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Re: Media Capture and Streams Last Call review

From: Joe Berkovitz <joe@noteflight.com>
Date: Tue, 12 May 2015 09:52:58 -0400
Message-ID: <CA+ojG-bA2ezPyK8tk2q1FQ9SDWSKH6AruTgS-r3EGiLVzXgM7A@mail.gmail.com>
To: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
Cc: Audio Working Group <public-audio@w3.org>
Thanks Stefan.

The capture of my comments seems fine and I've subscribed to the list as
you suggested.

...Joe

On Tue, May 12, 2015 at 2:57 AM, Stefan Håkansson LK <
stefan.lk.hakansson@ericsson.com> wrote:

> On 30/04/15 15:37, Joe Berkovitz wrote:
> > 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?
>
> Hi Joe,
>
> all LC comments are gathered at
>
> https://www.w3.org/2006/02/lc-comments-tracker/47318/WD-mediacapture-streams-20150414/
> - so it could make sense to check that your comments are captured there.
>
> We are planning for a Media Capture TF call later in May to discuss how
> to deal with the comments, and the chairs plan to send a proposal to the
> list before the call. Likely there will be some comments that are easy
> to deal with, and some that require more discussion.
>
> I think that for now, the best thing for the Audio WG would be to
> (assign someone to) monitor the public-media-capture list. It should be
> doable, the amount of traffic is not that big.
>
> Best regards,
> Stefan
>
> >
> > Best regards,
> >
> > ...Joe
> >
> >
> > On Wed, Apr 22, 2015 at 1:24 AM, Stefan Håkansson LK
> > <stefan.lk.hakansson@ericsson.com
> > <mailto: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 <tel:%2B1%20978%20314%206271>
> >      > www.noteflight.com <http://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>
> >      > <mailto: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>
> >     <mailto: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 <tel:%2B1%20978%20314%206271>
> >      > www.noteflight.com <http://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 <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"
Received on Tuesday, 12 May 2015 13:53:26 UTC

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