Skipping milliseconds in a combined MPD file

[smriti0302]

I have multiple mpd files, which I've merged into one. So, the file has different periods of varying durations. Each period has its audio and video segments, and the segment durations vary across periods.
When i play the combined file on the DASH player, I have noticed that it is not playing the last few milliseconds of the video (here, period).
I'm not sure why this is happening. My use case requires the videos(periods) to be seamless and complete(no time should be skipped over).
Any advice on how this can be done?
This is what the combined mpd looks like :

<?xml version="1.0" ?>
<MPD mediaPresentationDuration="PT24.000S" minBufferTime="PT5.00S" profiles="urn:mpeg:dash:profile:isoff-live:2011" type="static" xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:cenc="urn:mpeg:cenc:2013" xmlns:mspr="urn:microsoft:playready">
  <!-- Created with Bento4 mp4-dash.py, VERSION=2.0.0-641 -->
  <Period duration="PT8.000S" id="feet_apart_arms_down_ai_and_non_ai_drm">
    <!-- Video -->
    <AdaptationSet maxHeight="1080" maxWidth="1920" mimeType="video/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="(kid here)" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:(uuid here)" value="2.0">
        <mspr:pro>(some text here)</mspr:pro>
        <cenc:pssh>(some text here)</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="5000" initialization="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/init.mp4" media="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation bandwidth="10415584" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/1" scanType="progressive" width="1920"/>
      <Representation bandwidth="4142673" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/2" scanType="progressive" width="1920"/>
      <Representation bandwidth="1589566" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/3" scanType="progressive" width="1920"/>
    </AdaptationSet>
    <!-- Audio -->
    <AdaptationSet lang="en" mimeType="audio/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="(kid here)" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:(uuid here)" value="2.0">
        <mspr:pro>(some text here)</mspr:pro>
        <cenc:pssh>(some text here)</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="5000" initialization="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/init.mp4" media="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation audioSamplingRate="48000" bandwidth="139455" codecs="mp4a.40.2" id="audio/en/mp4a.40.2">
        <AudioChannelConfiguration schemeIdUri="urn:mpeg:mpegB:cicp:ChannelConfiguration" value="2"/>
      </Representation>
    </AdaptationSet>
  </Period>
    
  <!--feet_apart_arms_down_ai_and_non_ai_drm--> 
  <Period duration="PT8.000S" id="feet_apart_arms_down_ai_and_non_ai_drm">
    <!-- Video -->
    <AdaptationSet maxHeight="1080" maxWidth="1920" mimeType="video/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="(kid here)" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:(uuid here)" value="2.0">
        <mspr:pro>(some text here)</mspr:pro>
        <cenc:pssh>(some text here)</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="5000" initialization="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/init.mp4" media="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation bandwidth="10415584" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/1" scanType="progressive" width="1920"/>
      <Representation bandwidth="4142673" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/2" scanType="progressive" width="1920"/>
      <Representation bandwidth="1589566" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/3" scanType="progressive" width="1920"/>
    </AdaptationSet>
    <!-- Audio -->
    <AdaptationSet lang="en" mimeType="audio/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="(kid here)" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:(uuid here)" value="2.0">
        <mspr:pro>(some text here)</mspr:pro>
        <cenc:pssh>(some text here)</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="5000" initialization="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/init.mp4" media="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation audioSamplingRate="48000" bandwidth="139455" codecs="mp4a.40.2" id="audio/en/mp4a.40.2">
        <AudioChannelConfiguration schemeIdUri="urn:mpeg:mpegB:cicp:ChannelConfiguration" value="2"/>
      </Representation>
    </AdaptationSet>
  </Period> 
        
  <!--feet_apart_arms_down_ai_and_non_ai_drm--> 
  <Period duration="PT8.000S" id="feet_apart_arms_down_ai_and_non_ai_drm">
    <!-- Video -->
    <AdaptationSet maxHeight="1080" maxWidth="1920" mimeType="video/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="(kid here)" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:(uuid here)" value="2.0">
        <mspr:pro>(some text here)</mspr:pro>
        <cenc:pssh>(some text here)</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="5000" initialization="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/init.mp4" media="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation bandwidth="10415584" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/1" scanType="progressive" width="1920"/>
      <Representation bandwidth="4142673" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/2" scanType="progressive" width="1920"/>
      <Representation bandwidth="1589566" codecs="avc1.64002A" frameRate="50" height="1080" id="video/avc1/3" scanType="progressive" width="1920"/>
    </AdaptationSet>
    <!-- Audio -->
    <AdaptationSet lang="en" mimeType="audio/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="(kid here)" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:(uuid here)" value="2.0">
        <mspr:pro>(some text here)</mspr:pro>
        <cenc:pssh>(some text here)</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="5000" initialization="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/init.mp4" media="feet_apart_arms_down_ai_and_non_ai_drm/$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation audioSamplingRate="48000" bandwidth="139455" codecs="mp4a.40.2" id="audio/en/mp4a.40.2">
        <AudioChannelConfiguration schemeIdUri="urn:mpeg:mpegB:cicp:ChannelConfiguration" value="2"/>
      </Representation>
    </AdaptationSet>
  </Period> 
</MPD>

[dsilhavy]

It is hard to tell without seeing the media segments and checking the playback. Can you host the content on a CDN/webserver and provide the license server url and tokens?

Some initial thoughts:

• Check the log output of dash.js for the "gap" keyword, your segments might overlap the period boundaries. Some related information: https://websites.fraunhofer.de/video-dev/common-pitfalls-in-mpeg-dash-streaming/
• Ideally, your content is conditioned in a way that you set the period boundaries at segment boundaries. It looks like you are trying to play media segments only partially
• The start times of media segments are relative to the start of their period.
• You can read a bit more about multiperiod related appendWindows here: https://websites.fraunhofer.de/video-dev/mse-a-story-of-append-windows-presentation-timestamps-and-video-buffers/

[smriti0302]

Sure, I'll be happy to share that with you. Can you please share your email ID so I can send the information?

[dsilhavy]

Please send to daniel.silhavy(at)fokus.fraunhofer.de