Re: [rtcweb] Proposed Plan for Usage of SDP and RTP - Lower level API minus SDP

Silvia Pfeiffer <silviapfeiffer1@gmail.com> Fri, 08 March 2013 02:56 UTC

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From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Fri, 8 Mar 2013 13:56:16 +1100
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To: "Timothy B. Terriberry" <tterriberry@mozilla.com>
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Subject: Re: [rtcweb] Proposed Plan for Usage of SDP and RTP - Lower level API minus SDP
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On Fri, Mar 8, 2013 at 11:28 AM, Timothy B. Terriberry <
tterriberry@mozilla.com> wrote:

> Silvia Pfeiffer wrote:
>
>> For example: the programmer wants to say - I want to get this video
>> resolution, this audio bitrate & channels, I want to use this camera and
>> this microphone for this call. Having to manipulate SDP directly for
>> this is a programmer's nightmare.
>>
>
> I would like to point out that the currently proposed W3C APIs do not
> require (or even allow) SDP manipulation for _any_ of this, with the
> possible exception of audio bitrate (which, as we've long discussed, should
> actually be adapted in real-time based on available bandwidth as determined
> by congestion control, with some app-provided way to set priorities that
> will _not_ be based on SDP... the number in SDP merely defines the limits
> of what's possible).


Is there any way for the Web developer to influence the negotiation of,
say, the video resolution? For example, if the video is displayed in a
160x120 video element, then it makes no sense to receive anything larger
than that resolution. I was under the impression that this would have to be
done through manipulating SDP?

Silvia.