Notify user agent available fragment

Hello workgroup,

Pardon my ignorance if this question was already addressed. There  
seems to be no reference in the working draft, but I realize you could  
consider this topic out of scope.

How do you see the user-agent being notified in advance of the  
fragmentation possibilities of a certain resource?

For example, one video on a server might contain an AUDIO track (and  
thus the possibility to retrieve audio fragments), while the other  
video might not contain this track. As a second example, that first  
video might have a VIDEO track with keyframe-interval of two seconds  
and the second video might have a VIDEO track with keyframe-interval  
of four seconds. The server might not be able to return a 2-second  
fragment of the second video without transcoding (which should be  

User agents would like to have this exact information in advance,  
without relying on fallback actions (e.g. the server returning an  
error in the first example and a 4-second fragment in the second  
example). They would be able to present the appropriate interface and  
apply the appropriate resource fetching heuristics.

Kind regards,
Jeroen Wijering

Received on Sunday, 2 May 2010 19:29:36 UTC