HTML5 Multimedia: where we are, where we're going

HTML5 multimediaWhere we are, where we're goingBruce Lawson

Anne van Kesteren annevk at opera.comWed Feb 28 05:47:56 PST 2007

Hi,Opera has some internal expiremental builds with an implementation of a <video> element. The element exposes a simple API (for the moment) much like the Audio() object: play() pause() Stop()

The idea is that it works like <object> except that it has special <video> semantics much like <img> has image semantics. In markup you could prolly use it as follows:

<figure> <video src=news-snippet.ogg> ... </video> <legend>HTML5 in BBC News</legend> </figure>

I attached a proposal for the element and as you can see there are still some open issues. The element and its API are of course open for debate. We're not enforcing this upon the world ;-)

Cheers,http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2007-February/009702.html

<object width="425" height="344"><param name="movie"

value="http://www.example.com/v/9sEI1AUFJKw&hl=en&fs=1&"></param>

<param name="allowFullScreen" value="true"></param>

<param name="allowscriptaccess" value="always"></param>

<embed src="http://www.example.com/v/9sEI1AUFJKw&hl=en&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

<video src=pudding.webm controls autoplay poster=poster.jpg width=320 height=240> <a href=video.webm>Download movie</a></video>

<audio src=bieber.ogg controls autoplay> <a href=bieber.ogg>Download horrid pap</a></audio>

<video src=pudding.webm loop>

<audio src=bieber.ogg preload><audio src=bieber.ogg preload=auto><audio src=bieber.ogg preload=none><audio src=bieber.ogg preload=metadata>

video as native object...why is it important?

● keyboard accessibility built-in● “play nice” with rest of the page● Simple API for controls

"In addition to giving video an HTML element, we must also agree on a baseline video format that will be universally supported, just like the GIF, JPEG and PNG image format are universally supported. It's important that the video format we choose can be supported by a wide range of devices and that it's royalty-free (RF). RF is a well-established principle for W3C standards."

http://people.opera.com/howcome/2007/video/

Ogg Theora

“free and open”, no licensing/royaltiesnot many tools for it, not web optimised

MP4 / H.264

ubiquitous, patent encumbered, licensing/royalties, hardware accelerated

WebM

"open and royalty-free", web optimised, hardware acceleration on its way

video formats

webM Ogg/ Theora mp4/ h264

Opera yes yes

Chrome yes yes Nope (Chrome.soon)

Firefox Yes (FF4) yes

Safari yes

IE9 Yes (if installed) yes

The politics of codecs

audio formats

mp3 Ogg/ Vobis wav

Opera yes yes

Chrome yes yes

Firefox yes yes

Safari yes yes

IE9 yes yes

Giving everybody video

<video controls autoplay poster=… width=… height=…><source src=pudding.mp4 type=video/mp4><source src=pudding.webm type=video/webm><!-- fallback content -->

</video>

<video controls poster="…" width="…" height="…"><source src="movie.mp4" type="video/mp4" /><source src="movie.webm" type="video/webm" /><source src="movie.ogv" type="video/ogg" /><object width="…" height="…" type="application/x-

shockwave-flash" data="player.swf"><param name="movie" value="player.swf" /><param name="flashvars" value=" … file=movie.mp4" /><!-- fallback content -->

</object></video>

still include fallback for old browsershttp://camendesign.com/code/video_for_everybody

Help

● archive.org converts and hosts creative-commons licensed media

● vid.ly has a free conversion/ hosting service (max 1GB source file) see vid.ly/5u4h3e

● Miro video converter is a drag and drop GUI skin on FFMPEG

powerful (simple) API

www.w3.org/TR/html5/video.html#media-elements

controlling <video> with JavaScript

var v = document.getElementByTagName('video')[0];

v.play();v.pause();v.volume = … ;v.currentTime = … ;…

events fired by <video>var v = document.getElementById('player');v.addEventListener('loadeddata', function() { … }, true)v.addEventListener('play', function() { … }, true)v.addEventListener('pause', function() { … }, true)v.addEventListener('timeupdate', function() { … }, true)v.addEventListener('ended', function() { … }, true)…

Race condition:html5demos.com/video

video media queries

<video controls><source src=hi-res.ogv media="(min-device-width:800px)"><source src=lo-res.ogv></video>

http://dev.w3.org/html5/spec/video.html#the-source-element

Full-screen video● Currently, WebkitEnterFullscreen();● May 11, WebKit announced it's implementing Gecko API https://wiki.mozilla.org/Gecko:FullScreenAPI

● Opera likes this approach, too

<video> accessibility

WebM release does not support subtitles

http://code.google.com/p/webm/issues/detail?id=11Egg image Kacper "Kangel" Aniołek http://commons.wikimedia.org/wiki/File:Egg.jpg

WHATWG / W3C RFC will release guidance on subtitles and other overlays in HTML5 <video> in the near future. WebM intends to follow that guidance.

<track> element

<video controls poster=… width=… height=…><source src=movie.webm type=video/webm><track src=subtitles-en.vtt kind=subtitles srclang=en><track src=subtitles-de.vtt kind=subtitles srclang=de><!-- fallback content -->

</video>

http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#the-track-element

webVTTWEBVTT FILE

101:23:45,678 --> 01:23:46,789Hello world!

201:23:48,910 --> 01:23:49,101HelloWorld!www.iandevlin.com/blog/2011/05/html5/webvtt-and-video-subtitlesblog.gingertech.net/2011/03/29/webvtt-explained/

WebVTT formatting

Supports positioning of text

Supports <b> and <i>

Colouring individual speakers

Support vertical text

Supports RTL

Supports ruby annotations

http://www.whatwg.org/specs/web-apps/current-work/webvtt.html

<track> polyfillhttp://www.delphiki.com/html5/playr/

Synchronising media elementsEach media element can have a MediaController. A MediaController is an object that coordinates the playback of multiple media elements, for instance so that a sign-language interpreter track can be overlaid on a video track, with the two being kept in sync....

Media elements with a MediaController are said to be slaved to their controller. The MediaController modifies the playback rate and the playback volume of each of the media elements slaved to it, and ensures that when any of its slaved media elements unexpectedly stall, the others are stopped at the same time.

When a media element is slaved to a MediaController, its playback rate is fixed to that of the other tracks in the same MediaController, and any looping is disabled.

http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#synchronising-multiple-media-elements

http://www.w3.org/WAI/PF/HTML/wiki/Media_Multitrack_Media_API

How mature is all this?Looping latency

people.opera.com/patrickl/experiments/audio/hacky-looper/

HTML5 video issues on the iPad and how to solve themblog.millermedeiros.com/2011/03/html5-video-issues-on-the-ipad-and-how-to-solve-them/

Unsolved HTML5 video issues on iOShttp://blog.millermedeiros.com/2011/04/unsolved-html5-video-issues-on-ios/

Audio Sprites (and fixes for iOS) remysharp.com/2010/12/23/audio-sprites/

“...extending the language to better support Web applications … This puts HTML in direct competition with other technologies intended for applications deployed over the Web, in particular Flash and Silverlight.”

Ian Hickson, Editor of HTML5http://lists.w3.org/Archives/Public/public-html/2009Jan/0215.html

DRM on HTML5 without changes

Henri Sivonen

lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2010-July/027051.html

getUserMedia API(previously known as "HTML5 <device>")

<video autoplay></video><script>var video = document.querySelector(video);

If (navigator.getUserMedia) {navigator.getUserMedia('video',successCallback, errorCallback);

function successCallback(stream) { video.src = stream; }...</script>

my.opera.com/core/blog/2011/03/23/webcam-orientation-preview

Thanks Mike Taylor @miketaylr for JS help, and Patrick Lauke

@patrick_h_lauke for the Hixie voice. (What does that "H" stand for?)

Ian Devlin @iandevlin and Silvia Pfeiffer @silviapfeiffer for webVTT advice

Philip Jägenstedt @foolip and Simon Pieters @zcorpan for implementing/ QA-ing multimedia in Opera and explaining it

to me slowly and patiently