Manual

2.1.2 Dolby Atmos
Dolby Atmos is an object-based audio technology for creating and reproducing spatial audio.
The Dolby Atmos platform encompasses products, services, and technologies and includes
authoring, distribution, and playback tools for both linear and nonlinear content.
Rather than require a content creator to downmix the individual elements (objects) of an audio
scene to a fixed number of output channels prior to transmission and rendering, individual
audio objects can be preserved, transmitted, and rendered individually. Key features of
Dolby Atmos include:
•
Object-based audio metadata encoded in the audio bitstream
•
Three-dimensional audio rendering
•
Device-independent audio bitstreams that can be faithfully rendered by any Dolby Atmos
playback device
•
A flexible rendering engine for Dolby Atmos playback devices that supports a wide range of
loudspeaker layouts and room characteristics
•
New speaker positions and designs
Dolby Atmos supports dynamic objects as well as traditional channel-based audio. Dynamic
objects are used for discrete sound elements that can be precisely placed and moved through
the playback environment, such as a helicopter that flies over the audience. Channel-based
audio is often used for static ambient sounds, such as the music portion of a soundtrack. A
typical Dolby Atmos soundtrack is a combination of dynamic objects and bed objects (channels)
collectively referred to as object-based audio.
2.1.3 Dolby Digital Plus features
Dolby Digital Plus introduces a number of enhancements to Dolby Digital, including support for
a wider range of data rates, increased channel count, multiple-program support, and additional
tools for representing compressed data and eliminating artifacts. Dolby Digital Plus is backward
compatible with Dolby Digital.
Dolby Digital Plus includes these features:
High data rate
Supports a maximum data rate of 6,144 kbps.
Uses a variable frame duration (one, two, three, or six audio blocks per frame) to
accommodate high data rates.
Scalable bitstream structure
A flexible structure of multiple independent and dependent substreams supports additional
programs and additional channels.
Multichannel support
Supports up to 7.1.4 channels in a single program and up to two independent Low-
Frequency Effects (LFE) channels.
Multiple audio programs
A single bitstream can contain up to eight audio programs.
Mixing metadata
A bitstream can carry mixing metadata for receiver mixing of two streams (for example, to
support service).
Overview of the Dolby Professional Reference Decoder DP580
Dolby Professional Reference Decoder DP580 v2.0 user's guide
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