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[whatwg] Javascript API to query supported codecs for <video> and <audio>

From: <j@oil21.org>
Date: Wed, 18 Jun 2008 13:10:37 +0200
Message-ID: <1213787437.7248.8.camel@BlackBook>
On Wed, 2008-06-18 at 17:38 +0700, Philip J?genstedt wrote:
> Implementation-wise it might be less than trivial to return an
> exhaustive list of all supported mime-types if the underlying framework
> doesn't use the concept of mime-types, but can say when given a few
> bytes of the file whether it supports it or not. Allowing JavaScript to
> second-guess this seems like a potential source of incompatibility.
> Isn't it sufficient to look for MEDIA_ERR_DECODE and add fallback
> content when that happens?
i imagined something that would use the ?type string used in <source>
so i can do:
 canDecode('video/mp4; codecs="avc1.42E01E, mp4a.40.2"')
?or
 canDecode('video/ogg; codecs="theora, vorbis"')

while waiting for ?MEDIA_ERR_DECODE might be an option,
it sounds to me that that would involve a network connection being made,
the video being buffered and after that the media engine failing, this
takes to long to make a presentation decision based on it.

j
Received on Wednesday, 18 June 2008 04:10:37 UTC

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