In-band SCTE-35 commands used for ad breaks

The Live Stream API supports two methods for inserting ad breaks into a live stream:

Creating an ad break channel event
Inserting an in-band SCTE-35 command

This page describes the in-band SCTE-35 command used for ad breaks.

Ad markers are carried on the input stream and must be compliant with the SCTE-35 specification Digital Program Insertion Cueing Message For Cable. SCTE-35 data can be carried on an MPEG-TS elementary data stream using an elementary stream type equal to 0x86. Only SRT input streams can be used to ingest inband SCTE-35 commands.

The Live Stream API parses all PIDs in the TS elementary stream.

Within the list of SCTE-35 commands, the Live Stream API supports the splice_insert command as defined in SCTE-35.

HLS manifest file

For HLS, each splice command generates a #EXT-X-CUE-OUT/#EXT-X-CUE-OUT-CONT/#EXT-X-CUE-IN marker in the manifest playlist. The splice command also generates a #EXT-OATCLS-SCTE35 entry with the SCTE-35 data encoded in base64 format, as seen in the following:

#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:44:44.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000007.m4s
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:44:48.143Z
#EXTINF:1.212833
720p60_h264_fmp4-0000000008.m4s
#EXT-OATCLS-SCTE35:/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-CUE-OUT:45.000000
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:44:49.356Z
#EXTINF:2.787167
720p60_h264_fmp4-0000000009.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=2.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:44:52.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000010.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=6.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:44:56.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000011.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=10.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:00.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000012.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=14.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:04.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000013.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=18.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:08.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000014.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=22.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:12.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000015.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=26.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:16.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000016.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=30.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:20.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000017.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=34.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:24.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000018.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=38.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:28.143Z
#EXTINF:4.000000
720p60_h264_fmp4-0000000019.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=42.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:32.143Z
#EXTINF:2.000000
720p60_h264_fmp4-0000000020.m4s
#EXT-X-CUE-OUT-CONT:ElapsedTime=44.787167,Duration=45.000000,SCTE35=/DAlAAAAAAAAAP/wFAVDE1agf+//yBysA/4APcxQAAAAAAAAXhEvvQ==
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:34.143Z
#EXTINF:0.212833
720p60_h264_fmp4-0000000021.m4s
#EXT-X-CUE-IN
#EXT-X-PROGRAM-DATE-TIME:2023-05-19T17:45:34.358Z
#EXTINF:3.784522
720p60_h264_fmp4-0000000022.m4s

DASH manifest file

For DASH, each splice command generates a new period with an <EventStream> section in the MPD file, as seen in the following:

<Period id="Dash-32.475" start="PT32.475S">
  <AdaptationSet segmentAlignment="true" maxWidth="1280" maxHeight="720">
    <Representation mimeType="video/mp4" id="720p60_h264_fmp4" codecs="avc1.4d001f" width="1280" height="720" startWithSAP="1" bandwidth="2100000">
      <SegmentTemplate timescale="1000000" initialization="720p60_h264_fmp4/720p60_h264_fmp4-initialization_segment_0000000000.m4s" media="720p60_h264_fmp4/720p60_h264_fmp4-$Number%010d$.m4s" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
    <Representation mimeType="video/mp4" id="360p30_h264_fmp4" codecs="avc1.4d001e" width="640" height="360" startWithSAP="1" bandwidth="600000">
      <SegmentTemplate timescale="1000000" initialization="360p30_h264_fmp4/360p30_h264_fmp4-initialization_segment_0000000000.m4s" media="360p30_h264_fmp4/360p30_h264_fmp4-$Number%010d$.m4s" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
  </AdaptationSet>
  <AdaptationSet segmentAlignment="true" mimeType="audio/mp4" id="1" label="441k_160_aac_fmp4">
    <Representation id="441k_160_aac_fmp4" codecs="mp4a.40.2" audioSamplingRate="44100" startWithSAP="1" bandwidth="160000">
      <SegmentTemplate timescale="1000000" initialization="441k_160_aac_fmp4/441k_160_aac_fmp4-initialization_segment_0000000000.m4s" media="441k_160_aac_fmp4/441k_160_aac_fmp4-$Number%010d$.m4s" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
  </AdaptationSet>
  <AdaptationSet segmentAlignment="true" mimeType="audio/mp4" id="2" label="48k_160_aac_fmp4">
    <Representation id="48k_160_aac_fmp4" codecs="mp4a.40.2" audioSamplingRate="48000" startWithSAP="1" bandwidth="128000">
      <SegmentTemplate timescale="1000000" initialization="48k_160_aac_fmp4/48k_160_aac_fmp4-initialization_segment_0000000000.m4s" media="48k_160_aac_fmp4/48k_160_aac_fmp4-$Number%010d$.m4s" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
  </AdaptationSet>
  <AdaptationSet contentType="text" lang="en-US" segmentAlignment="true">
    <Representation mimeType="text/vtt" id="caption_webvtt_en_webvtt" bandwidth="4698">
      <SegmentTemplate timescale="1000000" media="caption_webvtt_en_webvtt/caption_webvtt_en_webvtt-$Number%010d$.vtt" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
  </AdaptationSet>
  <AdaptationSet contentType="text" lang="es-CO" segmentAlignment="true">
    <Representation mimeType="text/vtt" id="caption_webvtt_es_webvtt" bandwidth="5450">
      <SegmentTemplate timescale="1000000" media="caption_webvtt_es_webvtt/caption_webvtt_es_webvtt-$Number%010d$.vtt" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
  </AdaptationSet>
  <AdaptationSet contentType="text" lang="zh-CN" segmentAlignment="true">
    <Representation mimeType="text/vtt" id="caption_webvtt_zh_webvtt" bandwidth="7329">
      <SegmentTemplate timescale="1000000" media="caption_webvtt_zh_webvtt/caption_webvtt_zh_webvtt-$Number%010d$.vtt" startNumber="9" presentationTimeOffset="1684475755212833">
        <SegmentTimeline>
          <S t="1684475755212833" d="2787167"/>
          <S t="1684475758000000" d="4000000" r="9"/>
          <S t="1684475798000000" d="2000000"/>
          <S t="1684475800000000" d="212833"/>
        </SegmentTimeline>
      </SegmentTemplate>
    </Representation>
  </AdaptationSet>
  <EventStream timescale="1000000" schemeIdUri="urn:scte:scte35:2013:xml">
    <Event duration="45000000" id="1684475755">
      <SpliceInfoSection xmlns="urn:scte:scte35:2013:xml">
        <SpliceInsert outOfNetworkIndicator="true" spliceImmediateFlag="true">
          <BreakDuration autoReturn="true" duration="45000000"/>
        </SpliceInsert>
      </SpliceInfoSection>
    </Event>
  </EventStream>
</Period>