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Re: User media constraint: peerIdentity

From: Timothy B. Terriberry <tterriberry@mozilla.com>
Date: Fri, 26 Oct 2012 05:58:28 -0700
Message-ID: <508A88F4.4050806@mozilla.com>
To: public-webrtc@w3.org
Harald Alvestrand wrote:
>> The bigger problem, to my mind, is that it is now impossible to
>> implement a level meter for the audio, so that people can check their
>> mic. We can still provide one in browser chrome in gUM, but not after
>> permission has been granted.
>>
> yes, it's now impossible to get an audio volume meter by channeling the
> audio into the WebAudio API.
>
> If we implement an "audio volume" statistic via the stats API, which has
> been suggested, there is an alternate path; I don't think statistics are
> prohibited for tainted media.

I was thinking more along the lines of providing an HTMLLevelMeter 
element, which would have the benefit of also being useful to developers 
who don't want to go through the difficulty of using the WebAudio API to 
compute mic levels manually. Though I'd be happy to delay such a thing 
until "version 2".

The difficulty with exposing this via statistics is that now you've 
created a side-channel leaking information about the tainted streams 
with, I expect, roughly as much information about them as the much-hyped 
VBR information leak.
Received on Friday, 26 October 2012 12:58:56 UTC

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