Manual

Encoding tool and conversion metadata
A bitstream contains metadata generated by coding tools as well as metadata values that
enable a decoder to convert a Dolby Digital Plus bitstream to Dolby Digital without fully
decoding it.
Multiple downmix options
A bitstream can carry downmix coefficients for stereo, Dolby Surround compatible, and
Dolby Pro Logic II compatible downmixes.
2.1.4 Dolby Digital features
Because Dolby Digital Plus is built on Dolby Digital, they share a number of features.
These Dolby Digital features are also part of Dolby Digital Plus:
Dialogue normalization
Dialogue normalization is the process of aligning the average dialogue level of different
programs to a consistent level (the dialogue reference level) so that a consumer does not
have to constantly adjust the volume control of the playback system as programs change.
Dynamic range control
Dynamic range control compresses the dynamic range of a program by reducing (cutting)
the level of the loudest sounds and increasing (boosting) the level of the quietest sounds to
adjust the sound to the listening situation.
Audio production information
Audio production information is additional information about the audio production
environment, such as the mixing level, recording room type, and copyright information.
Dolby Digital also supports two types of two-channel downmix: Dolby Surround compatible
(Lt/Rt) and stereo (Lo/Ro). In Dolby Digital decoders, when 2.0 output is selected and LFE output
is disabled, the LFE channel content is not reproduced.
2.1.5 Dolby ED2 features
Dolby ED2 extends Dolby E in many dimensions. The expanded capabilities enable greater
broadcast flexibility and better end-user experiences.
Dolby ED2 includes these features:
Greater number of AES3 stereo pairs
The maximum number of pairs is increased from two to four.
Greater number of audio elements (channels or objects)
The maximum number of elements is increased from 8 to 16.
Different use for program configurations
Dolby E provides 24 channel-based configurations, whereas Dolby ED2 configurations are
restricted for personalized and immersive use cases.
Dolby E and Dolby AC-3 metadata parity
Metadata for both the contribution format and the codec remain accessible.
2.2 New features
This release of the Dolby Professional Reference Decoder DP580 adds new functionality
included with the latest Dolby codecs and contribution formats. Later releases may carry
additional functionality for broadcast environments.
Overview of the Dolby Professional Reference Decoder DP580
Dolby Professional Reference Decoder DP580 v2.0 user's guide
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