RE: Audio Digital Data Streams

["Mark Harrison" <Mark.Harrison@xxxxxxx>]

The following multi-channel formats are carried natively digital, and
include tagging to specify which format they're in. In addition, they
carry further tags to specify how many discrete audio channels are
included. Dolby Digital, for example, has several different varieties,
between mono and 6 channels (5 full-frequency, plus 1 limited bandwidth
intended for Bass.)

- Dolby Digital (between 1 and 6 discrete channels)
- DTS (between 1 and 6 discrete channels)
- MLP (between 2 and 6 discrete channels, I think??????????)

The following multi-channel formats are carried natively analogue, on
two channels, and don't include any tagging. They just rely on phase
processing to try to "decode" a rear channel.

- Stereo
- Dolby Surround (three channels modulated into two)
- Dolby Pro-logic (four channels modulated into two)


The real expert on all of this is Phil Harris.

Mark Harrison
Head of Systems, eKingfisher

-----Original Message-----
From: Kevin Hawkins [mailto:lists@xxxxxxx]
Sent: 26 March 2002 16:24
To: UKHA Group
Subject: [ukha_d] Audio Digital Data Streams


Is all the info necessary to define the exact format of the data
encoding always transmitted in an audio digital data stream or is it
sometimes ambiguous ?
Specifically with ITV Digital (assuming it is still around by the
time you read this), do they ever transmit anything apart from standard
stereo or Dolby Surround ? (I heard not as they don't have the
bandwidth). When they do transmit Dolby Surround is there anything in
the data stream so that you know it is in surround rather than ordinary
stereo ? I do have a digital output from my Nokia ex OD box.

Kevin