Re: [mediaqueries4] Media queries for multichannel audio ?

Florian, all,

What should be the next steps on this - should I provide more detailed use
cases ? (in email, or is there a wiki ?)

...Mark

On Sat, Mar 23, 2013 at 10:06 AM, Mark Watson <watsonm@netflix.com> wrote:

>
>
> Sent from my iPhone
>
> On Mar 23, 2013, at 6:20 AM, "Florian Rivoal" <florian@rivoal.net> wrote:
>
> > On Wed, 20 Mar 2013 16:03:48 +0100, Mark Watson <watsonm@netflix.com>
> wrote:
> >
> >> Florian, all,
> >>
> >> How do I progress this issue ? Do I need to file a bug ? (where?) Do I
> need to join the WG ?
> >
> >
> > Leaving your other two issues aside for the moment, and focusing on the
> mutichannel part.
> >
> > There is no need to join the WG, raising the issue in this mailing list
> and following up on conversations (as you are doing) is normally enough.
> Once we reach sufficient consensus, or at least understand well enough the
> questions that needs to be answered, we can take it to one of our weekly
> conference calls to try and decide one way or the other.
> >
> > From where I stand, I see a few open questions with your proposal:
> >
> > * Should it be number of channels, or number of speakers?
> > To answer this questions, we would need a variety of use cases to be
> described, to be able to judge which one fits best.
> >
>
> It's the number of output channels, because:
> - you can't know the number of speakers - the audio output may be a
> digital one connected to an A/V receiver or other equipment which is then
> connected to the speakers.
> - some systems use audio processing techniques to simulate surround sound
> without the usual number of speakers - for example soundbars.
>
> Some use-cases, all involving content available in stereo and 5.1,
> provided as alternative <source> elements in an HTML media element:
> - a PC that supports the 5.1 codec, but is outputing the audio over a
> stereo analogue output jack
> - a PC that is outputing the audio over a 5.1 digital audio output
> (S/PDIF, HDMI)
> - a TV that is outputing the audio over internal stereo speakers, with
> only a capability for basic downmixing
> - a TV that is outputing the audio over a 5.1 capable digital audio output
> - a TV with internal signal processing that is capable of simulating
> surround sound from a 5.1 input through less than 6 speakers
>
> > * If number of speakers, can that be reliably detected?
> > I am not an expert on the topic, but it seems to be that the OS (let
> alone the browser) is not necessarily aware of how many physical speakers
> there are.
> >
> > * It seems to me that your main use case for this media query would not
> actually be applying different styles based on the situation, but feed that
> back into javascript, and use it there. If that's the case, I wonder if
> media queries is the best tool to solve the problem.
>
> It's a resource selection problem, which is done today on the media
> element using media queries (the media attribute of the <source> element)
> and could be done in the Media Source case by JavaScript using the
> mediaMatch() function (ensuring that the script approach matches the
> declarative approach).
>
> ...Mark
> >
> >
> > - Florian
> >
>
>
>