- From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Date: Wed, 28 Jan 2009 09:53:15 +1100
- To: David Singer <singer@apple.com>
- Cc: Michael Hausenblas <michael.hausenblas@deri.org>, Media Fragment <public-media-fragment@w3.org>, Raphaël Troncy <Raphael.Troncy@cwi.nl>
And having said that - maybe we can do something else for retrieving a thumbnail than a fragment request. E.g. something like http://www.example.com/movie.ogg?t=5m2s&type=text/png This is a different resource to the movie file, so it can have a different mime type. Maybe we should consider taking advantage of the possibilities that query and fragment identifiers both give us? Cheers, Silvia. On Wed, Jan 28, 2009 at 9:45 AM, Silvia Pfeiffer <silviapfeiffer1@gmail.com> wrote: > I agree with Dave - the only problem where we are potentially changing > mime types is the request for a picture out of a video. We should > focus on this discussion. And.. no, I haven't got a good answer yet. > :) > > Silvia. > > > On Wed, Jan 28, 2009 at 1:48 AM, David Singer <singer@apple.com> wrote: >> >> At 14:36 +0000 27/01/09, Michael Hausenblas wrote: >>> >>> Dave, >>> >>> >>>> a) the MIME type of the requested fragment is the >>>> same as that of the original resource; yes, that >>>> might result in one-frame movies, and so on; >>> >>> Sounds good. Didn't think about this one yet. But how do we technically do >>> this? I fear I don't understand. Could you be more precisely on this >>> option, >>> please? >>> >> >> Well, I am trying hard to think of a case *in multimedia* where the >> statement >> "the type of a piece of X *cannot* be the same as the type of X" >> would be true. >> >> The obvious problem area is if you select a time-point in a video track of a >> movie, then a fragment cast as a movie would have zero duration -- it's more >> sensibly a picture. Unfortunately, zero duration frames are explicitly >> forbidden in MP4, 3GP etc. (since they can make the visual display at a >> given time ambiguous). >> >> But this gets semantically tricky if there is sound; what is the correct >> representation of a point in time of a sound track? It's not right to drop >> it from the fragment (oof, we'd need media-type rules for what types get >> dropped and what don't). >> >> This is steering me towards wondering if a piece of X, in time, necessarily >> has some extension in time, i.e. a time-point is not a fragment (can you see >> a zero-width character if you meet one in the street?). >> -- >> David Singer >> Multimedia Standards, Apple Inc. >> >> >
Received on Tuesday, 27 January 2009 22:53:52 UTC