You can see this nifty technique in an article called "Video for Everybody!" by its inventor, Kroc Camen. The code for this is as hideous as you'd expect for a transitional hack, but it works everywhere a Flash Player is installed-which is almost everywhere. Remember that the contents of the element can contain markup, like the text and links in the previous example? Because the MP4 file type can also be played by the Flash player plugin, you can use the MP4 movie in combination as a fallback for Internet Explorer 8 and older versions of other browsers. But if you're prepared to rely on plugins, you can ensure that users of older browsers can still experience your content in a way that is no worse than they currently get. Older browsers can't play native video or audio, bless them. This has bitten me on the bottom a few times. A browser that understands HTML5 video but can't play any of the formats that your code points to will not display the "fallback" content between the tags. The content between the tags is fallback content only for browsers that do not support the element at all. What about users of legacy browsers-including Internet Explorer 8 and older? Video for legacy browsers OK, so that's native HTML5 video for all users of modern browsers. Inside the element is our fallback message, including links to both formats for browsers that can natively deal with neither video type but which is probably on top of an operating system that can deal with one of the formats, so the user can download the file and watch it in a media player outside the browser. Higher profiles require more CPU to decode, but they are better compressed and take less bandwidth. The codec strings for H.264 and AAC are more complicated than those for Ogg because there are several profiles for H.264 and AAC. If you miss out on the type attribute, the browser downloads a small bit of each file before it figures out that it is unsupported, which wastes bandwidth and could delay the media playing. Notice that we used quotation marks around these parameters. We could also offer a WebM video here as a high-quality royaltyfree option. Line 2 offers an Ogg Theora video and uses the type attribute to tell the browser what kind of container format is used (by giving the file's MIME type) and what codec was used for the encoding of the video and the audio stream. Line 1 tells the browser that a video is to be inserted and to give it default controls. 5 Please download the video in Ogg or mp4 format. Note that in this case we do not provide a src attribute in the media element itself: 1 2 3 4 Your browser doesn't support video. Instead of using the single src attribute, you nest separate elements for each encoding with appropriate type attributes inside the or element and let the browser download the format that it can display. Then, you tie these separate versions of the file to the media element. To do this, you need to encode your multimedia twice: once as Theora and once as H.264 in the case of video, and in both Vorbis and MP3 for audio. ![]() Let's not repeat the mistakes of the old "Best viewed in Netscape Navigator" badges on websites. The rule is: provide both royalty-free (webM or Theora) and H.264 video in your pages, and both Vorbis and MP3 audio so that nobody gets locked out of your content. webm for high quality video, once browser support is there. VP8 will be included in Adobe's Flash Player and every YouTube video will be in webM format. IE9 will, if the codec is separately installed. ![]() Opera, Firefox and Chrome have announced it will support it. This is a very high-quality codec, and when combined with Vorbis in a container format based on the Matroska format, it's collectively known as "webM". Confused?Īs we were finishing this book, Google announced it is opensourcing a video codec called VP8. Google Chrome supports Theora and H.264 video, and Vorbis and MP3 audio. Microsoft has announced that IE9 will also support H.264, which is also supported on iPhone and Android. Safari doesn't, preferring instead to provide native support for the H.264 video codec and MP3 audio. Opera and Firefox support Theora and Vorbis. This leaves us with a fragmented situation. However, these codecs were dropped from the HTML5 spec after Apple and Nokia objected, so the spec makes no recommendations about codecs at all. Vorbis is a codec used by services like Spotify, among others, and for audio samples in games like Microsoft Halo, it's often used with Theora for video and combined together in the Ogg container format. Learn More Buy Codecs-the horror, the horrorĮarly drafts of the HTML5 specification mandated that all browsers should at least have built-in support for multimedia in two codecs: Ogg Vorbis for audio and Ogg Theora for movies.
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