Cobalt Digital COMPASS 9223-SA Dual-Channel 3G_HD_SD MPEG-4 Encoder Unit - Manual (Page 30)

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9223SA-OM (V2.0)
•
Group, Channels: SDI embedded audio is typically divided into four groups (denoted by
Group 1 to Group 4); each group has four mono channels (2 stereo pairs), denoted by
Channels 1-2 and 3-4. These controls allow the selection of the desired group and
channel pair. In the large majority of the cases, the first stereo pair is in Group 1,
Channels 1-2, the second stereo pair is in Group 1, Channels 3-4, and so on. The Group
selection has one additional choice, labeled Custom DID. This allows the encoder to use
a non-standard embedded audio DID (this quite uncommon). If Custom DID is selected,
a new configuration option becomes available, where the DID can be entered:
•
Group DID: Enter the desired Group DID, in hexadecimal. Note that the entry will be
immediately validated and rejected if invalid. As a reference, the table below contains
the standard DIDs built into the system for Groups 1 to 4.
Group SD-SDI DID HD-SDI DID
Group 1 0x2FF 0x2E7
Group 2 0x1FD 0x1E6
Group 3 0x1FB 0x1E5
Group 4 0x2F9 0x2E4
• Language Code: This parameter represents the 3-letter ISO 639-2 language code for the
audio, to be placed in the audio language descriptor in the PMT.
•
Audio Encoding: This parameter selects the audio encoding algorithm. The available
choices depend on the Audio Source selection. For Analog Audio, the choices are
MPEG-1 Layer II and AAC-LC. For SDI Embedded Audio, the Dolby Passthrough
option is offered in addition to the previous choices. Note that AAC-LC requires
additional licensing. The two variants for this control are depicted below.