CQM). Reflects the amount of compression.
Generally speaking: the higher the quality setting, the lower the compression ratio
and the more bits are consumed. This means a trade-off has to be found between the
desired quality level and available bandwidth.
Profile Preset combinations of settings for specific purposes. When a profile has been
selected, changing one of its defined parameters sets the Profile box to '--', to indicate
that a custom profile has been configured. When a freely chosen parameter value
combination matches a preset profile, the name of the profile shows in the Profile box.
Show Preview>> Click to view live images and see the effect of the current settings.
<<Hide Preview Hiding the preview may improve web page responsiveness.
Volume Drag the sliding button to control audio volume.
Mute Select or clear this box to respectively mute or unmute audio.
Note on CIF resolutions:
CIF resolutions (2CIF, CIF, QCIF) use only one of the two frame fields.
When CIF-encoded pictures are displayed on a monitor, the decoder simulates the second field
(by extrapolation from the first field) in order to present two frame fields. CIF is mostly used for
recording purposes, as a compromise between good video quality and storage capacity needed.
Constant Quality Mode (CQM) configuration
Constant Quality Mode can be used in situations with intermittent increases of movement in
camera images. This mode provides better pictures when quickly panning a PTZ camera, for
example. Siqura recommends the following strategy for CQM configuration.

To configure Constant Quality Mode settings
1. In Encoder Settings, open the
Video bit rate mode
list and select
Constant quality
.
2. With the video source connected and the H.264 encoder enabled, go to the Quality field and
set the desired quality (range: [0 ... 100%]), aided by the visual feedback in the Preview.
3. Press Save to store your settings.
The Actual bit rate field is dynamically updated with the current bit rate.
4. Determine if the average bit rate used with the current Quality setting is acceptable. If not,
modify the Quality setting.
5. To set the upper limit for the bit rate, open the
Advanced Settings
section and use the CQM
max bit rate field to specify the maximum bit rate.
Generally, it will not be necessary to change the default setting of 6000 kbit/s, unless there
are physical limitations on the network.
6. Press
Save
to store your settings.