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Re: Track fragments

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Thu, 18 Feb 2010 00:00:45 +1100
Message-ID: <2c0e02831002170500m54824a10g231a28b8a9147d04@mail.gmail.com>
To: Davy Van Deursen <davy.vandeursen@ugent.be>
Cc: DENOUAL Franck <Franck.Denoual@crf.canon.fr>, public-media-fragment@w3.org
On Wed, Feb 17, 2010 at 11:58 PM, Davy Van Deursen
<davy.vandeursen@ugent.be> wrote:
> On feb 17, 2010 at 13:46, Silvia Pfeiffer wrote:
>> On Wed, Feb 17, 2010 at 11:08 PM, Davy Van Deursen
>> > On feb 16, 2010 at 20:33, Silvia Pfeiffer wrote:
>>
>> > In
>> > case of the former, I do agree that there are problems with Ogg
>> > regarding track selection (note that a solution for MP4 was
>> > discussed here by Dave Singer [1]).
>>
>> Dave only talks about the time dimension there, too. I am not sure MP4
>> could more easily deal with tracks retrieved through byte range
>> requests than Ogg does. But I don't know enough about the moov
>> containers.
>
> Once you get the full header of an MP4 file, obtaining the byte ranges
> corresponding to particular tracks should not be problem and is comparable
> to way it is done in the time dimension.

That's interesting and good to know. Curious to see that working.


>> > In case of the latter, I did not experience any problems with both
>> Ogg
>> > and MP4 regarding time and track fragments.
>>
>> So, the client sends a
>> http://example.com/video.ogg?track="track1","track2", then the server
>> resolves that to time ranges, sends back that mapping to the client
>> and the client does the byte range requests? Or does the server just
>> immediately send back the required data, with a newly created header?
>
> Currently, the server sends immediately back the required data. However,
> since our underlying implementation is based on byte range composition, it
> should be relatively easy to send a byte range mapping to the client too.

Out of curiosity: Did you use the headers that are in the current spec
or something earlier?

Cheers,
Silvia.
Received on Wednesday, 17 February 2010 13:01:39 GMT

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