Re: comments on draft-barth-mime-sniffing

Simon Pieters wrote:
> On Fri, 12 Jun 2009 20:55:29 +0200, Ian Hickson <> wrote:
> >I've updated HTML5 to require that Content-Types of types that are not
> >supported cause the resource to be ignored (even if it would otherwise be
> >supported).
> If a UA does not know what is not supported, is it reasonable to consider  
> anything that is not video/* or audio/* to be not supported?

For video, content negotiation is probably going to end up being done
in Javascript rather than HTTP, or by User-Agent recognition.

The Content-Type of video/* simply doesn't provide enough information,
in practice to tell if the file can be played or not by a particular
browser / video player.  The file itself must be read, to determine
the codecs used.  Of course the client must understand the file
format, but the tough part is understanding the codec format inside
the file format, which is just a container.

Although there is an RFC specifying MIME sub-types to video/*
describing the codecs, I don't see any way to sensibly fit that into
HTTP's Accept: content-negotiation.

-- Jamie

Received on Tuesday, 16 June 2009 15:26:26 UTC