Re: [AVT] Inquiry about RFC 4629 (optional parameters in SDP)

[Randell Jesup <rjesup at wgate.com>]

"Even, Roni" <roni.even at polycom.co.il> writes:
>Those annexes can be signaled as part of profiles in annex X of H.263.
>Annex X is not proprietary; you can use H263-2000 with profile and levels.
>Specific bodies like 3GPP recommended specific annex X profiles.

Ah.  Ok, that makes more sense; when you said "profiles" I thought you
meant profiles in the SDP sense (like RTP/AVP).

>I do not think that anyone will develop a new product using a specific
>annex not in the list or not part of a profile. There is H.264 today.

True, though H.264 uses a lot more computational resources; *if* you have
the bits to throw at it, 263+ may let you get higher framerates or
resolutions than 264 on a given platform.

>In H.323 we had all the annexes with all the options.
>Since in IETF for a standard you must have only parameters that are used
>we asked on the list if people are using other annexes which were not in
>RFC 4629.

It probably doesn't matter, but I'm not clear about "for a standard you
must have only parameters that are used" and how exactly it applies here.
Most IETF standards predate their usage, so that doesn't make sense.

-- 
Randell Jesup, Worldgate (developers of the Ojo videophone), ex-Amiga OS team
rjesup at wgate.com
"The fetters imposed on liberty at home have ever been forged out of the weapons
provided for defence against real, pretended, or imaginary dangers from abroad."
		- James Madison, 4th US president (1751-1836)


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