Dolby Laboratories DP569 User Manual

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Model DP569 User’s Manual 
A–1 
Appendix A 
Metadata 
Metadata provides unprecedented capability for content producers to deliver the 
highest quality audio to consumers in a range of listening environments. It also 
provides choices that allow consumers to adjust their settings to best suit their 
listening environments.  
In this appendix, we first discuss the concept of metadata: 
•  Metadata overview 
We then discuss the three factors controlled by metadata that most directly affect the 
consumer’s experience: 
•  Dialogue level 
•  Dynamic range control (DRC) 
•  Downmixing 
We then define each of the adjustable parameters, and provide sample combinations: 
•  Individual parameters 
•  Metadata combinations 
A.1 Metadata 
Overview 
Dolby Digital and Dolby E are both bit-rate reduction technologies that use metadata 
to describe the encoded multichannel audio. In normal operation the encoded audio 
and metadata are carried together as a data stream on two regular digital audio 
channels (AES/EBU or S/PDIF). Metadata is carried in the Dolby Digital or Dolby E 
bitstream, describing the encoded audio and conveying information that precisely 
controls downstream encoders and decoders. Metadata allows content providers 
unprecedented control over how original program material is reproduced in the home.  
Dolby Digital is a transmission bitstream (sometimes called an emission bitstream
intended for delivery to the consumer. It consists of a single encoded program of up 
to six channels described by one metadata stream. The consumer’s Dolby Digital 
decoder processes the metadata stream according to parameters set by the program 
creator, as well as certain settings for bass management and dynamic range that are 
chosen by the consumer to reflect their specific home theater equipment and 
environmental conditions.  
Dolby E is a distribution bitstream capable of carrying up to eight channels of 
encoded audio and metadata. The number of programs ranges from one single