[whatwg] Serving up Theora <video> in the real world
simonp at opera.com
Tue Jul 28 01:26:45 PDT 2009
On Tue, 28 Jul 2009 02:39:46 +0200, Andrew Scherkus <scherkus at google.com>
>> On Sun, 12 Jul 2009, Philip Jägenstedt wrote:
>> > Not that I except this discussion to go anywhere, but out of
>> curiosity I
>> > checked how Firefox/Safari/Chrome actually implement canPlayType:
>> > http://wiki.whatwg.org/wiki/Video_type_parameters#Browser_Support
>> > Firefox is conservative and honest (except maybe for "audio/wav;
>> > codecs=0", what could you do with the RIFF DATA chunk?) Safari gets
>> > maybe/probably backwards compared to what the spec suggests. Chrome
>> > seems to ignore the codecs parameter, claiming "probably" even for
>> > codecs. Authors obviously can't trust the distinction between "maybe"
>> > and "probably" to any extent.
>> That certainly is unfortunate.
> Thanks for calling us out :)
> We've addressed this in our latest builds. We now fall somewhere between
> Firefox and Safari in terms of conservativeness and honesty.
> We still give bogus codecs a "maybe" if the container is supported, since
> that seems to be what the spec suggests.
That doesn't match my reading of the spec...
The spec says
"The canPlayType(type) method must return the empty string if type is a
type that the user agent knows it cannot render;"
"A type that the user agent knows it cannot render is one that describes a
resource that the user agent definitely does not support, for example
because it doesn't recognize the container type, or it doesn't support the
> A "probably" is only for both a
> container and codec match.
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