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[Editorial] Refresh xref usage, drop custom script
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This refreshes the spec to leverage ReSpec cross-referencing capabilities.
See discussion in:
w3c/media-source#337 (comment)

Section 3 contained a reference to "ISO/IEC 13818-1:2012 Amd. 2". As far as I
can tell, there have been no revision of 13818-1 dated 2012, so that reference
is incorrect. The closest might be "ISO/IEC 13818-1:2013/Amd 2:2014" but this
version has been replaced by newer versions in any case. This update simply
uses `[[MPEG2TS]]`.
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@tidoust
tidoust committed Dec 5, 2023
1 parent e93b737 commit 1f45316
Showing 1 changed file with 34 additions and 75 deletions.
109 changes: 34 additions & 75 deletions index.html
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Original file line number Diff line number Diff line change
Expand Up @@ -4,13 +4,6 @@
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>MPEG-2 TS Byte Stream Format</title>
<script src="https://www.w3.org/Tools/respec/respec-w3c" class="remove"></script>
<script src="https://w3c.github.io/media-source/media-source.js" class="remove"></script>
<script class="remove">
(function() {
var mp2tContainerSpecDefinitions = {};
mediaSourceAddDefinitionInfo("mp2t-byte-stream-format", "", mp2tContainerSpecDefinitions);
})();
</script>

<script class="remove">
var respecConfig = {
Expand All @@ -33,52 +26,11 @@
{ name: "Adrian Bateman (until April 2015)", url: "", company: "Microsoft Corporation", companyURL: "https://www.microsoft.com/" },
],

mseDefGroupName: "mp2t-byte-stream-format",
mseUnusedGroupNameExcludeList: ["media-source"],
mseContributors: [
"Bob Lund",
"Alex Giladi",
"Duncan Rowden",
"Mark Vickers",
"Glenn Adams",
"Michael Thornburgh",
"David Singer",
],

// name of the WG
group: "media",

scheme: "https",

otherLinks: [{
key: 'Repository',
data: [{
value: 'We are on GitHub',
href: 'https://github.com/w3c/mse-byte-stream-format-mp2t/'
}, {
value: 'File a bug',
href: 'https://github.com/w3c/mse-byte-stream-format-mp2t/issues'
}, {
value: 'Commit history',
href: 'https://github.com/w3c/mse-byte-stream-format-mp2t/commits/main/index.html'
}]
},{
key: 'Mailing list',
data: [{
value: 'public-media-wg@w3.org',
href: 'https://lists.w3.org/Archives/Public/public-media-wg/'
}]
}],

preProcess: [ mediaSourceAddMainSpecDefinitionInfos, mediaSourcePreProcessor ],

// Empty definitions for objects declared in the document are here to
// prevent error messages from being displayed for references to these objects.
definitionMap: {},

postProcess: [ mediaSourcePostProcessor ],

xref: ["html"]
github: "w3c/mse-byte-stream-format-mp2t",
wgPublicList: "public-media-wg"
};
</script>
<!-- script to register bugs -->
Expand All @@ -89,32 +41,31 @@
<meta name="bug.component" content="Media Source Extensions">
-->
</head>
<body>
<body data-cite="html media-source">
<section id="abstract">
This specification defines a <a def-id="mse-spec"></a> [[MEDIA-SOURCE]] byte stream format specification based on MPEG-2 Transport Streams.
This specification defines a [[[MEDIA-SOURCE]]] [[MEDIA-SOURCE]] byte stream format specification based on MPEG-2 Transport Streams [[MPEG2TS]].
</section>

<section id="sotd">
<p>The working group maintains <a href="https://github.com/w3c/mse-byte-stream-format-mp2t/issues">a list of all bug reports that the editors have not yet tried to address</a>;
there may also be related open bugs in the [[MEDIA-SOURCE]] repository.</p>
there may also be related open bugs in the <a href="https://github.com/w3c/media-source">GitHub repository</a>.</p>
<p>Implementors should be aware that this specification is not stable. <strong>Implementors who are not taking part in the discussions are likely to find the specification changing out from under them in incompatible ways.</strong> Vendors interested in implementing this specification before it eventually reaches the Candidate Recommendation stage should track the <a href="https://github.com/w3c/media-source">GitHub repository</a> and take part in the discussions.</p>
</section>

<section id="introduction">
<h2>Introduction</h2>
<p>This specification defines segment formats for implementations of <a def-id="mse-spec"></a> [[!MEDIA-SOURCE]] that choose to support MPEG-2 Transport Streams
[[!MPEG2TS]].</p> It defines the MIME-type parameters used to signal codecs, and provides
the necessary format specific definitions for <a def-id="init-segments"></a>, <a def-id="media-segments"></a>, and <a def-id="random-access-points"></a> required by
the <a def-id="byte-stream-formats-section"></a> of the Media Source Extensions spec. This document also defines extra behaviors and state that only apply to this
byte stream format.</p>
<p>This specification defines segment formats for implementations of [[[MEDIA-SOURCE]]] [[!MEDIA-SOURCE]] that choose to support MPEG-2 Transport Streams [[!MPEG2TS]].</p>
<p>It defines the MIME-type parameters used to signal codecs, and provides
the necessary format specific definitions for [=initialization segments=], [=media segments=], and [=random access point=] required by
the <a data-cite="media-source#byte-stream-formats">Byte Stream Formats section</a> of the [[[MEDIA-SOURCE]]] specification. This document also defines extra behaviors and state that only apply to this byte stream format.</p>
</section>

<section id="mime-parameters">
<h2>MIME-type info</h2>
<p>The MIME-type/subtype pair of "video/MP2T", as specified in [[!RFC3551]], MUST be used for byte streams that conform
to this specification.</p>

<p>This following parameters can be used in the MIME-type passed to <a def-id="isTypeSupported"></a> or <a def-id="addSourceBuffer"></a>.</p>
<p>This following parameter can be used in the MIME-type passed to {{MediaSource/isTypeSupported()}} or {{MediaSource/addSourceBuffer()}}.</p>
<dl>
<dt>codecs</dt>
<dd>
Expand All @@ -126,9 +77,9 @@ <h2>MIME-type info</h2>

<section id="mpeg2ts-general">
<h4>General Transport Stream Requirements</h4>
<p>MPEG-2 TS media and initialization segments MUST conform to the MPEG-2 TS Adaptive Profile (ISO/IEC 13818-1:2012 Amd. 2).</p>
<p>MPEG-2 TS [=media segments=] and [=initialization segments=] MUST conform to the MPEG-2 TS Adaptive Profile [[MPEG2TS]].</p>

<p>The user agent MUST run the <a def-id="append-decode-error-algorithm"></a> if any of the following conditions are met:</p>
<p>The user agent MUST run the [=append error=] algorithm if any of the following conditions are met:</p>
<ol>
<li>Segments do not contain complete MPEG-2 TS packets.</li>
<li>Segments do not contain complete PES packets and sections.</li>
Expand All @@ -138,34 +89,34 @@ <h4>General Transport Stream Requirements</h4>
</section>
<section id="mpeg2ts-init-segments">
<h4>Initialization Segments</h4>
<p>An MPEG-2 TS initialization segment consists of a single PAT and a single PMT.</p>
<p>The user agent MUST run the <a def-id="append-decode-error-algorithm"></a> if any of the following conditions are met:</p>
<p>An MPEG-2 TS [=initialization segment=] consists of a single PAT and a single PMT.</p>
<p>The user agent MUST run the [=append error=] algorithm if any of the following conditions are met:</p>
<ol>
<li>A PAT is not present in the <a def-id="init-segment"></a></li>
<li>A PMT is not present in the <a def-id="init-segment"></a></li>
<li>A PAT is not present in the [=initialization segment=]</li>
<li>A PMT is not present in the [=initialization segment=]</li>
</ol>

<p>The user agent MUST accept and ignore other SI, such as CAT, that are invariant for all subsequent media segments.</p>
<p>The user agent MUST source attribute values for id, kind, label and language for {{AudioTrack}}, {{VideoTrack}} and
<p>The user agent MUST accept and ignore other SI, such as CAT, that are invariant for all subsequent [=media segments=].</p>
<p>The user agent MUST source attribute values for `id`, `kind`, `label` and `language` for {{AudioTrack}}, {{VideoTrack}} and
{{TextTrack}} objects as described for MPEG-2 Transport Streams in the in-band tracks spec [[INBANDTRACKS]].</p>
</section>

<section id="mpeg2ts-media-segments">
<h4>Media Segments</h4>

<p>The user agent MUST run the <a def-id="append-decode-error-algorithm"></a> if any of the following conditions are met:</p>
<p>The user agent MUST run the [=append error=] algorithm if any of the following conditions are met:</p>
<ol>
<li>A media segment relies on initialization information in another media segment.</li>
<li>A [=media segment=] relies on initialization information in another [=media segment=].</li>
<li>At least one PES packet does not have a PTS timestamp.</li>
<li>PCR is not present in the Segment prior to the first byte of a TS packet payload containing media data.</li>
</ol>

The user agent will accept and ignore PSI that is identical to the information in the last initialization segment which may appear repeatedly throughout the segment.
The user agent will accept and ignore PSI that is identical to the information in the last [=initialization segment=] which may appear repeatedly throughout the segment.
</section>

<section id="mpeg2ts-random-access-points">
<h4>Random Access Points</h4>
<p>A random access point as defined in this specification corresponds to Elementary Stream Random Access Point as defined in
<p>A [=random access point=] as defined in this specification corresponds to Elementary Stream Random Access Point as defined in
[[!MPEG2TS]].</p>
</section>
<section id="mpeg2ts-discontinuities">
Expand All @@ -174,7 +125,7 @@ <h4>Timestamp Rollover &amp; Discontinuities</h4>
variable, <dfn>MPEG2TS_timestampOffset</dfn>, to keep track of the offset that needs to be applied to timestamps
that have rolled over or are part of a discontinuity. <a>MPEG2TS_timestampOffset</a> is initially set to 0 when the <a class="externalDFN">SourceBuffer</a> is
created. This offset MUST be applied to the timestamps as part of the conversion process from MPEG-2 TS packets
into <a def-id="coded-frames"></a> for the <a def-id="coded-frame-processing-algorithm"></a>. This results in the coded frame timestamps
into [=coded frames=] for the [=coded frame processing=] algorithm. This results in the coded frame timestamps
for a packet being computed by the following equations:</p>
<pre>
Coded Frame Presentation Timestamp = (MPEG-2 TS presentation timestamp) + <var>MPEG2TS_timestampOffset</var>
Expand All @@ -185,16 +136,24 @@ <h4>Timestamp Rollover &amp; Discontinuities</h4>
<li>Each time a timestamp rollover is detected, 2^33 MUST be added to <a>MPEG2TS_timestampOffset</a>.</li>
<li>When a discontinuity is detected, <a>MPEG2TS_timestampOffset</a> MUST be adjusted to make the timestamps after the discontinuity appear
to come immediately after the timestamps before the discontinuity.</li>
<li>When <a def-id="abort"></a> is called, <a>MPEG2TS_timestampOffset</a> MUST be set to 0.</li>
<li>When <a def-id="timestampOffset"></a> is successfully set, <a>MPEG2TS_timestampOffset</a> MUST be set to 0.</li>
<li>When {{SourceBuffer/abort()}} is called, <a>MPEG2TS_timestampOffset</a> MUST be set to 0.</li>
<li>When {{SourceBuffer/timestampOffset}} is successfully set, <a>MPEG2TS_timestampOffset</a> MUST be set to 0.</li>
</ul>
</section>

<section id="conformance"></section>

<section id="acknowledgements">
<h2>Acknowledgments</h2>
The editors would like to thank <a def-id="contributors"></a> for their contributions to this specification.
The editors would like to thank

Alex Giladi,
Bob Lund,
David Singer,
Duncan Rowden,
Glenn Adams,
Mark Vickers,
and Michael Thornburgh for their contributions to this specification.
</section>
</body>
</html>

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