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parameter</title></head><body>
<div>At 11:59 -0700 9/04/07, Charles Iliya Krempeaux
wrote:</div>
<blockquote type="cite" cite>Hello,<br>
</blockquote>
<blockquote type="cite" cite>On 4/9/07,<b> Dave Singer</b> <<a
href="mailto:singer@apple.com">singer@apple.com</a>> wrote:<br>
<blockquote>WARNING: I have CC'd the co-authors of the RFC, as I
think they might like to see the discussion, comment on my answers,
and possibly correct me. I also have a question whether there is
a typo in the RFC...</blockquote>
<blockquote><br></blockquote>
<blockquote>* * * * *</blockquote>
<blockquote><br></blockquote>
<blockquote><br></blockquote>
<blockquote>Henry</blockquote>
<blockquote><br></blockquote>
<blockquote>these are all great questions. Let me see how many I
can answer.</blockquote>
<blockquote><br></blockquote>
<blockquote>Overall, the RFC was struggling with the issue that there
is no 'uniform' naming of codecs; the namespace for codecs is
dependent on the container format, so products that do container
conversion have to have tables of code matches. ugh.
That's why the RFC is as it is.</blockquote>
<blockquote><br></blockquote>
<blockquote>The RFC suggests that updated information would be done
with RFCs, which is a little heavy. The RFC as written formally
applies to 3GPP files and 3GPP2 files, but the definitions are
applicable for all ISO-family files.</blockquote>
<blockquote><br></blockquote>
<blockquote>As you'll see below, 3GPP has also defined it for avc1 in
MP4-family containers, but no spec. or registration authority provides
a pointer. We might want to ask IANA whether we could add
something to the MIME registry.</blockquote>
<blockquote><br></blockquote>
<blockquote><br></blockquote>
<blockquote>At 11:37 +0300 8/04/07, Henri Sivonen wrote:<br>
<blockquote type="cite" cite><br>
* Theora video and Vorbis audio in Ogg container.
(application/ogg; .ogg)<br>
* Dirac video and Vorbis audio in Ogg container.
(application/ogg; .ogg)<br>
* Theora video and Vorbis audio in Matroska container.
(video/x-matroska; .mkv)<br>
* Dirac video and Vorbis audio in Matroska container.
(video/x-matroska; .mkv)<br>
</blockquote>
</blockquote>
<blockquote><br></blockquote>
<blockquote>My understanding is that the Ogg container is 'specific'
to these codecs, and therefore the codecs parameter is not needed.
But I am not an Ogg or Matroska expert; perhaps they could chime
in?<br>
</blockquote>
</blockquote>
<blockquote type="cite" cite><br>
No. The containers are independent of the codecs put inside.<br>
<br>
However, whether software, that supports Ogg or Matroska containers
will actually be able to "play" other codecs is another
issue altogether.<br>
</blockquote>
<blockquote type="cite" cite>[...]<br>
</blockquote>
<div><br></div>
<div>so a defined 'codecs' parameter might be prudent, perhaps.
Thanks for the correction.</div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div>David Singer<br>
Apple Computer/QuickTime</div>
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