Dolby Laboratories DP569 - Manual (Page 70)

Model DP569 User’s Manual Metadata
A–12
A.5.1 Universal Parameters
Universal parameters are present in all Dolby Digital encoders and decoders.
Dialogue Level
The Dialogue Level parameter is discussed in Section A.2.
Channel Mode
This parameter (also known as audio coding mode) indicates the active channels
within the encoded bitstream and affects both the encoder and consumer decoder.
This parameter instructs the encoder as to which inputs to use for this particular
program; it tells the decoder what channels are present in this program so the decoder
can deliver the audio to the correct speakers.
The setting is described as X/Y, where X is the number of front channels (Left,
Center, Right) and Y the number of rear (surround) channels.
The availability of certain channel modes depends on the data rate and whether the
LFE Channel is present. For example, you can’t have a mono stream with an LFE
channel (1.1!) or a 3/2 stream at 96 kbps. Appropriate data rates are shown in the
definition of each setting.
Note: The presence of the LFE channel is indicated through a different metadata
parameter (see LFE Channel).
Table A-3 Channel Mode Settingsd
Channel Mode
Setting
Definition and Data Rate
1+1
Dual mono (not valid for DTV
broadcast or DVD production)
1/0 Mono From 56 kbps, usually 96 kbps
2/0 Stereo From 112 kbps, usually 192 kbps
3/0 From 256 kbps
2/1 From 256 kbps
3/1 From 320 kbps
2/2 From 320 kbps
3/2 From 384 kbps, often 448 kbps
LFE Channel
The status of the LFE Channel parameter indicates to a Dolby Digital encoder
whether an LFE Channel is present within the bitstream. Channel Mode determines