Re: Media Capture and Streams Last Call review

Thank you so much, Stefan.

What is the best way for members of the Audio WG to track the progress of
this issue within the Media Capture TF?

Best regards,

...Joe


On Wed, Apr 22, 2015 at 1:24 AM, Stefan Håkansson LK <
stefan.lk.hakansson@ericsson.com> wrote:

> Many thanks for providing valuable feedback!
>
> On 21/04/15 20:59, Joe Berkovitz wrote:
> > Hello Stefan,
> >
> >
> > Thank you for your recent solicitation of feedback to on the Media
> > Capture and Streams API, which I passed to the Web Audio Working Group.
> >
> >
> > The Web Audio WG so far has identified one key item that we would like
> > to see addressed. The MediaDeviceInfo result from enumerateDevices()
> > (
> http://www.w3.org/TR/2015/WD-mediacapture-streams-20150414/#idl-def-MediaDeviceInfo
> )
> > lacks information that is typically available in the underlying OS
> > implementations that we think would be very helpful for implementations:
> >
> > __ __
> >
> > __·__Channel count and configuration (Mono, Stereo, 5.1, 7.1, etc…)____
> >
> > __·__Physical Output (Headphone, Speaker, HDMI, …)____
> >
> > __·__Latency (this matters a lot for gaming -- it will be very low for
> > on-board hardware, perhaps quite high for wireless audio bridging like
> > Apple TV)____
> >
> > __·__Output capabilities (bitstream passthrough vs PCM – relevant in
> > digital media adapter cases (Chromecast, etc))____
> >
> >
> > It is perhaps sufficient from a user interface point of view to have a
> > string to display, but for a program to be able to either adapt to the
> > user selection or to guide and default the user selection, the above are
> > pretty important characteristics, at least in some use cases. Many if
> > not most of the host OSes that user agents run on expose these sorts of
> > output device characteristics. ____
> >
> >
> > Aside from the difficulty with enumerating devices, there is also
> > perhaps a need to make it possible for applications to query the set of
> > available devices with respect to the above charateristics.
> > MediaTrackConstraints and MediaTrackSettings do not currently  include
> > constraint attributes that map to items in the above list. And even if
> > they do, arriving at a practical goodness-of-fit metric that can be
> > generalized across a spectrum of audio apps may be difficult.
> >
> >
> > The same concerns apply to the set of input devices.__
> >
> > __ __
> >
> > Please let us know if this issue makes sense to the group and can be
> > addressed within the timeframe of the coming run-up to a Last Call WD.
> > We'd be happy to arrange some sort of inter-WG call to try to make
> > progress on this together.
> >
> >
> > Thank you!
> >
> >
> > Best regards,
> >
> >
> > Joe Berkovitz
> >
> > co-chair Web Audio WG
> >
> >
> > *Noteflight LLC*
> > Boston, Mass.
> > phone: +1 978 314 6271
> > www.noteflight.com <http://www.noteflight.com/>
> > "Your music, everywhere"
> >
> > On Wed, Apr 15, 2015 at 1:31 AM, Stefan Håkansson LK
> > <stefan.lk.hakansson@ericsson.com
> > <mailto:stefan.lk.hakansson@ericsson.com>> wrote:
> >
> >     The WebRTC and Device APIs Working Groups request feedback on the
> Last
> >     Call Working Draft of Media Capture and Streams, a JavaScript API
> that
> >     enables access to cameras and microphones from Web browsers as well
> as
> >     control of the use of the data generated (e.g. rendering what a
> camera
> >     captures in a html video element):
> >     http://www.w3.org/TR/2015/WD-mediacapture-streams-20150414/
> >
> >     The groups have identified the following other W3C Working Groups as
> >     likely sources of feedback:
> >
> >     - HTML Working Group, especially the HTML Media Task Force, as our
> API
> >     extends the HTMLMediaElement interface and defines a new type of
> media
> >     input via MediaStream
> >
> >     - WebApps Working Group, especially on the overall usage of Web IDL
> and
> >     the definition of error handling
> >     Audio Working Group, as the Web Audio API builds upon the MediaStream
> >     interface
> >
> >     - WAI Protocol and Formats Working Group, especially on the impact of
> >     the user consent dialog and the applicability of the indicators of
> >     device usage in assistive tools
> >
> >     - Web and TV Interest Group, as the manipulation of media input can
> be
> >     relevant to some of their use cases (e.g. glass to glass)
> >
> >     - Web App Security Working Group, especially on our links between
> >     secured origins and persistent permissions, and our current policy
> with
> >     regard to handling access to this "powerful feature"
> >
> >     - Web Security Interest Group, especially on our security
> considerations
> >     Privacy Interest Group, as access to camera and microphone has strong
> >     privacy implications
> >
> >     - Technical Architecture Group, for an overall review of the API,
> >     especially the introduction of the concept of a IANA registry-based
> >     constraints system, the use of promises, and our handling of
> persistent
> >     permissions
> >
> >     We naturally also welcome feedback from any other reviewers.
> >
> >     The end of last call review for this specification is set to May 15
> >     2015; should that deadline prove difficult to meet, please get in
> touch
> >     so that we can determine a new deadline for your group.
> >
> >     As indicated in the document, comments should be sent to the
> >     public-media-capture@w3.org <mailto:public-media-capture@w3.org>
> >     mailing list.
> >
> >     Thanks,
> >
> >     Frederick Hirsch, Device APIs Working Group Chair,
> >     Harald Alvestrand and Stefan Hakansson, WebRTC Working Group Chairs
> and
> >     Media Capture Task Force Chairs
> >
> >
> >
> >
> > --
> > .            .       .    .  . ...Joe
> >
> > *Joe Berkovitz*
> > President
> >
> > *Noteflight LLC*
> > Boston, Mass.
> > phone: +1 978 314 6271
> > www.noteflight.com <http://www.noteflight.com>
> > "Your music, everywhere"
>
>


-- 
.            .       .    .  . ...Joe

*Joe Berkovitz*
President

*Noteflight LLC*
49R Day Street / Somerville, MA 02144 / USA
phone: +1 978 314 6271
www.noteflight.com
"Your music, everywhere"