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Re: Media Capture and Streams Last Call review

From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
Date: Fri, 1 May 2015 06:25:12 +0000
To: Joe Berkovitz <joe@noteflight.com>, Dominique Hazael-Massieux <dom@w3.org>
CC: Audio Working Group <public-audio@w3.org>
Message-ID: <1447FA0C20ED5147A1AA0EF02890A64B1D1F85D0@ESESSMB209.ericsson.se>
Hi Joe,

we're employing a tool to keep track of last call comments, and Dom is 
the expert!

Dom, could you help me out here?

Best regards,
Stefan

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?
>
> 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"
Received on Friday, 1 May 2015 06:27:00 UTC

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