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Re: Spec question: Using settings dictionaries instead of MediaConstraints ([ACTION-50])

From: Justin Uberti <juberti@google.com>
Date: Mon, 18 Jun 2012 21:48:06 -0400
Message-ID: <CAOJ7v-3oTWxMhN362bmBiy=uBuXkma7mdb5R7Lma34TPNE_CLg@mail.gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
Cc: Adam Bergkvist <adam.bergkvist@ericsson.com>, "public-webrtc@w3.org" <public-webrtc@w3.org>
On Mon, Jun 18, 2012 at 7:53 PM, Eric Rescorla <ekr@rtfm.com> wrote:

> On Mon, Jun 18, 2012 at 5:13 AM, Adam Bergkvist
> <adam.bergkvist@ericsson.com> wrote:
> > On 2012-06-15 21:28, Justin Uberti wrote:
> >>
> >> At the interim, it was indicated that using MediaConstraints for
> >> non-media PeerConnection methods was probably not the right fit, one
> >> reason being that most options were only relevant for a specific method,
> >> and it would be good to make it clear which options should be passed to
> >> which methods.
> >>
> >> Therefore I propose that we define other settings dictionaries, similar
> >> to MediaConstraints, but named specifically for the methods in which
> >> they will be used.
>
> Generally, I like this approach. Some (hopefully easy) nits below.
>
> >> This results in new dictionaries IceOptions and
> >> SessionDescriptionOptions, with values as shown below:
> >>
> >> IceOptions.AllowedCandidates = ("none", "relay", "all) // "all", if not
> >> specified
> >>
> >> SessionDescriptionOptions.IncludeAudio = true/false // forces m=audio
> >> line to be included
> >> SessionDescriptionOptions.IncludeVideo = true/false // forces m=video
> >> line to be included
>
> By "forces" you mean "even if I don't include a video stream"?
> That's what I'm taking from Adam's comment.
>

Correct.


> What happens if I AddStream() a video stream  but set this to
> false?
>

One of the following:
1. The setting is ignored.
2. The stream is ignored.
3. An exception is thrown.


> Maybe it would make more sense to have this *only* control
> generating a recv-type media stream and have addstream
> control only a send-type.
>

This controls adding a m= line in the offer or answer, which is needed if
we want to send or receive. The original intent was to make the meaning of
this setting to be "include a m=video line if one doesn't already exist",
which would be essentially #1 above.

Or we could be strict and do #3.


>
>
> >> SessionDescriptionOptions.UseVoiceActivityDetection = true/false //
> >> includes CN codecs if true
>
>
> >> SessionDescriptionOptions.RestartIce = true/false // generates offer
> >> with new ufrag/pwd
> >> SessionDescriptionOptions.GetCapabilities = true/false // generates
> >> "capabilities" offer
> >>
> >> These fit into the existing API on the createOffer/Answer and updateIce
> >> methods:
> >>
>
> Hmm... So I can't update my iceOptions when I do createAnswer?
> If I want to convert from relay only I have to do updateIce?
>

Yes - because IceOptions affect more than the SDP - they also affect the
candidates used by the ICEAgent for checks.

>
>
> >> [Constructor (IceServers configuration, optional IceOptions iceOptions)]
> >> interface PeerConnection {
> >>    void createOffer(SessionDescriptionCallback
> >> successCallback, optional PeerConnectionErrorCallback failureCallback,
> >> optional SessionDescriptionOptions options);
> >>    void createAnswer(SessionDescriptionCallback
> >> successCallback, optional PeerConnectionErrorCallback failureCallback,
> >> optional SessionDescriptionOptions options);
> >>   ...
> >>
> >>    void updateIce(optionalIceServersconfiguration,
> >> optional IceOptions options);
> >>
> >>
> >> Does this look reasonable?
>
> -Ekr
>
Received on Tuesday, 19 June 2012 01:48:56 UTC

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