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Re: [call for comments] ma:compression vs. ma:coding vs. ma:encoding

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Wed, 28 Apr 2010 23:28:50 +1000
Message-ID: <n2v2c0e02831004280628m452f4a13x9868e3c54c84a219@mail.gmail.com>
To: "Christian Timmerer (ITEC)" <christian.timmerer@itec.uni-klu.ac.at>
Cc: "Evain, Jean-Pierre" <evain@ebu.ch>, Daniel Park <soohongp@gmail.com>, "public-media-annotation@w3.org" <public-media-annotation@w3.org>
Hi Christian,

On Wed, Apr 28, 2010 at 11:18 PM, Christian Timmerer (ITEC) <
christian.timmerer@itec.uni-klu.ac.at> wrote:

> On Apr 28, 2010, at 3:00 PM, Silvia Pfeiffer wrote:
> They are not really URIs, but URNs that were defined by MPEG. Also, I would
> suggest to extend the document with the codecs parameter for the MIME types
> which have been standardised for some of the existing MPEG MIME types (and
> are actually in use in HTML5).
> Well, yes, please provide me a list and I'm happy to integrate. However,
> this document just maintains MPEG codecs ;-)

Some are listed here: http://www.mp4ra.org/codecs.html

Also, the following examples are given here
http://www.ietf.org/rfc/rfc4281.txt :

   Content-Type: video/3gpp2; codecs="sevc, s263"
       (EVRC audio plus H.263 video)
   Content-Type: audio/3gpp; codecs=samr
       (AMR audio)
   Content-Type: video/3gpp; codecs="s263, samr"
       (H.263 video plus AMR audio)
   Content-Type: audio/3gpp2; codecs=mp4a.E1
       (13k audio)
   Content-Type: video/3gpp2; codecs="mp4v.20.9, mp4a.E1"

(MPEG-4 Visual Simple Profile Level 0 plus 13K voice)

I can see that you would want more information on the format than just
> encapsulation format and codecs (which is typically what the MIME types give
> you). You also want profiles. Maybe then ma:encoding_profiles is the right
> word?
> Don't get me wrong, I just wanted to point out, that this document exists
> and maybe you find it useful for your discussion.

Oh, this question was directed not at you, but at the complete email thread,
so don't worry.

Received on Wednesday, 28 April 2010 13:29:47 UTC

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