[whatwg] Scripted querying of <video> capabilities

[Tim Starling]

Kristof Zelechovski wrote:
> Why do we need an API to test UA media capabilities?  What purpose would
> such an API serve except for displaying the media to the user - a task which
> can already be achieved without a dedicated API?
>   

It is useful for websites that wish to use a new or unpopular format
(such as Ogg Theora). If the client does not support the format in
question using <video>, it can fall back to another method.

I am employed to work on just such a website (Wikipedia). I maintain a
Java applet called Cortado that can be used to play Theora/Vorbis
videos, and I wrote an extension for MediaWiki called OggHandler which
uses JavaScript and an extensive series of client-side fallbacks
(including Cortado and <video>) to display Theora/Vorbis files to the user.

João Eiras wrote:
>
> Then the browser does not support <video>. The spec mandates both
> <video> element support + ogg theora support. Else the implementation
> is incomplete. 

I'm afraid you have missed the news: the HTML working group balked, and
have removed all references to Theora from the draft (except as an
example alongside MPEG). Thus they have ensured that some <video>
implementations will not support Ogg Theora. That is why we need a query
interface: so that we can fall back to <applet> when the client only
supports proprietary codecs.

-- Tim Starling