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[MEDIA_PIPELINE_TF] minutes - 29 March 2012

From: Kazuyuki Ashimura <ashimura@w3.org>
Date: Fri, 30 Mar 2012 01:09:23 +0900
Message-ID: <4F748933.1040209@w3.org>
To: public-web-and-tv@w3.org
available at:
  http://www.w3.org/2012/03/29-webtv-minutes.html

also as text below.

Thanks a lot for taking these minutes, Franck!

Kazuyuki

---
    [1]W3C

       [1] http://www.w3.org/

                                - DRAFT -

                 Media Pipeline Task Force Teleconference

29 Mar 2012

    [2]Agenda

       [2] 
http://www.w3.org/2011/webtv/wiki/MPTF/Agenda_Telco_29th_March_2012

    See also: [3]IRC log

       [3] http://www.w3.org/2012/03/29-webtv-irc

Attendees

    Present
           Glenn, Clarke, Dave, Philipp, Joe, Duncan, Franck,
           Kevin, Jason, Kazuyuki, Mark_Vickers, Juhani(?),
           Mark_Watson, Paul

    Regrets
    Chair
           Clarke

    Scribe
           franck

Contents

      * [4]Topics
          1. [5]Encrypted Media TF of the HTML WG
          2. [6]adaptive bit rate proposal (Media Source extension)
      * [7]Summary of Action Items
      __________________________________________________________

    <Clarke> ABR proposal:
    [8]http://html5-mediasource-api.googlecode.com/svn/trunk/draft-
    spec/mediasource-draft-spec.html

       [8] 
http://html5-mediasource-api.googlecode.com/svn/trunk/draft-spec/mediasource-draft-spec.html

    <Mark_Vickers> It would be good to put the GoToMeeting info on
    the Logistics page.

Encrypted Media TF of the HTML WG

    <glenn> i will ask at the upcoming HTML WG meeting in an hour

    <kaz> [9]HTML public list discussion

       [9] 
http://lists.w3.org/Archives/Public/public-html/2012Mar/thread.html#msg275

    <inserted> scribenick: franck

adaptive bit rate proposal (Media Source extension)

    <kaz> [10]proposal v0.4

      [10] 
http://html5-mediasource-api.googlecode.com/svn/tags/0.4/draft-spec/mediasource-draft-spec.html

    mw: discussing segment switching, required to be on SAP

    yes

    Dicussing requirement 3:

    Any challenges with trick play?

    CS: Req 4: using canPlayType or other means...
    ... improvement for interop if canPlayType could provide more
    info

    <kaz> i|Discussing requirement 3:|->
    [11]http://www.w3.org/2011/webtv/wiki/MPTF#Adaptive_Bit-Rate_Co
    ntrol_in_Script_.28model_3.29 ABR Requirements|

      [11] 
http://www.w3.org/2011/webtv/wiki/MPTF#Adaptive_Bit-Rate_Control_in_Script_.28model_3.29

    MW: mimeType provide info on codecs
    ... 2nd would be info on container format in use
    ... If your player support these both types, should be OK
    ... examples on different mp4 boxes organization: should it be
    exposed?

    MV: could MPEG-2 TS can be used ?

    CS: next requirement 5 on no advantage for a method aver
    another
    ... combination of codecs/file formats

    MW: discussing segment switching between Apple HLS and DASH
    segments

    CS: people implementing HLS put the burden on the client, would
    be good to have feedback from HLS people

    Req 6: "must work with open source browsers"

    CS: make sure that open source browser can use this method to
    do ABR
    ... if we focus on unencrypted content, try to keep content
    protection elsewhere, req 6 should be fulfilled ?
    ... Mark, any opinion ?

    <kaz> ACTION: Stevens to ping D. Singer on requirement 5
    [recorded in
    [12]http://www.w3.org/2012/03/29-webtv-minutes.html#action02]

    <trackbot> Created ACTION-97 - Ping D. Singer on requirement 5
    [on Clarke Stevens - due 2012-04-05].

    MW: ask Chrome guys

    CS: content protection: is there anything that would prevent
    open source browser to implement ABR with a proprietary
    decryption part ?

    MW: need to make sure that jscript will be able to access
    segment info and timing info
    ... ...independently from how it has been encrypted

    CS: next requirement 7: "ABR media must be useable in HTML5"
    ... no specific comment
    ... Req 8: (linked to Req4), content must be identifiable

    MW: HLS/DASH, which profile, or whatever, would be handled by
    the script, thus does not apply to media source extension

    CS: should we change wording for this req?
    ... ... and review next time
    ... Req 9: identifiable parameters
    ... pass info through mime type and mime parameters: is it
    sufficient?

    MW: seems yes

    CS: Req 10: error reporting
    ... need for new errors ?

    MW: none provided yet

    CS: any errors needed to communicate back to the media element?

    MW: talking about browser doing the fetching itself , instead
    of XHR
    ... some interactions there, maybe with errors ?

    CS: We'll assume it's OK and somebody to speak if not

    MV: case where splicing ad into the media: ?

    MW: use another media element to render the ad

    MV: add this use case as a requirement: how to properly handle
    this (ad insertion impact on presentation timeline)

    CS: Please provide text on the wiki

    MV: OK

    MW: you would need some changes in the API to perform this use
    case

    MV: look at it carefully

    CS: Useful to have best practises ?
    ... any additional reqs?
    ... open item: document to provide to HTML TF, should be ready
    in 1-2 calls

    <kaz> [ adjourned ]

    <Clarke> Thanks Franck

    <kaz> thanks, franck!

    bye!

Summary of Action Items

    [NEW] ACTION: Stevens to ping D. Singer on requirement 5
    [recorded in
    [13]http://www.w3.org/2012/03/29-webtv-minutes.html#action01]

    [End of minutes]
      __________________________________________________________


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Received on Thursday, 29 March 2012 16:10:38 UTC

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