Description

This use-case allows the listener to switch between different storylines. This is similar to the interactive multiple language use-case, but instead of switching between languages, the user switches between storylines.
Approach

The two storylines, 'Lesley' and 'Bill', are each represented by their own audioContents, which in turn each reference audioObjects that are complementary with each other. Below each of these two storyline complementary audioObjects are separate audioObjects for speech and ambient sound. There are also audioObjects that are common to both storylines.
Multiple storylines structure
Example XML

<?xml version="1.0" encoding="utf-8"?>
<ebuCoreMain xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns="urn:ebu:metadata-schema:ebuCore_2014" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" schema="EBU_CORE_20140201.xsd" xml:lang="en">
  <coreMetadata>
    <format>
      <audioFormatExtended version="ITU-R_BS.2076-1">
        <audioProgramme audioProgrammeID="APR_1001" audioProgrammeName="Programme" audioProgrammeLanguage="en">
          <audioContentIDRef>ACO_1001</audioContentIDRef>
          <audioContentIDRef>ACO_1002</audioContentIDRef>
          <audioContentIDRef>ACO_1003</audioContentIDRef>
          <audioContentIDRef>ACO_1004</audioContentIDRef>
        </audioProgramme>

        <audioContent audioContentID="ACO_1001" audioContentName="Lesley">
          <audioObjectIDRef>AO_1001</audioObjectIDRef>
        </audioContent>
        <audioContent audioContentID="ACO_1002" audioContentName="Bill">
          <audioObjectIDRef>AO_1004</audioObjectIDRef>
        </audioContent>
        <audioContent audioContentID="ACO_1003" audioContentName="Intro Narrator">
          <audioObjectIDRef>AO_1007</audioObjectIDRef>
        </audioContent>
        <audioContent audioContentID="ACO_1004" audioContentName="Intro Music">
          <audioObjectIDRef>AO_1008</audioObjectIDRef>
        </audioContent>

        <audioObject audioObjectID="AO_1001" audioObjectName="Lesley">
          <audioObjectIDRef>AO_1002</audioObjectIDRef>
          <audioObjectIDRef>AO_1003</audioObjectIDRef>
          <audioComplementaryObjectIDRef>AO_1004</audioComplementaryObjectIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1002" audioObjectName="Speech">
          <audioPackFormatIDRef>AP_00031001</audioPackFormatIDRef>
          <audioTrackUIDRef>ATU_00000001</audioTrackUIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1003" audioObjectName="Ambience">
          <audioPackFormatIDRef>AP_00031002</audioPackFormatIDRef>
          <audioTrackUIDRef>ATU_00000002</audioTrackUIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1004" audioObjectName="Bill">
          <audioObjectIDRef>AO_1005</audioObjectIDRef>
          <audioObjectIDRef>AO_1006</audioObjectIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1005" audioObjectName="Speech">
          <audioPackFormatIDRef>AP_00031003</audioPackFormatIDRef>
          <audioTrackUIDRef>ATU_00000003</audioTrackUIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1006" audioObjectName="Ambience">
          <audioPackFormatIDRef>AP_00031004</audioPackFormatIDRef>
          <audioTrackUIDRef>ATU_00000004</audioTrackUIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1007" audioObjectName="Intro Narrator">
          <audioPackFormatIDRef>AP_00031005</audioPackFormatIDRef>
          <audioTrackUIDRef>ATU_00000005</audioTrackUIDRef>
        </audioObject>
        <audioObject audioObjectID="AO_1008" audioObjectName="Intro Music">
          <audioPackFormatIDRef>AP_00031006</audioPackFormatIDRef>
          <audioTrackUIDRef>ATU_00000006</audioTrackUIDRef>
        </audioObject>

        <audioPackFormat audioPackFormatID="AP_00031001" audioPackFormatName="Speech" typeLabel="0003" typeDefinition="Objects">
          <audioChannelFormatIDRef>AC_00031001</audioChannelFormatIDRef>
        </audioPackFormat>
        <audioPackFormat audioPackFormatID="AP_00031002" audioPackFormatName="Ambience" typeLabel="0003" typeDefinition="Objects">
          <audioChannelFormatIDRef>AC_00031002</audioChannelFormatIDRef>
        </audioPackFormat>
        <audioPackFormat audioPackFormatID="AP_00031003" audioPackFormatName="Speech" typeLabel="0003" typeDefinition="Objects">
          <audioChannelFormatIDRef>AC_00031003</audioChannelFormatIDRef>
        </audioPackFormat>
        <audioPackFormat audioPackFormatID="AP_00031004" audioPackFormatName="Ambience" typeLabel="0003" typeDefinition="Objects">
          <audioChannelFormatIDRef>AC_00031004</audioChannelFormatIDRef>
        </audioPackFormat>
        <audioPackFormat audioPackFormatID="AP_00031005" audioPackFormatName="Intro Narrator" typeLabel="0003" typeDefinition="Objects">
          <audioChannelFormatIDRef>AC_00031005</audioChannelFormatIDRef>
        </audioPackFormat>
        <audioPackFormat audioPackFormatID="AP_00031006" audioPackFormatName="Intro Music" typeLabel="0003" typeDefinition="Objects">
          <audioChannelFormatIDRef>AC_00031006</audioChannelFormatIDRef>
        </audioPackFormat>

        <audioChannelFormat audioChannelFormatID="AC_00031001" audioChannelFormatName="Speech" typeLabel="0003" typeDefinition="Objects">
          <audioBlockFormat audioBlockFormatID="AB_00031001_00000001">
            <position coordinate="azimuth">0.000000</position>
            <position coordinate="elevation">0.000000</position>
          </audioBlockFormat>
        </audioChannelFormat>
        <audioChannelFormat audioChannelFormatID="AC_00031002" audioChannelFormatName="Ambience" typeLabel="0003" typeDefinition="Objects">
          <audioBlockFormat audioBlockFormatID="AB_00031002_00000001">
            <position coordinate="azimuth">0.000000</position>
            <position coordinate="elevation">0.000000</position>
          </audioBlockFormat>
        </audioChannelFormat>
        <audioChannelFormat audioChannelFormatID="AC_00031003" audioChannelFormatName="Speech" typeLabel="0003" typeDefinition="Objects">
          <audioBlockFormat audioBlockFormatID="AB_00031003_00000001">
            <position coordinate="azimuth">0.000000</position>
            <position coordinate="elevation">0.000000</position>
          </audioBlockFormat>
        </audioChannelFormat>
        <audioChannelFormat audioChannelFormatID="AC_00031004" audioChannelFormatName="Ambience" typeLabel="0003" typeDefinition="Objects">
          <audioBlockFormat audioBlockFormatID="AB_00031004_00000001">
            <position coordinate="azimuth">0.000000</position>
            <position coordinate="elevation">0.000000</position>
          </audioBlockFormat>
        </audioChannelFormat>
        <audioChannelFormat audioChannelFormatID="AC_00031005" audioChannelFormatName="Intro Narrator" typeLabel="0003" typeDefinition="Objects">
          <audioBlockFormat audioBlockFormatID="AB_00031005_00000001">
            <position coordinate="azimuth">0.000000</position>
            <position coordinate="elevation">0.000000</position>
          </audioBlockFormat>
        </audioChannelFormat>
        <audioChannelFormat audioChannelFormatID="AC_00031006" audioChannelFormatName="Intro Music" typeLabel="0003" typeDefinition="Objects">
          <audioBlockFormat audioBlockFormatID="AB_00031006_00000001">
            <position coordinate="azimuth">0.000000</position>
            <position coordinate="elevation">0.000000</position>
          </audioBlockFormat>
        </audioChannelFormat>

        <audioStreamFormat audioStreamFormatID="AS_00031001" audioStreamFormatName="Speech" formatLabel="0001" formatDefinition="PCM">
          <audioChannelFormatIDRef>AC_00031001</audioChannelFormatIDRef>
          <audioTrackFormatIDRef>AT_00031001_01</audioTrackFormatIDRef>
        </audioStreamFormat>
        <audioStreamFormat audioStreamFormatID="AS_00031002" audioStreamFormatName="Ambience" formatLabel="0001" formatDefinition="PCM">
          <audioChannelFormatIDRef>AC_00031002</audioChannelFormatIDRef>
          <audioTrackFormatIDRef>AT_00031002_01</audioTrackFormatIDRef>
        </audioStreamFormat>
        <audioStreamFormat audioStreamFormatID="AS_00031003" audioStreamFormatName="Speech" formatLabel="0001" formatDefinition="PCM">
          <audioChannelFormatIDRef>AC_00031003</audioChannelFormatIDRef>
          <audioTrackFormatIDRef>AT_00031003_01</audioTrackFormatIDRef>
        </audioStreamFormat>
        <audioStreamFormat audioStreamFormatID="AS_00031004" audioStreamFormatName="Ambience" formatLabel="0001" formatDefinition="PCM">
          <audioChannelFormatIDRef>AC_00031004</audioChannelFormatIDRef>
          <audioTrackFormatIDRef>AT_00031004_01</audioTrackFormatIDRef>
        </audioStreamFormat>
        <audioStreamFormat audioStreamFormatID="AS_00031005" audioStreamFormatName="Intro Narrator" formatLabel="0001" formatDefinition="PCM">
          <audioChannelFormatIDRef>AC_00031005</audioChannelFormatIDRef>
          <audioTrackFormatIDRef>AT_00031005_01</audioTrackFormatIDRef>
        </audioStreamFormat>
        <audioStreamFormat audioStreamFormatID="AS_00031006" audioStreamFormatName="Intro Music" formatLabel="0001" formatDefinition="PCM">
          <audioChannelFormatIDRef>AC_00031006</audioChannelFormatIDRef>
          <audioTrackFormatIDRef>AT_00031006_01</audioTrackFormatIDRef>
        </audioStreamFormat>

        <audioTrackFormat audioTrackFormatID="AT_00031001_01" audioTrackFormatName="Speech" formatLabel="0001" formatDefinition="PCM">
          <audioStreamFormatIDRef>AS_00031001</audioStreamFormatIDRef>
        </audioTrackFormat>
        <audioTrackFormat audioTrackFormatID="AT_00031002_01" audioTrackFormatName="Ambience" formatLabel="0001" formatDefinition="PCM">
          <audioStreamFormatIDRef>AS_00031002</audioStreamFormatIDRef>
        </audioTrackFormat>
        <audioTrackFormat audioTrackFormatID="AT_00031003_01" audioTrackFormatName="Speech" formatLabel="0001" formatDefinition="PCM">
          <audioStreamFormatIDRef>AS_00031003</audioStreamFormatIDRef>
        </audioTrackFormat>
        <audioTrackFormat audioTrackFormatID="AT_00031004_01" audioTrackFormatName="Ambience" formatLabel="0001" formatDefinition="PCM">
          <audioStreamFormatIDRef>AS_00031004</audioStreamFormatIDRef>
        </audioTrackFormat>
        <audioTrackFormat audioTrackFormatID="AT_00031005_01" audioTrackFormatName="Intro Narrator" formatLabel="0001" formatDefinition="PCM">
          <audioStreamFormatIDRef>AS_00031005</audioStreamFormatIDRef>
        </audioTrackFormat>
        <audioTrackFormat audioTrackFormatID="AT_00031006_01" audioTrackFormatName="Intro Music" formatLabel="0001" formatDefinition="PCM">
          <audioStreamFormatIDRef>AS_00031006</audioStreamFormatIDRef>
        </audioTrackFormat>

        <audioTrackUID UID="ATU_00000001">
          <audioTrackFormatIDRef>AT_00031001_01</audioTrackFormatIDRef>
          <audioPackFormatIDRef>AP_00031001</audioPackFormatIDRef>
        </audioTrackUID>
        <audioTrackUID UID="ATU_00000002">
          <audioTrackFormatIDRef>AT_00031002_01</audioTrackFormatIDRef>
          <audioPackFormatIDRef>AP_00031002</audioPackFormatIDRef>
        </audioTrackUID>
        <audioTrackUID UID="ATU_00000003">
          <audioTrackFormatIDRef>AT_00031003_01</audioTrackFormatIDRef>
          <audioPackFormatIDRef>AP_00031003</audioPackFormatIDRef>
        </audioTrackUID>
        <audioTrackUID UID="ATU_00000004">
          <audioTrackFormatIDRef>AT_00031004_01</audioTrackFormatIDRef>
          <audioPackFormatIDRef>AP_00031004</audioPackFormatIDRef>
        </audioTrackUID>
        <audioTrackUID UID="ATU_00000005">
          <audioTrackFormatIDRef>AT_00031005_01</audioTrackFormatIDRef>
          <audioPackFormatIDRef>AP_00031005</audioPackFormatIDRef>
        </audioTrackUID>
        <audioTrackUID UID="ATU_00000006">
          <audioTrackFormatIDRef>AT_00031006_01</audioTrackFormatIDRef>
          <audioPackFormatIDRef>AP_00031006</audioPackFormatIDRef>
        </audioTrackUID>
      </audioFormatExtended>
    </format>
  </coreMetadata>
</ebuCoreMain>