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mpeg-audio-byte-stream-format-respec.html
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<!DOCTYPE html SYSTEM "about:legacy-compat">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>MPEG Audio Byte Stream Format</title>
<script src="https://www.w3.org/Tools/respec/respec-w3c-common" class="remove"></script>
<!--<script src="respec-w3c-common.js" class="remove"></script>-->
<script src="media-source.js" class="remove"></script>
<script class="remove">
(function() {
var mpegContainerSpecDefinitions = {
'iso-11172-3': { fragment: 'http://www.iso.org/iso/catalogue_detail.htm?csnumber=22412', link_text: 'ISO/IEC 11172-3:1993', },
'iso-13818-3': { fragment: 'http://www.iso.org/iso/catalogue_detail.htm?csnumber=26797', link_text: 'ISO/IEC 13818-3:1998', },
'iso-14496-3': { fragment: 'http://www.iso.org/iso/catalogue_detail.htm?csnumber=53943', link_text: 'ISO/IEC 14496-3:2009', },
'id3v1': { fragment: 'http://id3.org/ID3v1', link_text: 'ID3v1', },
'id3v2': { fragment: 'http://id3.org/id3v2.3.0', link_text: 'ID3v2', },
'icecast-headers': { fragment: '#icecast-header', link_text: 'Icecast headers', },
'mpeg-mime-type': { fragment: '#mime-types', link_text: 'MIME-type', },
'mpeg-mime-types': { fragment: '#mime-types', link_text: 'MIME-types', },
'mpeg-audio-frame': { fragment: '#mpeg-audio-frame', link_text: 'MPEG Audio Frame', },
'mpeg-audio-frames': { fragment: '#mpeg-audio-frame', link_text: 'MPEG Audio Frames', },
'mpeg-audio-metadata-frames': { fragment: '#mpeg-metadata', link_text: 'Metadata Frames', },
};
mediaSourceAddDefinitionInfo("mpeg-byte-stream-format", "", mpegContainerSpecDefinitions);
})();
</script>
<script class="remove">
var respecConfig = {
// specification status (e.g. WD, LCWD, NOTE, etc.). If in doubt use ED.
specStatus: "ED",
// the specification's short name, as in http://www.w3.org/TR/short-name/
shortName: "mse-byte-stream-format-mpeg-audio",
// if there a publicly available Editor's Draft, this is the link
edDraftURI: "https://w3c.github.io/media-source/mpeg-audio-byte-stream-format.html",
// if this is a LCWD, uncomment and set the end of its review period
// lcEnd: "2009-08-05",
//publishDate: "2015-03-09",
prevVersion: "https://www.w3.org/2013/12/byte-stream-format-registry/mpeg-audio-byte-stream-format.html",
// editors, add as many as you like
// only "name" is required
editors: [
{ name: "Dale Curtis", url: "", company: "Google Inc.", companyURL: "http://www.google.com/" },
{ name: "Matthew Wolenetz", url: "", company: "Google Inc.", companyURL: "http://www.google.com/" },
{ name: "Aaron Colwell (until April 2015)", url: "", company: "Google Inc.", companyURL: "http://www.google.com/" },
],
mseDefGroupName: "mpeg-byte-stream-format",
mseUnusedGroupNameExcludeList: ["media-source"],
mseContributors: [
],
// name of the WG
wg: "HTML Media Extensions Working Group",
// URI of the public WG page
wgURI: "https://www.w3.org/html/wg/",
// name (without the @w3c.org) of the public mailing to which comments are due
wgPublicList: "public-html-media",
// URI of the patent status for this WG, for Rec-track documents
// !!!! IMPORTANT !!!!
// This is important for Rec-track documents, do not copy a patent URI from a random
// document unless you know what you're doing. If in doubt ask your friendly neighbourhood
// Team Contact.
wgPatentURI: "https://www.w3.org/2004/01/pp-impl/40318/status",
noIDLIn: true,
scheme: "https",
otherLinks: [{
key: 'Repository',
data: [{
value: 'We are on GitHub',
href: 'https://github.com/w3c/media-source/'
}, {
value: 'File a bug',
href: 'https://github.com/w3c/media-source/issues'
}, {
value: 'Commit history',
href: 'https://github.com/w3c/media-source/commits/gh-pages/mpeg-audio-byte-stream-format-respec.html'
}]
},{
key: 'Mailing list',
data: [{
value: '[email protected]',
href: 'https://lists.w3.org/Archives/Public/public-html-media/'
}]
}],
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 ]
};
</script>
<!-- script to register bugs -->
<!-- Disabled unless/until it supports GitHub issues.
<script src="https://w3c.github.io/webcomponents/assets/scripts/bug-assist.js"></script>
<meta name="bug.short_desc" content="[MSE] ">
<meta name="bug.product" content="HTML WG">
<meta name="bug.component" content="Media Source Extensions">
-->
<link rel="stylesheet" href="mse.css">
</head>
<body>
<section id="abstract">
This specification defines a <a def-id="mse-spec"></a> [[!MEDIA-SOURCE]] byte stream format specification based on MPEG audio streams.
</section>
<section id="sotd">
<p>The working group maintains <a href="https://github.com/w3c/media-source/issues">a list of all bug reports that the editors have not yet tried to address</a>; there may also be open bugs in the <a href="http://w3.org/brief/Mjcw">previous bug tracker</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 join the mailing list mentioned below and take part in the discussions.</p>
</section>
<section id="introduction">
<h2>Introduction</h2>
<p>This specification defines segment formats for implementations that choose to support MPEG audio streams specified in <a def-id="iso-11172-3"></a>, <a def-id="iso-13818-3"></a>, and <a def-id="iso-14496-3"></a>.</p>
<p>It defines the <a def-id="mpeg-mime-types"></a> 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. It also defines extra behaviors and state that only apply to this byte stream format.</p>
</section>
<section id="mime-types">
<h2>MIME-types</h2>
<p>This section specifies the MIME-types that may be passed to <a def-id="isTypeSupported"></a> or <a def-id="addSourceBuffer"></a> for byte streams that conform to this specification.</p>
<ul>
<li>"audio/aac" for sequences of ADTS frames, as specified in <a def-id="iso-14496-3"></a>.</li>
<li>"audio/mpeg" for MPEG-1/2/2.5 Layer I/II/III streams, as specified in <a href="http://tools.ietf.org/html/rfc3003">RFC 3003</a> [[!RFC3003]].</li>
</ul>
<p>The "codecs" MIME-type parameter MUST NOT be used with these MIME-types.</p>
</section>
<section id="mpeg-audio-frames">
<h2>MPEG Audio Frames</h2>
<p>The format of an <dfn id="mpeg-audio-frame">MPEG Audio Frame</dfn> depends on the <a def-id="mpeg-mime-type"></a> used.</p>
<ul>
<li>If the "audio/aac" MIME-type is used, an MPEG Audio Frame is a sequence of bytes that conform to the adts_frame() syntax specified in Table 1.A.5 of <a def-id="iso-14496-3"></a>.</li>
<li>If the "audio/mpeg" MIME-type is used, an MPEG Audio Frame is a sequence of bytes that conform to the frame() syntax element specified in Section 2.4.1.2 of <a def-id="iso-11172-3"></a> or the corresponding definition in <a def-id="iso-13818-3"></a>.</li>
</ul>
</section>
<section id="mpeg-metadata">
<h4>Metadata Frames</h4>
<p>Since <a def-id="id3v1"></a>, <a def-id="id3v2"></a> metadata frames, and <a def-id="icecast-headers"></a> are common in existing MPEG audio streams, implementations SHOULD gracefully handle such frames. Zero or more of these metadata frames are allowed to occur before, after, or between <a def-id="mpeg-audio-frames"></a>. Minimal implementations MUST accept, consume, and ignore these frames. More advanced implementations MAY choose to expose the metadata information via an inband <a def-id="text-track"></a> or some other mechanism.</p>
<section id="icecast">
<h3>Icecast headers</h3>
<p>There is no normative spec for <a href="http://en.wikipedia.org/wiki/Icecast">Icecast</a>/<a href="http://en.wikipedia.org/wiki/SHOUTcast">SHOUTcast</a> headers, just <a href="http://forums.radiotoolbox.com/viewtopic.php?t=74">examples</a>. For the purpose of this specification, an <dfn id="icecast-header">Icecast header</dfn> is defined as beginning with the 4 character sequence "ICY "(U+0049 I, U+0043 C, U+0059 Y, U+0020 SPACE) and ending with a pair of carriage-return line-feed sequences (U+000D CARRIAGE RETURN, U+000A LINE FEED, U+000D CARRIAGE RETURN, U+000A LINE FEED).</p>
<p class="note">Icecast headers are allowed in the byte streams because some Icecast and SHOUTcast
servers return a status line that looks like "ICY OK 200" instead of a standard HTTP status line.
User-agent network stacks typically interpret this as an HTTP 0.9 response and include the
header in the response body. Allowing these headers to appear provides a simple way to
interoperate with these servers.</p>
</section>
</section>
<section id="mpeg-segments">
<h4>Segment Definitions</h4>
<p>The MPEG audio byte stream is a combination of one or more <a def-id="mpeg-audio-frames"></a> and zero or more <a def-id="mpeg-audio-metadata-frames"></a>.</p>
<ul>
<li>Every <a def-id="mpeg-audio-frame"></a> is a <a def-id="random-access-point"></a>.</li>
<li>Every <a def-id="mpeg-audio-frame"></a> header is an <a def-id="init-segment"></a>.</li>
<li>The coded audio in each <a def-id="mpeg-audio-frame"></a> is a <a def-id="media-segment"></a>.</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.
</section> -->
</body>
</html>