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<bugzilla version="5.0.4"
          urlbase="https://www.w3.org/Bugs/Public/"
          
          maintainer="sysbot+bugzilla@w3.org"
>

    <bug>
          <bug_id>28710</bug_id>
          
          <creation_ts>2015-05-28 07:49:53 +0000</creation_ts>
          <short_desc>[MSE] Ambiguous behavior with Coded Frame Processing algorithm</short_desc>
          <delta_ts>2015-10-13 23:10:05 +0000</delta_ts>
          <reporter_accessible>1</reporter_accessible>
          <cclist_accessible>1</cclist_accessible>
          <classification_id>1</classification_id>
          <classification>Unclassified</classification>
          <product>HTML WG</product>
          <component>Media Source Extensions</component>
          <version>unspecified</version>
          <rep_platform>PC</rep_platform>
          <op_sys>All</op_sys>
          <bug_status>RESOLVED</bug_status>
          <resolution>MOVED</resolution>
          
          
          <bug_file_loc></bug_file_loc>
          <status_whiteboard></status_whiteboard>
          <keywords></keywords>
          <priority>P2</priority>
          <bug_severity>normal</bug_severity>
          <target_milestone>---</target_milestone>
          
          
          <everconfirmed>1</everconfirmed>
          <reporter name="Jean-Yves Avenard">jyavenard</reporter>
          <assigned_to name="Matt Wolenetz">wolenetz</assigned_to>
          <cc>jdsmith</cc>
    
    <cc>mike</cc>
    
    <cc>public-html-media</cc>
          
          <qa_contact name="HTML WG Bugzilla archive list">public-html-bugzilla</qa_contact>

      

      

      

          <comment_sort_order>oldest_to_newest</comment_sort_order>  
          <long_desc isprivate="0" >
    <commentid>120556</commentid>
    <comment_count>0</comment_count>
    <who name="Jean-Yves Avenard">jyavenard</who>
    <bug_when>2015-05-28 07:49:53 +0000</bug_when>
    <thetext>In the Coded Frame Processing algorithm:
http://w3c.github.io/media-source/index.html#sourcebuffer-coded-frame-processing

In Step 13. &quot;If track buffer contains video coded frames:&quot;

you find:
&quot;If the presentation timestamp is less than the remove window timestamp, then remove overlapped frame and any coded frames that depend on it from track buffer.
&quot;

This imply that we are to have detailed information about decoding dependencies available. We can&apos;t remove the frames depending on the removed frames otherwise.

However, Step 15. describes how to remove dependent frames for frames removed in the previous step (step 14.) should we have &quot;detailed information about decoding dependencies is available&quot;.
If such information isn&apos;t available, then we are to &quot;Remove all coded frames between the coded frames removed in the previous step and the next random access point after those removed frames. &quot;


I suggest that Step 13 removes the mention of &quot; and any coded frames that depend on it&quot;

and have Step 15 have instead:
&quot;Remove decoding dependencies of the coded frames removed in the previous two steps: &quot;

This would mean we have a common code path for the removal of dependent frames.

As a side note, Step 15 note: &quot;Removing all coded frames until the next random access point is a conservative estimate of the decoding dependencies since it assumes all frames between the removed frames and the next random access point depended on the frames that were removed. &quot;

doesn&apos;t appear to cater for B-frames found prior the &quot;coded frames removed&quot; and dependent on the frames removed. This could leave frames that can&apos;t be decoded in the track buffer.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>123698</commentid>
    <comment_count>1</comment_count>
    <who name="Matt Wolenetz">wolenetz</who>
    <bug_when>2015-10-13 23:10:05 +0000</bug_when>
    <thetext>This bug has been migrated to the GitHub issue tracker. Please follow/update progress using the GitHub issue:
https://github.com/w3c/media-source/issues/25</thetext>
  </long_desc>
      
      

    </bug>

</bugzilla>