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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!--
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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Media Access Events</title>
<link rel="stylesheet" href="respec-w3c.css" type="text/css" />
<link rel="stylesheet" href="http://www.w3.org/StyleSheets/TR/W3C-WD" type="text/css" />
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<body><div class="head"><p><a href="http://www.w3.org/"><img src="http://www.w3.org/Icons/w3c_home" width="72" height="48" alt="W3C" /></a></p><h1 class="head">Media Access Events</h1><h2 id="pagesubtitle">W3C Working Draft <em>13 October 2006</em></h2>
<dl><dt>This version:</dt>
<dd><a href="http://www.w3.org/TR/2006/WD-MediaAccessEvents-20061013/">http://www.w3.org/TR/2006/WD-MediaAccessEvents-20061013/</a></dd>
<dt>Latest version:</dt>
<dd><a href="http://www.w3.org/TR/MediaAccessEvents/">http://www.w3.org/TR/MediaAccessEvents/</a></dd>
<dt>Editors:</dt>
<dd><span class="person">Ola Andersson (<a href="http://www.ikivo.com/">Ikivo</a>) <<a href="mailto:ola.andersson@ikivo.com">ola.andersson@ikivo.com</a>></span></dd><dd><span class="person">Jean-Claude Dufourd (<a href="http://www.streamezzo.com/">Streamezzo</a>) <<a href="mailto:jean-claude.dufourd@streamezzo.com">jean-claude.dufourd@streamezzo.com</a>></span></dd><dd><span class="person">Roland Lundblad (<a href="http://www.ikivo.com/">Ikivo</a>) <<a href="mailto:roland.lundblad@ikivo.com">roland.lundblad@ikivo.com</a>></span></dd></dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> ©2006
<a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>®</sup>
(<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>,
<a href="http://www.ercim.org/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>,
<a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C
<a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
<a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and
<a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.
</p></div><hr />
<h2 id="specabstract">Abstract</h2><div class="section">
<p>
This specification defines a set of DOM 3 Events [<cite><a href="#DOM3EV" class="bibref">DOM3EV</a></cite>] compatible events and DOM APIs related to
media access. The defined events and APIs enables detailed monitoring of media stream buffering and initialization.
They are designed to be easily combined with the SVG Tiny 1.2 [<cite><a href="#SVGT12" class="bibref">SVGT12</a></cite>] uDOM but can equally well be combined
with other, larger DOM APIs.
</p>
</div>
<div class="section"><h2 id="sotd">Status of this Document</h2>
<p>
<em>This section describes the status of this document at the time of its publication.
Other documents may supersede this document. A list of current <acronym title="World Wide Web Consortium">W3C</acronym> publications and the
latest revision of this technical report can be found in the
<a href="http://www.w3.org/TR/"><acronym title="World Wide Web Consortium">W3C</acronym>
technical reports index</a> at http://www.w3.org/TR/.</em>
</p>
<p>This is a First Public Working Draft of "Media Access Events".</p>
<p class="custom">This specification has been released for public feedback regarding the
overall design and functionality; in particular, whether it meets the
needs of OMA, ISO SC 29, SVG, and SMIL for event-driven access to streaming
media. It should not be implemented at this stage.</p>
<p>
This document was developed by the <a href="http://www.w3.org/Graphics/SVG/">SVG
<acronym title="Working Group">WG</acronym></a> as part of the <acronym title="World Wide Web Consortium">W3C</acronym>
<a href="http://www.w3.org/Graphics/Activity">Graphics Activity</a>.
The Working Group expects to advance this Working Draft to Recommendation Status.
</p>
<p>
Web content and browser developers are encouraged to review this draft.
Please send comments to <a href="mailto:www-svg@w3.org">www-svg@w3.org</a>,
the public email list for issues related to SVG.
<a href="http://lists.w3.org/Archives/Public/www-svg/">Archives</a> of the
list are available.
</p>
<p>
Publication as a Working Draft does not imply endorsement by the <acronym title="World Wide Web Consortium">W3C</acronym> Membership.
This is a draft document and may be updated, replaced or obsoleted by other
documents at any time. It is inappropriate to cite this document as other than
work in progress.
</p>
<p>This document was produced by a group operating under the
<a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5
February 2004 <acronym title="World Wide Web Consortium">W3C</acronym> Patent Policy</a>.
<acronym title="World Wide Web Consortium">W3C</acronym> maintains a <a rel="disclosure" href="http://www.w3.org/2004/01/pp-impl/19480/status">public list of any
patent disclosures</a> made in connection with the
deliverables of the group; that page also includes
instructions for disclosing a patent.
An individual who has actual knowledge of a patent which the
individual believes contains <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential Claim(s)</a> must disclose the
information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the <acronym title="World Wide Web Consortium">W3C</acronym> Patent Policy</a>.</p>
</div>
<div class="section"><h2 id="contents">Table of Contents</h2>
<ul class="toc"><li><a href="#introduction">1. Introduction</a></li><li><a href="#definitions">2. Definitions</a></li><li><a href="#stateChart">3. State chart</a></li><li><a href="#MediaAccessEvent-if">4. The MediaAccessEvent interface</a></li><li><a href="#MediaStreamInfo-if">5. The MediaStreamInfo interface</a></li><li><a href="#MediaStreamInfoList-if">6. The MediaStreamInfoList interface</a></li><li><a href="#conform">7. Conformance</a></li><li><a href="#example">8. Examples of usage</a></li><li><ul class="toc"><li><a href="#example-1">8.1. Simple state information display</a></li><li><a href="#example-2">8.2. Buffering progress bar</a></li><li><a href="#example-3">8.3. Stream info box</a></li></ul></li><li><a href="#ack">9. Acknowledgements</a></li></ul><ul class="toc"><li><a href="#bibref">A. References</a></li></ul>
</div>
<div class="section"><h2 id="introduction">1. Introduction</h2><p><strong>This section is informative.</strong></p>
<p>
Streamable media, such as audio and video, is streamed over the network and is processed on the client as it
arrives.
This leads to different behaviour compared to downloaded media. The client normally holds a buffer where it
stores part
of the media prior to processing it. The state of this buffer affects the client. For example, if the buffer
fills too slowly
in relation to client processing the client will have to stall processing while it waits for the buffer to
fill. It is
often of interest to monitor the state of the buffer and client, and the purpose of correlating
media access
events introduced in this specification is to facilitate such monitoring.
Initialising a
<a class="term" href="#dfn-session">session</a>
containing one or several media streams often takes a considerable
amount of time.
The author may wish to give the user some feedback that this setup is in progress and, when setup is done,
present information of the available media streams.
</p>
</div>
<div class="section"><h2 id="definitions">2. Definitions</h2>
<p>The Media Access Events
<dfn id="dfn-namespace">namespace</dfn>
is
<strong>http://www.w3.org/ns/media-access-event#</strong>
.
</p>
<p>The examples in this specification use a namespace prefix of
<strong>me</strong>
to denote the Media Access Events
<a class="term" href="#dfn-namespace">namespace</a>
.
</p>
<p>A
<dfn id="dfn-session">session</dfn>
is a set of synchronized streams rendered by a single media element.
</p>
</div>
<div class="section"><h2 id="stateChart">3. State chart</h2><p><strong>This section is informative.</strong></p>
<p>The following state chart illustrates the flow of events generated when streaming a media resource.
Even if multiple streams are rendered by a single media element within one
<a class="term" href="#dfn-session">session</a>
, only one event is fired
at each stage.
</p>
<img src="images/stateChart.png" alt="State chart" />
<p>This chart can be explained as follows:</p>
<ul>
<li>The UA goes into the
<strong>Setting Session</strong>
state, firing a
'<a href="#event-BeginSessionSetup" class="event-name">BeginSessionSetup</a>'
event. If a connection request needs to be sent to the server, it is sent during this phase.
</li>
<li>The UA goes into the
<strong>Session Setup</strong>
state, firing a
'<a href="#event-EndSessionSetup" class="event-name">EndSessionSetup</a>'
event, upon completion of the
<a class="term" href="#dfn-session">session</a>
set up on the terminal. If the
<a class="term" href="#dfn-session">session</a>
setup cannot be completed, the UA goes into the
<strong>Stopped</strong>
state and fires a
'<a href="#event-Error" class="event-name">Error</a>'
event. If a connection to a server was attempted, it was successful.
</li>
<li>The UA goes into the
<strong>Reception</strong>
state, firing a
'<a href="#event-DataRequest" class="event-name">DataRequest</a>'
event, while sending a request for data to the server. If the data request cannot be sent, the UA goes
into the
<strong>Stopped</strong>
state and fires a
'<a href="#event-Error" class="event-name">Error</a>'
event. While in this state, the UA may fire
'<a href="#event-DataReceptionProgress" class="event-name">DataReceptionProgress</a>'
events.
</li>
<li>The UA goes into the
<strong>Reception and Playing</strong>
state, firing a
'<a href="#event-Playable" class="event-name">Playable</a>'
event, when enough data has been received to start playing. If the operation is unsuccessful,
the UA goes into the
<strong>Stopped</strong>
state and fires a
'<a href="#event-Error" class="event-name">Error</a>'
event. While in this state, the UA may fire
'<a href="#event-DataReceptionProgress" class="event-name">DataReceptionProgress</a>'
events.
</li>
<li>From the
<strong>Reception and Playing</strong>
state, the UA may either go into the
<strong>Playing</strong>
state, firing a
'<a href="#event-EndOfDataReception" class="event-name">EndOfDataReception</a>'
event, when the end of the data has arrived, or back into the
<strong>Reception</strong>
state, firing a
'<a href="#event-NotPlayable" class="event-name">NotPlayable</a>'
event if there is not enough data available to continue playing. If the operation is unsuccessful, the
UA
goes into the
<strong>Stopped</strong>
state and fires a
'<a href="#event-Error" class="event-name">Error</a>'
event.
</li>
<li>From the
<strong>Playing</strong>
state, the UA goes into the
<strong>Stopped</strong>
state, firing a
'<a href="#event-Stop" class="event-name">Stop</a>'
event, at the end of the playing of available data. If the operation is unsuccessful, the UA
goes into the
<strong>Stopped</strong>
state and fires a
'<a href="#event-Error" class="event-name">Error</a>'
event.
</li>
</ul>
</div>
<div class="section"><h2 id="MediaAccessEvent-if">4. The MediaAccessEvent interface</h2>
<p>
The Media Access Event module contains basic event types associated with media access. This interface
inherits from the
<a href="http://www.w3.org/TR/SVGMobile12/svgudom.html#events__Event">Event</a>
interface in the SVG uDOM [<cite><a href="#SVGT12" class="bibref">SVGT12</a></cite>].
</p>
<div class="boxed"><p><span class="idlTitle">The MediaAccessEvent interface</span></p><pre class="schema" title="The MediaAccessEvent interface">interface <a href="#idl-if-MediaAccessEvent">MediaAccessEvent</a> : events::Event {
// MediaAccessEvent
const unsigned short <a href="#idl-defs-MediaAccessEvent-STATUS_OK">STATUS_OK</a> = 0;
const unsigned short <a href="#idl-defs-MediaAccessEvent-STATUS_ERROR_ON_SETUP">STATUS_ERROR_ON_SETUP</a> = 1;
const unsigned short <a href="#idl-defs-MediaAccessEvent-STATUS_ERROR_UNSUPPORTED_MEDIA">STATUS_ERROR_UNSUPPORTED_MEDIA</a> = 2;
const unsigned short <a href="#idl-defs-MediaAccessEvent-STATUS_ERROR_CORRUPT_STREAM">STATUS_ERROR_CORRUPT_STREAM</a> = 3;
readonly attribute boolean <a href="#dfn-bufferlevelvalid">bufferLevelValid</a>;
readonly attribute unsigned long <a href="#dfn-bufferlevel">bufferLevel</a>;
readonly attribute float <a href="#dfn-bufferremainingtime">bufferRemainingTime</a>;
readonly attribute unsigned short <a href="#dfn-status">status</a>;
DOMString <a href="#dfn-getsessionname">getSessionName</a>();
<a href="#idl-if-MediaStreamInfoList">MediaStreamInfoList</a> <a href="#dfn-getmediastreams">getMediaStreams</a>();
};</pre></div><div class="section" id="idl-if-MediaAccessEvent"><div class="section"><h4 class="idl-header" id="idl-defs-MediaAccessEvent">Definition Group <em>MediaAccessEvent</em></h4><dl class="idl-defs"><dt id="idl-defs-MediaAccessEvent-STATUS_OK"><code>STATUS_OK</code></dt><dd>
No error has occured.
</dd><dt id="idl-defs-MediaAccessEvent-STATUS_ERROR_ON_SETUP"><code>STATUS_ERROR_ON_SETUP</code></dt><dd>
Initialization of a
<a class="term" href="#dfn-session">session</a>
failed.
</dd><dt id="idl-defs-MediaAccessEvent-STATUS_ERROR_UNSUPPORTED_MEDIA"><code>STATUS_ERROR_UNSUPPORTED_MEDIA</code></dt><dd>
One of more of the streams within this
<a class="term" href="#dfn-session">session</a>
contains media not supported by the User
Agent.
</dd><dt id="idl-defs-MediaAccessEvent-STATUS_ERROR_CORRUPT_STREAM"><code>STATUS_ERROR_CORRUPT_STREAM</code></dt><dd>
One of more of the streams within this
<a class="term" href="#dfn-session">session</a>
is corrupt and playback is stopped.
</dd></dl></div><div class="section"><h4 class="idl-header" id="idl-meths-MediaAccessEvent">Attributes</h4><dl class="idl-attr"><dt id="dfn-bufferlevel"><code>bufferLevel</code>
of type
unsigned long, readonly</dt><dd><p>
Specifies a percentage value of the current buffer level. This value is only of
relevance for
'<a href="#event-DataReceptionProgress" class="event-name">DataReceptionProgress</a>'
events. If the
<a class="term" href="#dfn-session">session</a>
contains multiple streams, then the reported value is the minimum
buffer level over all the streams of the
<a class="term" href="#dfn-session">session</a>
.
</p></dd><dt id="dfn-bufferlevelvalid"><code>bufferLevelValid</code>
of type
boolean, readonly</dt><dd><p>
If
<code>false</code>
the buffer level is unknown and the value of
<code>bufferLevel</code>
<em class="rfc2119" title="Keyword in RFC 2119 context">SHOULD</em> be ignored.
</p></dd><dt id="dfn-bufferremainingtime"><code>bufferRemainingTime</code>
of type
float, readonly</dt><dd><p>
Specifies the playing time (in seconds) of the current content of buffer.
This value is only of relevance for
'<a href="#event-DataReceptionProgress" class="event-name">DataReceptionProgress</a>'
events. If the
<a class="term" href="#dfn-session">session</a>
contains multiple streams, then the reported value is the minimum
remaining time over all the streams of the
<a class="term" href="#dfn-session">session</a>
.
</p></dd><dt id="dfn-status"><code>status</code>
of type
unsigned short, readonly</dt><dd><p>
Specifies the error that has occured. One of
<a href="#idl-defs-MediaAccessEvent-STATUS_OK">STATUS_OK</a>
,
<a href="#idl-defs-MediaAccessEvent-STATUS_ERROR_ON_SETUP">STATUS_ERROR_ON_SETUP</a>
,
<a href="#idl-defs-MediaAccessEvent-STATUS_ERROR_UNSUPPORTED_MEDIA">
STATUS_ERROR_UNSUPPORTED_MEDIA</a>
or
<a href="#idl-defs-MediaAccessEvent-STATUS_ERROR_CORRUPT_STREAM">
STATUS_ERROR_CORRUPT_STREAM</a>
<em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be
<a href="#idl-defs-MediaAccessEvent-STATUS_OK">STATUS_OK</a>
for every event type except
'<a href="#event-Error" class="event-name">Error</a>'
.
</p></dd></dl></div><div class="section"><h4 class="idl-header" id="idl-attrs-MediaAccessEvent">Methods</h4><dl class="idl-meth"><dt id="dfn-getmediastreams"><code>getMediaStreams</code></dt><dd><p>
Returns information about the different media streams in this
<a class="term" href="#dfn-session">session</a>
.
</p><dl><dt>No Parameters</dt><dt>Return Value</dt><dd><table><tr><td><code></code></td><td>
The list of streams in this
<a class="term" href="#dfn-session">session</a>
.
</td></tr></table></dd><dt>No Exceptions</dt></dl></dd><dt id="dfn-getsessionname"><code>getSessionName</code></dt><dd><p>
Returns the name of the media access
<a class="term" href="#dfn-session">session</a>
.
</p><dl><dt>No Parameters</dt><dt>Return Value</dt><dd><table><tr><td><code></code></td><td>
The media access
<a class="term" href="#dfn-session">session</a>
name.
</td></tr></table></dd><dt>No Exceptions</dt></dl></dd></dl></div></div>
<p>The Media Access event types are listed below.</p>
<p>Even if a state is not relevant to a particular delivery protocol or implementation, the corresponding events
<em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired. For example, if there is no
<a class="term" href="#dfn-session">session</a>
setup phase, then events
'<a href="#event-BeginSessionSetup" class="event-name">BeginSessionSetup</a>'
,
'<a href="#event-EndSessionSetup" class="event-name">EndSessionSetup</a>'
and
'<a href="#event-DataRequest" class="event-name">DataRequest</a>'
<em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired together in that order.
</p>
<div class="event-definition">
<dl>
<dt>
<a name="event-BeginSessionSetup" id="event-BeginSessionSetup"></a>
<a class="noxref" href="#event-BeginSessionSetup">BeginSessionSetup</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="0" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>BeginSessionSetup</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>A
'<a href="#event-BeginSessionSetup" class="event-name">BeginSessionSetup</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired at the beginning of a streaming
<a class="term" href="#dfn-session">session</a>
.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-EndSessionSetup" id="event-EndSessionSetup"></a>
<a class="noxref" href="#event-EndSessionSetup">EndSessionSetup</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="0" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>EndSessionSetup</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
An
'<a href="#event-EndSessionSetup" class="event-name">EndSessionSetup</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired after a
'<a href="#event-BeginSessionSetup" class="event-name">BeginSessionSetup</a>'
event when the initialisation of
a streaming
<a class="term" href="#dfn-session">session</a>
has been completed.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-DataRequest" id="event-DataRequest"></a>
<a class="noxref" href="#event-DataRequest">DataRequest</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>DataRequest</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
A
'<a href="#event-DataRequest" class="event-name">DataRequest</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired when the UA sends the request for data to the server.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-Playable" id="event-Playable"></a>
<a class="noxref" href="#event-Playable">Playable</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>Playable</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
An
'<a href="#event-Playable" class="event-name">Playable</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired after a
'<a href="#event-DataRequest" class="event-name">DataRequest</a>'
event when enough data is available to start or resume playing.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-DataReceptionProgress" id="event-DataReceptionProgress"></a>
<a class="noxref" href="#event-DataReceptionProgress">DataReceptionProgress</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>DataReceptionProgress</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
The User Agent <em class="rfc2119" title="Keyword in RFC 2119 context">MAY</em> dispatch
'<a href="#event-DataReceptionProgress" class="event-name">DataReceptionProgress</a>'
when data is being received. Information on the current buffer level <em class="rfc2119" title="Keyword in RFC 2119 context">SHOULD</em> be
available.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-NotPlayable" id="event-NotPlayable"></a>
<a class="noxref" href="#event-NotPlayable">NotPlayable</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>NotPlayable</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
An
'<a href="#event-NotPlayable" class="event-name">NotPlayable</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired when not enough data is available to continue playing.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-EndOfDataReception" id="event-EndOfDataReception"></a>
<a class="noxref" href="#event-EndOfDataReception">EndOfDataReception</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>EndOfDataReception</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
An
'<a href="#event-EndOfDataReception" class="event-name">EndOfDataReception</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired when the data reception has finished.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-Stop" id="event-Stop"></a>
<a class="noxref" href="#event-Stop">Stop</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>Stop</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
A
'<a href="#event-Stop" class="event-name">Stop</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired when the data reception has finished and all received data has been
presented.
</p>
<p>
An
'<a href="#event-Stop" class="event-name">Stop</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired when an end condition has been met within the media element, e.g.
one expression in the end attribute has become true or endElement() has been called on the media
element. In that case, the
'<a href="#event-Stop" class="event-name">Stop</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be sent before the endEvent to be dispatched
from the media element.
</p>
</dd>
</dl>
</div>
<div class="event-definition">
<dl>
<dt>
<a name="event-Error" id="event-Error"></a>
<a class="noxref" href="#event-Error">Error</a>
</dt>
<dd>
<table summary="This table contains information about the semantics of the given event type" border="1" cellpadding="2" cellspacing="0">
<tbody>
<tr>
<th rowspan="1" colspan="1">Type</th>
<td rowspan="1" colspan="1" style="background-color:#cfcfcf">
<strong>
<code>Error</code>
</strong>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Namespace</th>
<td rowspan="1" colspan="1" valign="top">
<code>http://www.w3.org/ns/media-access-event#</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Interface</th>
<td rowspan="1" colspan="1" valign="top">
<a href="#MediaAccessEvent-if">
<code>MediaAccessEvent</code>
</a>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Cancelable</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Bubbles</th>
<td rowspan="1" colspan="1" valign="top">Yes</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Target</th>
<td rowspan="1" colspan="1" valign="top">
<code>the media element holding the URL to the delivered content</code>
</td>
</tr>
<tr>
<th rowspan="1" colspan="1">Context info</th>
<td rowspan="1" colspan="1" valign="top">none</td>
</tr>
</tbody>
</table>
<p>
An
'<a href="#event-Error" class="event-name">Error</a>'
event <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be fired when an error occurs. The error code provides information about which kind
of error has occured.
</p>
</dd>
</dl>
</div>
<p>There <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> be at most one event of each of the following types sent within one
<a class="term" href="#dfn-session">session</a>
:
'<a href="#event-BeginSessionSetup" class="event-name">BeginSessionSetup</a>'
,
'<a href="#event-EndSessionSetup" class="event-name">EndSessionSetup</a>'
,
'<a href="#event-DataRequest" class="event-name">DataRequest</a>'
,
'<a href="#event-EndOfDataReception" class="event-name">EndOfDataReception</a>'
,
'<a href="#event-Stop" class="event-name">Stop</a>'
,
'<a href="#event-Error" class="event-name">Error</a>'
</p>
<p>There <em class="rfc2119" title="Keyword in RFC 2119 context">MAY</em> be more than one event of each of the following types sent within one
<a class="term" href="#dfn-session">session</a>
:
'<a href="#event-DataReceptionProgress" class="event-name">DataReceptionProgress</a>'
,
'<a href="#event-Playable" class="event-name">Playable</a>'
,
'<a href="#event-NotPlayable" class="event-name">NotPlayable</a>'
</p>
</div>
<div class="section"><h2 id="MediaStreamInfo-if">5. The MediaStreamInfo interface</h2>
<p>
The
<a href="#idl-if-MediaStreamInfo" class="if-name">MediaStreamInfo</a>
interface stores information about a media stream.
</p>
<div class="boxed"><p><span class="idlTitle">The MediaStreamInfo interface</span></p><pre class="schema" title="The MediaStreamInfo interface">interface <a href="#idl-if-MediaStreamInfo">MediaStreamInfo</a> {
readonly attribute DOMString <a href="#dfn-mediatype">mediaType</a>;
readonly attribute DOMString <a href="#dfn-transport">transport</a>;
readonly attribute DOMString <a href="#dfn-format">format</a>;
};</pre></div><div class="section" id="idl-if-MediaStreamInfo"><div class="section"><h4 class="idl-header" id="idl-meths-MediaStreamInfo">Attributes</h4><dl class="idl-attr"><dt id="dfn-format"><code>format</code>
of type
DOMString, readonly</dt><dd><p>
The format of the media in this stream. E.g. "H264". This attribute <em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em> match
the format as specified by
<a href="http://www.iana.org/">IANA</a>
,
<a href="http://www.iana.org/assignments/media-types/">see
listing</a>
[<cite><a href="#MIME-Media-Types" class="bibref">MIME-Media-Types</a></cite>].
</p></dd><dt id="dfn-mediatype"><code>mediaType</code>
of type
DOMString, readonly</dt><dd><p>
The type of media in this stream, e.g. "video" or "audio". [Editor's note: this wording is
under discussion]
</p></dd><dt id="dfn-transport"><code>transport</code>
of type
DOMString, readonly</dt><dd><p>
The protocol this stream is being delivered over, e.g. "RTP" or "HTTP". [Editor's note: this wording is
under discussion]
</p></dd></dl></div></div>
</div>
<div class="section"><h2 id="MediaStreamInfoList-if">6. The MediaStreamInfoList interface</h2>
<p>
Returns the
<code>index</code>
th item in the collection. If
<code>index</code>
is greater than or equal to the
number of
<a href="#idl-if-MediaStreamInfo" class="if-name">MediaStreamInfo</a>
s in the list, this returns
<code>null</code>
.
</p>
<div class="boxed"><p><span class="idlTitle">The MediaStreamInfoList interface</span></p><pre class="schema" title="The MediaStreamInfoList interface">interface <a href="#idl-if-MediaStreamInfoList">MediaStreamInfoList</a> {
readonly attribute unsigned long <a href="#dfn-length">length</a>;
<a href="#idl-if-MediaStreamInfo">MediaStreamInfo</a> <a href="#dfn-item">item</a>(in unsigned long index);
};</pre></div><div class="section" id="idl-if-MediaStreamInfoList"><div class="section"><h4 class="idl-header" id="idl-meths-MediaStreamInfoList">Attributes</h4><dl class="idl-attr"><dt id="dfn-length"><code>length</code>
of type
unsigned long, readonly</dt><dd><p>
Returns the
<code>number</code>
of items in the collection.
</p></dd></dl></div><div class="section"><h4 class="idl-header" id="idl-attrs-MediaStreamInfoList">Methods</h4><dl class="idl-meth"><dt id="dfn-item"><code>item</code></dt><dd><p>
Returns the
<code>index</code>
th item in the collection. If
<code>index</code>
is greater than or equal
to the number of
<a href="#idl-if-MediaStreamInfo" class="if-name">MediaStreamInfo</a>
s in the list, this returns
<code>null</code>
.
</p><dl><dt>Parameters</dt><dd class="idl-params"><dl><dt><code>index</code>
of type
unsigned long</dt><dd>
Index into the collection.
</dd></dl></dd><dt>Return Value</dt><dd><table><tr><td><code></code></td><td>
The
<a href="#idl-if-MediaStreamInfo" class="if-name">MediaStreamInfo</a>
at the
<code>index</code>
th position in the
<a href="#idl-if-MediaStreamInfoList" class="if-name">MediaStreamInfoList</a>
,
or
<code>null</code>
if that is not a valid
<code>index</code>
.
</td></tr></table></dd><dt>No Exceptions</dt></dl></dd></dl></div></div>
</div>
<div class="section"><h2 id="conform">7. Conformance</h2>
<p>
The key words "<em class="rfc2119" title="Keyword in RFC 2119 context">MUST</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">MUST NOT</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">REQUIRED</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">SHALL</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">SHALL NOT</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">SHOULD</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">SHOULD NOT</em>",
"<em class="rfc2119" title="Keyword in RFC 2119 context">RECOMMENDED</em>", "<em class="rfc2119" title="Keyword in RFC 2119 context">MAY</em>", and "<em class="rfc2119" title="Keyword in RFC 2119 context">OPTIONAL</em>" in this document are to be interpreted as described in
RFC 2119 [<cite><a href="#RFC2119" class="bibref">RFC2119</a></cite>].
</p>
<p>
Unless otherwise specified immediately following the header, all sections in this
document - to the exclusion of examples which are all informative - are normative.
</p>
</div>
<div class="section"><h2 id="example">8. Examples of usage</h2><p><strong>This section is informative.</strong></p>
<p>Three examples to illustrate the usage of streaming events.</p>
<div class="section"><h3 id="example-1">8.1. Simple state information display</h3>
<p>The following example shows the streaming of video. When the playback of the video is stalled due to
network congestion, a simple text is displayed. When the playback resumes, the text is removed.</p>
<div class="boxed"><div><span class="exampleTitle">Example: Using MediaAccessEvents in SVG to display a simple message</span></div><pre class="example" title="Using MediaAccessEvents in SVG to display a simple message"><svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ev="http://www.w3.org/2001/xml-events"
xmlns:se="http://www.w3.org/ns/media-access-event#" width="100%" height="100%"
viewBox="0 0 400 300">
<video id="exampleMovie" type="video/h264" xlink:href="rtsp://example.org/movies/exampleMovie.sdp"
x="0" y="0" width="400" height="300"/>
<text display="none" id="information" fill="white" x="50" y="50" font-size="30">
<set attributeName="display" to="inline" begin="exampleMovie.NotPlayable" fill="freeze"/>
<set attributeName="display" to="none" begin="exampleMovie.Playable" fill="freeze"/>
Buffering
</text>
</svg></pre></div>
</div>
<div class="section"><h3 id="example-2">8.2. Buffering progress bar</h3>
<p>The following example shows streaming of video within svg. When playback of the video is stalled due to a
lack
of video data a progress bar is displayed. The progress bar indicates how much buffering that is needed
before
playback can be resumed. The example is not runnable as is since the intention is to show an example of
using
streaming events, not to give a complete svg example.</p>
<div class="boxed"><div><span class="exampleTitle">Example: Using MediaAccessEvents in SVG to display a buffering progress bar</span></div><pre class="example" title="Using MediaAccessEvents in SVG to display a buffering progress bar"><svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ev="http://www.w3.org/2001/xml-events"
xmlns:se="http://www.w3.org/ns/media-access-event#">
<script type="application/ecmascript"><![CDATA[
function initSetup (evt) {
var setupAnimation = document.getElementById('setupAnimation');
setupAnimation.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "visible");
setupAnimation.beginElement();
}
function exitSetup (evt) {
var setupAnimation = document.getElementById('setupAnimation');
setupAnimation.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "hidden");
setupAnimation.endElement();
}
function bufferStart (evt) {
var progressBar = document.getElementById('progressBar');
progressBar.setAttributeNS("http://www.w3.org/2000/svg", "width", "0");
progressBar.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "visible");
var bufferAnimation = document.getElementById('bufferAnimation');
bufferAnimation.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "visible");
bufferAnimation.beginElement();
}
function bufferProgress (evt) {
var progressBar = document.getElementById('progressBar');
progressBar.setAttributeNS("http://www.w3.org/2000/svg", "width", 100*(evt.bufferFillLevel));
}
function bufferComplete (evt) {
var progressBar = document.getElementById('progressBar');
progressBar.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "hidden");
var bufferAnimation = document.getElementById('bufferAnimation');
bufferAnimation.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "hidden");
bufferAnimation.endElement();
}
]]></script>
<video id="exampleMovie" type="video/h264" xlink:href="rtsp://example.org/movies/exampleMovie.sdp"
x="0" y="0" width="400" height="300">
<handler type="application/ecmascript" ev:event="me:BeginSessionSetup">
initSetup(evt);
</handler>
<handler type="application/ecmascript" ev:event="me:EndSessionSetup">
exitSetup(evt);
</handler>
<handler type="application/ecmascript" ev:event="me:NotPlayable">
bufferStart(evt);
</handler>
<handler type="application/ecmascript" ev:event="me:DataRequest">
bufferStart(evt);
</handler>
<handler type="application/ecmascript" ev:event="me:DataReceptionProgress">
bufferProgress(evt);
</handler>
<handler type="application/ecmascript" ev:event="me:Playable">
bufferComplete(evt);
</handler>
</video>
<g> ...
<animate id="bufferAnimation" ... />
</g>
<g> ...
<animate id="setupAnimation" ... />
</g>
<rect id="progressBar" ... />
</svg></pre></div>
</div>
<div class="section"><h3 id="example-3">8.3. Stream info box</h3>
<table summary="Layout table" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td style="width:50%" rowspan="1" colspan="1" valign="top">This example shows streaming of video
within svg. An
svg-button is available and when clicked it displays a box with information about the video
stream. As with
the example above this one isn't runnable as is since the svg markup isn't complete. The
image to the right
shows a possible rendering of the info box in this example.</td>
<td rowspan="1" colspan="1" valign="top">
<img src="images/example2.jpg" alt="Example of info box" width="385" height="289" />
</td>
</tr>
</tbody>
</table>
<div class="boxed"><div><span class="exampleTitle">Example: Using MediaAccessEvents in SVG to display a stream info box</span></div><pre class="example" title="Using MediaAccessEvents in SVG to display a stream info box"><svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ev="http://www.w3.org/2001/xml-events"
xmlns:se="http://www.w3.org/ns/media-access-event#">
<script type="application/ecmascript"><![CDATA[
function sessionSetupComplete (evt) {
var sessionName, sessionProtocol;
var streamFormat, mediaType;
sessionName = evt.sessionName;
if (sessionName == 0) sessionName = "No session name available";
var streamList = evt.getMediaStreams();
var stream = streamList.item(0);
if (stream == 0){
sessionProtocol = "N/A";
streamFormat = "N/A";
mediaType = "N/A";
}
else{
sessionProtocol = stream.transport;
streamFormat = stream.format;
mediaType = stream.mediaType;
}
document.getElementById('sessionNameText').textContent = "Session name: " + sessionName;
document.getElementById('sessionProtocolText').textContent = "Streaming protocol: " + sessionProtocol;
document.getElementById('sessionTypeText').textContent = "Streaming media: " + mediaType;
document.getElementById('sessionFormatText').textContent = "Format/codec: " + streamFormat;
}
function showInfo (evt) {
var infoBox = document.getElementById('infoBox');
setupAnimation.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "visible");
}
function hideInfo (evt) {
var infoBox = document.getElementById('infoBox');
setupAnimation.setAttributeNS("http://www.w3.org/2000/svg", "visibility", "hidden");
}
]]></script>
<video id="exampleMovie" type="video/h264" xlink:href="rtsp://example.org/movies/exampleMovie.sdp"
x="0" y="0" width="400" height="300">
<handler type="application/ecmascript" ev:event="me:EndSessionSetup">
sessionSetupComplete(evt);
</handler>
</video>
<g id="infoButton"> ...
<handler type="application/ecmascript" ev:event="ev:DOMActivate">
showInfo(evt);
</handler>
</g>
<g id="infoBox"> ...
<text id="sessionNameText" ...></text>
<text id="sessionProtocolText" ...></text>
<text id="sessionTypeText" ...></text>
<text id="sessionFormatText" ...></text>
<g id="okButton"> ...
<handler type="application/ecmascript" ev:event="ev:DOMActivate">
hideInfo(evt);
</handler>
</g>
</g>
</svg></pre></div>
</div>
</div>
<div class="section"><h2 id="ack">9. Acknowledgements</h2><p><strong>This section is informative.</strong></p>
<p>
The authors would like to thank Cyril Concolato for his thorough review and excellent contribution.
We would also like to thank Robin Berjon for ReSpec, the editorial framework upon
which this specification is written.
</p>
</div>
<div class="section"><h2 id="bibref">A. References</h2>
<dl class="bibliography">
<dt id="DOM3EV">DOM3EV</dt><dd><cite><a href="http://www.w3.org/TR/DOM-Level-3-Events/">Document Object Model (DOM) Level 3 Events Specification</a></cite>,
<span class="person">Philippe Le Hégaret (W3C)</span>, and <span class="person">Tom Pixley (Netscape Communications Corporation)</span>.</dd><dt id="MIME-Media-Types">MIME-Media-Types</dt><dd><cite><a href="http://www.iana.org/assignments/media-types/">IANA MIME Media Types</a></cite>,
</dd><dt id="RFC2119">RFC2119</dt><dd><cite><a href="http://www.ietf.org/rfc/rfc2119.txt">Key words for use in RFCs to Indicate Requirement Levels</a></cite>,
<span class="person">S. Bradner</span>.</dd><dt id="SVGT12">SVGT12</dt><dd><cite><a href="http://www.w3.org/TR/SVGMobile12/">Scalable Vector Graphics (SVG) Tiny 1.2 Specification</a></cite>,
<span class="person">Ola Andersson <<a href="mailto:ola.andersson@ikivo.com">ola.andersson@ikivo.com</a>></span>, <span class="person">Robin Berjon <<a href="mailto:robin.berjon@expway.fr">robin.berjon@expway.fr</a>></span>, <span class="person">Jon Ferraiolo <<a href="mailto:jon.ferraiolo@adobe.com">jon.ferraiolo@adobe.com</a>></span>, <span class="person">Vincent Hardy <<a href="mailto:vincent.hardy@sun.com">vincent.hardy@sun.com</a>></span>, <span class="person">Scott Hayman</span>, <span class="person">Dean Jackson <<a href="mailto:dean@w3.org">dean@w3.org</a>></span>, <span class="person">Craig Northway <<a href="mailto:craign@cisra.canon.com.au">craign@cisra.canon.com.au</a>></span>, and <span class="person">Antoine Quint <<a href="mailto:aq@fuchsia-design.com">aq@fuchsia-design.com</a>></span>.</dd></dl>
</div>
</body>
</html>