- Dolby Multichannel Audio Tool User's Manual

4 Dolby
®
DP570 Multichannel Audio Tool User’s Manual
Overview
TheCat.No.548AnalogOutputCardprovidesananalogmonitorsectionandsome
additionalfeaturestoeaseinterfacingtoexistingmixingandmonitoringenvironments.
Thisoptionalanalogmonitorsectionprovidesfeaturesincludingmultiple
speaker‐configurationoutputs,amastervolumecontrol,speakertrimcontrols,andan
inputforaconsole
solobus.
1.4 Main Applications
TheDP570can besuccessfullydeployedwhereverthereisaneedtomonitorthequalityof
digitalaudio,andtoreviewexistingmetadata.Itiscurrentlymostcommonintwo
applications:
•DVDmastering
• CreationandbroadcastofDTVcontent
1.4.1 Use in DVD Mastering
ADVDauthoristypicallypreparingmixedaudioforwritingtotheDVD:generating
metadata,verifyinglevels,andauditioningdownmixes.Thisprocessisdescribedindetail
inChapter 5.
1.4.2 Use in Digital Television
Here’sanexampleoftheprocessflowinDTV:
Inabroadcasttruckparkedoutsideafootballstadium,theprogrammixerchoosesthe
appropriatemetadatafortheaudioprogrambeingcreated.Theresultingaudioprogram,
togetherwithmetadata,isencodedasDolbyEdataandsenttothetelevisionstationvia
fiber,microwave,orothertransmissionlink.Thisprocessisdiscussedindetailin
Chapter 6.
Atthereceivingendofthistransmission,theDolbyEstreamisdecodedbacktobaseband
audioandmetadata.Theaudio programandthemetadataaremonitored,altered,or
re‐createdasotherelementsoftheprogram
areaddedinpreparationforbroadcast.This
processisdiscussedindetailinChapter 7.
Thisnewaudioprogram/metadatapair,reencodedasDolbyEdata,leavesthe
postproductionstudioandpassesthroughthetelevisionstationtoMasterControl,where
manyincomingDolbyEstreamsareonceagaindecodedbacktotheir
individualbaseband
digitalaudio/metadataprograms.Theaudioprogram/metadatapairthatisselectedtoair
issenttothetransmission DolbyDigitalencoder,whichencodestheincomingaudio
programaccordingtothemetadatastreamassociatedwithit,therebysimplifyingthe
transmissionprocess.ThisprocessisdiscussedindetailinChapter 8.
Finally,the
DolbyDigitalsignalisdecodedintheconsumer’shome,withmetadata
providingtheinformationforthatdecodingprocess.Throughtheuseofmetadata,the
mixerinthetruckhasbeenabletocontrolthehomedecoderforthesportingevent,while
segmentssuchasnewsbreaks,commercials,andstationIDs
aresimilarlydecoded,each
usingitsownmetadata.