Cobalt Digital COMPASS 9223-SA Dual-Channel 3G_HD_SD MPEG-4 Encoder Unit - Manual (Page 29)

29
9223SA-OM (V2.0)
•
Video Bit Rate: This field is shown only if the encoder is set to CBR mode and the Bit
Rate Selection control is set to Video Bit Rate. It determines the video elementary
stream bit rate, expressed in bits/second. Note that the bit rate resolution is
1000 bits/second.
•
Transport Bit Rate: This field is shown only if the encoder is set to CBR mode and the
Bit Rate Selection control is set to Transport Bit Rate. It determines the overall
transport stream bit rate, with a resolution of 1000 bits/sec; the encoder will calculate the
appropriate video bit rate the yield the desired transport rate. Please note that all
transport rates are achievable; in particular, the encoder may not be able to achieve very
low transport rates if the audio bit rates are high. In these cases, the actual transport rate
output by the encoder will be higher than the configured value. The actual transport rate
is displayed in the Encoder Statistics Tab, after the Apply button has been pressed. At
that point, the actual encoder video bit rate can be found in the Encoder Statistics Tab,
under the Basic bottom tab.
•
Peak Video Bit Rate, Average Video Bit Rate: These two fields are shown only if the
encoder is set to VBR mode, and determine the desired average and acceptable peak bit
rates for the video elementary stream. The peak video bit rate must be between 2.0 and 2
times the average bit rate; the user interface will enforce these limits automatically (i.e., it
will update either the average or peak to be consistent with the value being entered). For
both of these parameters, the resolution is 1000 bits/sec.
Basic Tab – Audio Configuration
•
Audio Source: This parameter selects the audio source. The options are Analog Audio,
directing the encoder will to use the analog right/left audio channels connected to the rear
panel, and SDI Embedded Audio, directing the encoder to extract embedded audio from
the SDI input. If the video Input Source (see Basic Tab – Video Configuration) is set to
Composite, this parameter is grayed out and forced to Analog Audio. It will be
selectable only if the video input source is one of the SDI variations. When SDI
Embedded Audio is selected, additional configuration options become available, as
shown below.