mime types and video/audio files (was Re: Review of the thumbnailer spec)

[Sven Neumann]

Hi,

On Fri, 2009-05-22 at 12:53 +0200, Philip Van Hoof wrote:

> Now if I'd have a GStreamer (or whatever media framework) library call
> like:
> 
> gboolean g_streamer_do_you_support (const gchar *that_string)
> 
> Then that would be great.
> 
> Regretfully right now it's basically a: try, if not, we didn't support
> it, sorry. That's of course more expensive than above query.
> 
> What I'm most concerned about is knowing what I can give it, and what I
> can't give it. In a fast way, preferably. And an equally fast way to,
> given a GFile (or a URI), know that string that I can use to query.
> 
> Over HTTP, SMTP and IMAP I guess only Content-Type is standardized for
> this. Which is why I naturally think about that string for making it
> useful for this purpose.

Usually multimedia frameworks specify this in one way or another. DLNA
for example defines media format profiles to describe media files and
streams. This is done mainly for the purpose of finding out whether a
certain media-renderer will be able to play back some content. The MIME
type is part of this specification, but it is by no means sufficient.
Even if you went for complex MIME types as you suggested, that wouldn't
be sufficient. You usually need to know the container, the codec, number
of channels, bit-rate and more. Are you seriously suggesting to encode
all this in the MIME type?


Sven