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RE: ACTION-123: Silvia to come up with ABNF for header syntax - FINISHED

From: DENOUAL Franck <Franck.Denoual@crf.canon.fr>
Date: Thu, 20 May 2010 10:50:23 +0200
To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Media Fragment <public-media-fragment@w3.org>
Message-ID: <1337E6FD97CF8845A4C949F24AACFC4601DE973461@Nina.crf.canon.fr>
Hi all,

I have some comments/remarks on the nice ABNF syntax for HTTP headers provided by Silvia:
1- Should each grammar be self-descriptive or not ? (I would personally think: yes)
If yes, the following items (from MF URI and HTTP RFC) should be redefined:
-> byte-ranges-specifier
-> time-prefix, trackprefix, nameprefix
-> trackparam, nameparam
-> deftimeformat, smpteformat, clockformat      
-> npt-sec (only ? not npttime?), frametime, datetime
-> token
-> byte-range-resp-spec
If no => at least a reference to the ABNF syntax for URI and to HTTP RFC should be inserted in HTTP ABNF syntax.

2- Is the problem of introducing the new header "Content-Range-Mapping" fixed ? Was raised in : http://lists.w3.org/Archives/Public/public-media-fragment/2010Mar/0155.html

3- Wouldn't it be useful to allow: Range : "include-setup" ? 
Currently at least one fragment-range has to be provided.
Otherwise, fragment specifier could be formulated as :
fragment-specifier  = "include-setup" | fragment-range *( "," fragment-range ) [ ";" "include-setup" ]
This also applies to Content-Range-Mapping.

4- In the different xxx-mapping-options, shouldn't we let the possibility to put "/*" (or "/*-*") at the end, in case the start/end durations are unknown or the server couldn't get them ?

--
    Franck.


 
> -----Original Message-----
> From: public-media-fragment-request@w3.org [mailto:public-media-fragment-
> request@w3.org] On Behalf Of Silvia Pfeiffer
> Sent: jeudi 20 mai 2010 03:32
> To: raphael.troncy@eurecom.fr
> Cc: Media Fragment
> Subject: Re: ACTION-123: Silvia to come up with ABNF for header syntax - FINISHED
> 
> 2010/5/20 RaphaŽl Troncy <raphael.troncy@cwi.nl>:
> > Hi Silvia,
> >
> >> I have worked on the ABNF for the HTTP headers and they are now all
> >> part of the spec at the appropriate locations.
> >> I have also aggregated them into an additional appendix, see
> >>
> >> http://www.w3.org/2008/WebVideo/Fragments/WD-media-fragments-
> spec/#collected-syntax-http
> >> .
> >
> > Thanks, great work!
> > I'm wondering whether you have re-used some definitions from HTTP 1.1 Bis,
> > http://www.ietf.org/rfc/rfc2616.txt or not?
> 
> Yes, I have started from the relevant definitions there and extended
> them where necessary. I have put links in the document where I have
> done so.
> 
> 
> >> I will not claim that everything I wrote is correct, so please go and
> >> check back with your understanding and in particular with your
> >> implementations. This is meant for us to take the next step. I'd be
> >> particularly interested in having Yves counter-check, since he seems
> >> to be the ABNF expert amongst us. :-)
> >
> > I will roll the ball to Yves!
> 
> Also ask your plugin developer if he can cross-read!
> 
> Cheers,
> Silvia.
Received on Thursday, 20 May 2010 08:51:04 GMT

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