RE: Audio device selection

De : Harald Alvestrand [mailto:harald@alvestrand.no]
Envoyé : vendredi 8 février 2013 22:28
À : CAZEAUX Stephane OLNC/OLPS
Cc : public-webrtc@w3.org
Objet : Re: Audio device selection

On 02/08/2013 08:53 PM, stephane.cazeaux@orange.com<mailto:stephane.cazeaux@orange.com> wrote:
Hi all

I am wondering if something is not missing in audio device selection for some communication case.

Well, first off, this is a media capture matter, so should go to public-media-capture@w3.org<mailto:public-media-capture@w3.org>....
[SC] I am not sure of that. Here I am dealing with how is rendered the audio received from the network.


Regarding to audio device selection, the media capture scenario document (https://dvcs.w3.org/hg/dap/raw-file/tip/media-stream-capture/scenarios.html) talks of the case where the user selects between a microphone device plugged to the audio jack, or the microphone of a webcam. But there is another common case: the user has a microphone in the audio jack and a usb headset (speaker+microphone). To me, in this case:

-          When the user selects the microphone device in the audio jack, he will most likely want to hear the remote party in the speakers of the computer

-          When the user selects the USB headset device, he will most likely want to hear the remote party in the headset

"Most likely" isn't the same as "always".
[SC] I did not say « always »

I regularly use a headset with a broken microphone; in those cases, I need to select the camera microphone (because that's the one that gives the best sound).
[SC] Well, on my side, I am always using usb devices, and expect to be able to switch between a usb headset and usb speaker phone

I think it is better that the API present those as independent choices.
[SC] That's exactly what my « most likely » meant: let the user choose. But I don't see in the specification how the choice will be given to the user.




But with some tests based on Chrome 24, the audio is always played through the OS default audio device, even if I select a usb headset as audio capture device (which is of course not the OS default device).
AFAIK, this is explained by the fact that on one hand the media capture API enables the selection of the capture device only. On the other hand, audio HTML tag uses the default rendering device of the system. I could not find any document talking of audio rendering device selection.

Chrome 24 doesn't have input microphone selection yet.

Please don't judge the specification by the state of the implementation.
[SC] That was not my intent, but just an illustration.




Any thought about this? Did I miss something?


Stéphane.