Grass Valley Imagestore 750 v.3.0.1 - Manual (Page 136)

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Advanced Audio
Dolby
Please see Dolby Digital Encoder Module on page 116 for a description of each mode.
Dolby Metadata
Dolby metadata contains information about the audio bit-stream. It is different for Dolby Digital
and Dolby E.
• Dolby E metadata contains a copy of the Dolby Digital metadata for every program carried in
the transport stream, as well as parameters specific to the transport stream such as what
audio configuration of programs is being carried, for example 5.1 + 2.
• Dolby Digital metadata contains data to be used by consumer electronics, such as mix levels
for down-mixing surround sound into stereo.
Metadata can accompany the audio input into an Imagestore 750 and be routed though to
output, or it can be supplied separately for use directly at the audio outputs. Metadata is
routed through the Imagestore 750, connected between various metadata sources and des-
tinations. Metadata may be carried with the audio within an SDI or AES transport or sepa-
rately on a RS-485 serial connection.
The Imagestore 750’s metadata handling includes:
• A/B switching of metadata synchronously with the audio A/B-mixer.
• RS-485 serial metadata connections, flexible inputs and outputs.
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• Custom-defined metadata presets.
• Internal metadata generation from selectable custom-defined presets.
• Changing internally-generated metadata through automation.
• Flexible routing of metadata internally.
Program Configuration
Each Dolby decoder and encoder processes up to 8 mono audio channels. A “program configu-
ration” contains a set of audio “programs,” each of which contains a number of audio “channels.”
For example, the program configuration “5.1 + 2” comprises two audio programs, 5.1 surround
and stereo, with a total of eight audio channels.
2. Please refer to Rear Panel and Connections on page 200 for details of the RS-485 ports.