[MEDIA_PIPELINE_TF] minutes - 10 May 2012

available at:
  http://www.w3.org/2012/05/10-webtv-minutes.html

also as text below.

Thanks a lot for taking minutes, Kevin!

Kazuyuki

---
    [1]W3C

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

                                - DRAFT -

                 Media Pipeline Task Force Teleconference

10 May 2012

    [2]Agenda

       [2] http://www.w3.org/2011/webtv/wiki/MPTF/Agenda_Telco_10th_May_2012

    See also: [3]IRC log

       [3] http://www.w3.org/2012/05/10-webtv-irc

Attendees

    Present
           clarke, kaz, bryan, bob, joe, kevin, Juhani, eric, john,
           ??P32, 443-030-40xxxx, 425-214-xxxx, 858-735-xxxx,
           617-761-xxxx, 415-832-xxxx, 617-761-xxxx, ??P58,
           206-218-xxxx, 425-882-xxxx, 617-761-xxxx

    Regrets
    Chair
           Clarke

    Scribe
           kstreeter, kaz

Contents

      * [4]Topics
          1. [5]face to face last week
          2. [6]WebPerf
          3. [7]bug tracking
          4. [8]requirements documents
      * [9]Summary of Action Items
      __________________________________________________________

    <nisc> this passcode is not valid ? :(

    <inserted> scribenick: kstreeter

face to face last week

    Bob: Summary of last week:

    aaron presented the media source proposal

    [mark?] presented the encrypted media proposal

    discussed the formation of a media task force

    it was decided to keep the work in the group

    discussion on whether to keep the two proposals together

    John: none of the acrimonious comments on the enc media
    proposal really came up in the f2f

    there is a transition happening between HTML5 and HTML next

    Aaron: there is a sense that the HTML5 ship has sailed, and
    there is an opp for cooperation moving forwad in the HTML WG

    s/fowad/forward/

    Aaron: Paul Cotton indicated that he would moderate the calls
    regarding the media proposals

    John: Google presented a couple of good demos, are these
    available online?

    Aaron: yes, online will find a link

WebPerf

    some of the metrics being discussed by webperf could be
    utilized by the media source elements

    this group should familiarize themselves; we will discuss next
    week

bug tracking

    many messages this week, means work is progressing

    bug11492

    no new bugs

requirements documents

    <Clarke> ABR Requirements:
    [10]http://dvcs.w3.org/hg/webtv/raw-file/tip/mpreq/MPTF-ADB-Req
    uirements.html

      [10] 
http://dvcs.w3.org/hg/webtv/raw-file/tip/mpreq/MPTF-ADB-Requirements.html

    updated the terminology

    group should review the terminology changes as well as the reqs

    added use cases

    reviewing use case 5.1

    the terminology for ABR "media" or ABR "system" is ill-defined,
    we could clarify this

    reviewing use case 5.2 U2

    Kevin: could add the need to handle trick modes across time
    discontinuities

    Joe: content protection can also impact trick modes, we should
    call that out as well

    Aaron: what are the expectations around consistency between
    different systems?

    Clarke: the primary thing is that from a user perspective
    dealing with trick modes in ABR should be similar to that of
    non-ABR content

    Aaron: some adaptive systems might handle trick modes slightly
    differently, for example switch to lower bitrate

    Bob: even in non-adaptive there are often differences on how
    different media handle trick play
    ... different user agents will often do trick modes differently
    to enhance user experience

    Kevin: perhaps we could define this more as a req for the
    mechanisms to initiate trick plays, rather than the end
    experience

    Bob: could express this in terms of the media element
    attributes that manage trick modes
    ... this could be more succinct

    reviewing use case 5.3 U3. Search Adaptive Bit Rate Content

    Aaron: we should use "seek" rather than "search"

    <inserted> scribenick: kaz

    Clarke: U5. Continuous Adaptive Bit Rate Content
    ... time reference?

    bob: who made that comment?

    kstreeter: kevin from Adobe

    bob: we had some discussion before
    ... are you aware how systems today handle that?
    ... what should for adaptive streaming?

    kstreeter: not aware
    ... I imagine system like Tivo should handle this

    bob: ok

    <nisc> kaz, who is here

    <nisc> kaz, who is here?

    <nisc> er

    <nisc> sorry kaz ;-)

    bob: granularity of time

    Clarke: I guess we could leave it in the requirements, and
    reconsider it later
    ... any other comments for the UC 5?

    (nothing)

    <inserted> scribenick: kstreeter

    reviewing use case 5.6 U6. Timed Tracks and Adaptive Bit Rate
    Content

    Clarke: this is related to the time base requirements

    DASH supports this in the MPD

    Bob: this might boil down to that the implementation must
    support timed text tracks if present

    Aaron: we are going to support inline text tracks

    Kevin: how would this work with external caption file?

    Aaron: yes, you would just use the existing track mechanism
    ... since this is built on existing HTML5, i don't think we
    need to call this out specifically as a requirement

    Clarke: given the above requirements on timeline, this use case
    might not be required

    Aaron: this req does allow a timed text track to be merged into
    content that did not already have one
    ... even if this is redundant timed text is important it is
    worth leaving in

    next week we will talk about the enc content doc

    Aaron: link points to old document

    <Clarke> Thanks for scribing, Kevin

    <kaz> [ adjourned ]

Summary of Action Items

    [End of minutes]

Received on Thursday, 10 May 2012 16:06:27 UTC