Dolby Laboratories DP570 Line Mode Compression Profile and RF Mode Compression Profile , RF Overmodulation Protection

Parameter Definitions
Dolby® DP570 Multichannel Audio Tool User’s Manual 95
Line Mode Compression Profile and RF Mode Compression Profile
Fordetailsoftheavailableprofiles,seeSectionD.4.
RF Overmodulation Protection
ThisparameterisdesignedtoprotectagainstovermodulationwhenadecodedDolby
DigitalbitstreamisRFmodulated.Whenenabled,theDolbyDigitalencoderincludes
pre‐emphasisinitscalculationsforRFModecompression.Theparameterhasnoeffect
whendecodingusingLinemodecompression.Exceptinrarecases,thisparametershould
bedisabled.
MainM&E(ME) Thebitstreamisthemainaudioservicefortheprogram,minusa
dialoguechannel.Thedialoguechannel,ifany,isintendedtobe
carriedbyanassociateddialogueservice.Differentdialogueservices
canbeassociatedwithasingleMEservicetosupportmultiple
languages.
Assc.VisualImp.(VI) Thisistypicallyasingle‐channelprogramintendedtoprovidea
narrativedescriptionofthepicturecontenttobedecodedalongwith
themainaudioservice.TheVIservicemayalsobeacompletemixof
allprogramchannels,comprisinguptosixchannels.
Assc.HearImp.(HI) Thisistypicallyasingle‐channelprogramintendedtoconveyaudio
thathasbeenprocessedforincreasedintelligibilityanddecoded
alongwiththemainaudioservice.TheHIservicemayalsobea
completemixofallprogramchannels,comprisinguptosixchannels.
Assc.Dialogue(D) Thisistypicallyasingle‐channelprogramintendedtoprovidea
dialoguechannelforanMEservice.IftheMEservicecontainsmore
thantwochannels,theDserviceislimitedtoonlyonechannel;ifthe
MEserviceistwochannels,theDservicecanbeastereopair.The
appropriatechannelsofeachservicearemixedtogether(requires
specialdecoders).
Assc.Commentary(C) Thisistypicallyasingle‐channelprogramintendedtoconvey
additionalcommentarythatcanbeoptionallydecodedalongwith
themainaudioservice.Thisservicediffersfromadialogueservice
becauseitcontainsanoptional,ratherthanarequired,dialogue
channel.TheCservicemayalsobeacompletemixofallprogram
channels,comprisinguptosixchannels.
Assc.Emergency(E) Thisisasingle‐channelservicethatisgivenpriorityinreproduction.
WhentheEserviceappearsinthebitstream,itisgivenpriorityinthe
decoderandthemainserviceismuted.
Assc.Voice Over(VO) Thisisasingle‐channelserviceintendedtobedecodedandmixedto
theCenterchannel(requiresspecialdecoders).
MainSvKaraoke(K) Thebitstreamisaspecialserviceforkaraokeplayback.Inthiscase,
theLeftandRightchannelscontainmusic,theCenterchannelhasa
guidemelody,andtheLeftSurroundandRightSurroundchannels
carryoptionalbackingvocals.
Table D-7 RF Overmodulation Protection Settings
RF Overmodulation
Protection Setting
Enabled
Disabled
Table D-6 Bitstream Mode Options (continued)
Bitstream Mode
Setting Definition