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Re: [AVT] Re: Comments on draft-freed-media-types-reg-01.txt



Hi Ned,

We need to resolve this. And I do not consider it resolved as long as it is not sufficient motivated and way of handling the already approved specifications is indicated.

I can understand the need for caution if registering different parameters for different applicability. How does one clarify what is acceptable, and what is not? Thus please answer Colin's questions below in attempt to define some borders.

Is your point that if you need a different piece of software to correctly handle the data, then it is another type. Like the fact that you need to have a handler of RTP timestamp that sorts frame correctly for AMR RTP payload format, while the file format only needs to be able to read the frames in sequence to get the order?

Secondly how does we handle the already registered types? They are almost impossible to change due to the deployed base of at least some of the types. The file format for AMR is deployed in a couple of millions mobile phones that support MMS. Do we only leave them in as anomalies in the system?


Cheers

Magnus


Colin Perkins wrote:

File header/magic number != framing in my book.


So, what do you mean by framing? In the examples I'm quoting, the media
data format is bitwise identical in both cases.  The difference is that
it's framed in a file (and hence has a file header) rather than a series
of RTP packets (and hence has an RTP header); once you strip the framing
there is no difference in format.

And this will be my last message on this topic.


Which doesn't resolve the conflict between draft-freed-media-types-reg
-01.txt and existing practice. Much as you may dislike it, there are two
proposed standards (RFC 3267 and 3558) which register formats in the way
I describe. The change you propose is problematic for a significant user
community, which has previously registered these types in good faith, according to IETF procedures.


Colin



--

Magnus Westerlund

Multimedia Technologies, Ericsson Research EAB/TVA/A
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