Re: [MMUSIC] Simulcast worries: Fallback in the a=rid language

Harald Alvestrand <harald@alvestrand.no> Wed, 21 October 2015 20:27 UTC

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To: Martin Thomson <martin.thomson@gmail.com>
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From: Harald Alvestrand <harald@alvestrand.no>
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Date: Wed, 21 Oct 2015 22:27:16 +0200
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Subject: Re: [MMUSIC] Simulcast worries: Fallback in the a=rid language
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On 10/21/2015 08:35 PM, Martin Thomson wrote:
> On 21 October 2015 at 06:57, Harald Alvestrand <harald@alvestrand.no> wrote:
>> 1 - Toss all RIDs that it cannot parse fully
> This.
>
> If you were able to handle options that didn't limit goats, then you
> can add an alternative profile that doesn't include any max-goats
> constraints:
>
> a=rid:1 recv max-goats=47;max-fr=50
> a=rid:2 recv max-goats=22;max-fr=20
> a=rid:3 send max-goats=44;max-fr=20
> a=rid:4 send max-goats=22;max-fr=10
> a=rid:5 recv max-fr=10
> a=rid:6 recv max-fr=5
> a=rid:7 send max-fr=10
> a=rid:8 send max-fr=5
> a=simulcast: send rid=3;4,7;8 recv rid=1;2,5;6
>
> (I've probably gotten the syntax off here, but I hope that this is clear enough.
But to a receiver that understands max-goats, this is a profile that
says "send me 4 simulcast streams if you feel like it", not "send me
either these two or those two".

This may be harmless, but it may be surprising.


-- 
Surveillance is pervasive. Go Dark.