Post Formats are a big feature in WordPress 3.6. What you may not know is: there is now native support for Audio and Video in core! There has been great support for embeds by way of WP_Embed and oEmbed providers for a while, but, if you wanted to play an MP3 from your Media Library, you had to install a plugin. Supporting audio and video in core gives bands, podcasters, vloggers, et al the ability to easily and beautifully expresses themselves through sounds and moving pictures without using an external service.
How does this work?
At the core of the experience is the fantastic library, MediaElement.js. MediaElement is the facade layer that gives us maximum file support and cross-browser compatibility. While some libraries require a Flash-only solution to make your media work cross-environment, MediaElement lets you use HTML5 audio / video tags in every browser, and, only when necessary, will use a Flash or Silverlight plugin in the background to make incompatible media work. Translation, things like this: <audio> tag works in old IE, Windows Media files work in Chrome.
MediaElement uses the same HTML markup, regardless of playback implementation, and you can use CSS to skin the players.
MediaElement’s great, but we don’t want to be locked in to one external library forever. Instead of using MediaElement-specific markup everywhere, we expose audio and video markup through shortcodes: [audio] and [video].
For the following scenarios:
I have an old post that has a video in the Media Library attached to it, and I want to use the new shortcode: [video]
I have the URL for a video, from the Media Library or external, that I want to play: [video src="video-source.mp4"]
I have a source URL and fallbacks for other HTML5-supported filetypes: [video width="600" height="480" mp4="source.mp4" ogv="source.ogv" webm="source.webm"]
Same goes for audio:
I have an old post that has an audio file in the Media Library attached to it, and I want to use the new shortcode: [audio]
I have the URL for an MP3, from the Media Library or external, that I want to play: [audio src="audio-source.mp3"]
I have a source URL and fallbacks for other HTML5-supported filetypes: [audio mp3="source.mp3" ogg="source.ogg" wav="source.wav"]
Shortcodes focus on the “what” and abstract the “how.” If you want to use a library that is not MediaElement, you can! Just look at what to filter: here
There are also new embed handlers for audio and video. Using them is easy as dropping a media link on a line by itself in the editor:
I like this song because it is really cool!
Works for both audio and video with URLs matching the allowed (and filterable) list of extensions (see: here and here)
Using the new post formats UI, it is even easier to get directly at the audio and video in your Media Library. When selecting, the media modal opens to your library, filtered by media type.
In previous versions of WP, you could upload audio and video, but we were not generating metadata like we do for images. In 3.6, using the getID3 library, we are able to extract data from audio and video like cover art, song length, artist, album, song title, genre, codec, etc. It’s pretty great. We will soon be exposing more of this data in the admin as well, along with inline previews on the Edit Media page:
Themers can get in on the action, too, using structured-post-formats in their theme (Twenty Thirteen is a great place to look). The admin gives users flexibility when associating media with a post. the_post_format_audio() and the_post_format_video() will automagically retrieve and output your media in the front end.