Dolby Laboratories DP564 - Manual (Page 90)

DP564 Multichannel Audio Decoder Appendix A: Metadata
A-20
Because the revised definitions affect metadata parameters that were not used by the
consumer decoders, all decoders will be compatible with the revised bitstream. Newer
decoders that are programmed to detect and decode the new parameters will be able
to implement the new features the Extended BSI provides.
Products that allow emulation of the effects of metadata, such as the DP570, normally
have a feature that allows emulation of a new (or compliant) decoder or a legacy
decoder.
Preferred Stereo Downmix Mode
This parameter allows the producer to select either the Lt/ Rt or the Lo/Ro downmix
in a consumer decoder that has stereo outputs. Consumer receivers are able to
override this selection, but this parameter provides the opportunity for a 5.1-channel
soundtrack to play in Lo/Ro mode without user intervention. This is especially useful
on music material.
Preferred Stereo Downmix Mode
Setting
Not Indicated
Lt/Rt Preferred
Lo/Ro Preferred
Lt/Rt Center Mix Level
This parameter indicates the level shift applied to the center channel when adding to
the left and right outputs when downmixing to an Lt/Rt output. Its operation is similar
to the center downmix level in the universal metadata.
Lt/Rt Center Mix Level Setting
1.414 (+3.0 dB)
1.189 (+1.5 dB)
1.000 (0.0 dB)
0.841 (–1.5 dB)
0.707 (–3.0 dB)
0.595 (–4.5 dB)
0.500 (–6.0 dB)
0.000 (–999 dB)