W3C home > Mailing lists > Public > public-media-fragment@w3.org > May 2009

minutes of 2009-05-13 teleconference

From: RaphaŽl Troncy <Raphael.Troncy@cwi.nl>
Date: Wed, 13 May 2009 16:26:58 +0200
Message-ID: <4A0AD8B2.3090201@cwi.nl>
To: Media Fragment <public-media-fragment@w3.org>
[re-sent with the correct title]


The minutes of today's telecon are available for review at
http://www.w3.org/2009/05/13-mediafrag-minutes.html (and in text format
below). Thanks Guillaume for the scribbing.

We have just given 1 new action:
  * ACTION-79: Michael to summarise the options for 4xx status code for
empty TC0002-0007 in a Wiki page

and created 1 new issue (that I have further edited):
  * Should we have the media type inside the Test Cases?,

       [1] http://www.w3.org/
                                - DRAFT -
              Media Fragments Working Group Teleconference
13 May 2009
    See also: [3]IRC log
       [3] http://www.w3.org/2009/05/13-mediafrag-irc

           Silvia, Michael, Raphael, Gui, Conrad
           Yves, Erik, Davy


      * [4]Topics
          1. [5]ADMIN, next conference
          2. [6]UC & Requirements
          3. [7]UA Server HTTP Communication
          4. [8]UA MF Resolution and Processing
          5. [9]TEST CASES
      * [10]Summary of Action Items

    <trackbot> Date: 13 May 2009

    <Gui> yes

    <raphael> Scribe: Guillaume

    <raphael> Scribenick: yes

    <mhausenblas> Scribenick: Gui

ADMIN, next conference

    <raphael> Minutes:

      [11] http://www.w3.org/2009/04/29-mediafrag-minutes.html

    <raphael> +1

    <mhausenblas> +1

    Accepting minutes

    <silvia> +1

    Ok, minutes of the 29 April 2009 telecom accepted

    <raphael> Summary: unlikely that Conrad, Silvia and Guillaume can
    make the Amsterdam meeting

    <raphael> ... easier for Europeans (Michael, Jack, Raphael, what
    about Yves?)

UC & Requirements

    The working draft has been published

    All actions arel ongoing

    TOPIC UA Server HTTP Communication

UA Server HTTP Communication

    Conrad will discuss this at the next teleconf

    We need to start capturing what we recommend regarding the use of
    "?" and "#"

    Silvia is getting inputs from the HTML5 mailing-list, any specific
    information that's relevant we should look at? Silvia and Conrad
    please keep track.

    <raphael> Raphael: in the next iteration of the document, we should
    clearly clarify the role of '#' and '?'

    Further discussions about the MF syntax giving absolute times
    mechanism. It is a big requirement. Silvia to continue discuss with

UA MF Resolution and Processing



    Michael would like to take us through the document at some point.

    In the sequence of things, two things needs to be explained :

    the template of HTTP headers



    <silvia> [14]http://www.ietf.org/rfc/rfc2326.txt <- rtsp spec

      [14] http://www.ietf.org/rfc/rfc2326.txt

    [15]http://www.w3.org/2008/WebVideo/Fragments/wiki/Image:Rtsp.jpg <-
    synchronise this picture with more details with the one for http

      [15] http://www.w3.org/2008/WebVideo/Fragments/wiki/Image:Rtsp.jpg

    <mhausenblas> thanks silvia

    <silvia> :)


    Discussing the issues raised on the mailing list

    e.g. t=10,

    Is it good syntax or not?

    Do we need to specify the media type as well for each test case?

    1. the way to express the media type in the fragment syntax (only
    the server would need to know)

    2. Write the media type inside the Test case results

    (We need this data to be able to report on the test cases)

    <raphael> trackbot, status

    ISSUE: Should we have the media type inside the Test Cases?

    <trackbot> Created ISSUE-9 - Should we have the media type inside
    the Test Cases? ; please complete additional details at

      [16] http://www.w3.org/2008/WebVideo/Fragments/tracker/issues/9/edit

    Let's go through each test case and spend one or two minute on each
    during a teleconf (now?)

    <mhausenblas> +1

    <conrad> +1

    <raphael> TC0000:
    _empty_MF: reviewed and agreed


    TC empty MF - Is there cases where the MF conforming UAs would
    behave differently?

    <silvia> +1

    <silvia> no

    TC0001: undefined time segment - npt - Would we expect an output?

    Do we agree that the output should be the entire resource?

    it should be unspecified?

    <silvia> I agree - it should be the entire resource

    <conrad> TC0001: +1

    <mhausenblas> Scribenick: mhausenblas

    RESOLUTION: TC0001 accepted as proposed

    <Gui_> TC0002: empty time segment - npt

    <silvia> #t=0,0 could be written as #t=x,x

    <scribe> Scribenick: Gui_

    #t=x,x, where x=x

    <conrad> i think that in barcelona we were talking about a
    zero-duration media file as the output of this

    <silvia> where x is integer

    Can a "zero duration media" be returned?

    The resource exists, it's just that we return an empty fragment of

    Should we be returning a frame as empty content?

    What is the purpose, a blank screen for Video, what about the case
    of Audio?

    Maybe this is useful as "place holders"

    Either we signal to the client that's it's a error (it's not allowed
    to do it) or it should be for some usage

    It could be in the content header, Content not acceptable 406 or 416
    the requested range is not satisfiable

    <silvia> I think: 416 Requested Range Not Satisfiable

    <raphael> I think too Silvia

    <mhausenblas> ACTION: Michael to summarise the options for 4xx
    status code for empty TC0002-0007 in a Wiki page [recorded in

    <trackbot> Created ACTION-79 - Summarise the options for 4xx status
    code for empty TC0002-0007 in a Wiki page [on Michael Hausenblas -
    due 2009-05-20].

    For all the TC returning EMPTY, what should the response be to the
    UA be (see HTTP codes)?

    <conrad> i think 416 if and only if the fragment range was given in
    an HTTP Range request header; a different error notification method
    otherwise :-)

    We need to have these resolutions (on which HTTP codes we decide to
    use) written down

    <silvia> conrad: I assumed that, too

    <conrad> eg. #track= will not be handled through Range request

    <mhausenblas> RESOLVED: The WG agrees that empty is not an error (as
    in 404) but a recoverable state

    Summarize what would the different responses be depending on the
    request (range request, others)

    <conrad> i agree with silvia

    If the UA request a fragment of the entire duration, it should get
    notified with 206

    <conrad> but 200 for TC0

    thanks conrad

    <conrad> +1

    <conrad> client should ignore stupid request and not bother wasting
    the server's time

    RESOLUTION: We agree that the HTTP response code should be 200 for

    RESOLUTION: We agree that the HTTP response code should be 200 for
    TC0000, TC0001 should be 200 and the UA strip what's behind the #

    For TC0002-6, Michael as an action

    <mhausenblas> so that #t=, -> # which makes TC0001 == TC0000 ;)

    RESOLUTION: The WG agrees that empty responses is NOT an error, so
    it's not a 404

    <conrad> +1 mhausenblas (and if we don't specify the details,
    implementers will choose arbitrarily :)

    It takes a long time to go through the TC, we need to continue doing
    so. Michael, with our resolutions, will be able to reflect changes
    on the Wiki. Thanks Michael

    <mhausenblas> ;) true, conrad. sad but true ;)

    we are running out of time, and closing the teleconf for today.

    Nothing futher to discuss? no!

    <conrad> ok!

    <silvia> cool :)

    <conrad> thanks all :-)

    Thanks you everyone! Have a nice week!


    <mhausenblas> [adjourned]

    <mhausenblas> hang on

    trackbot, status

Summary of Action Items

    [NEW] ACTION: Michael to summarise the options for 4xx status code
    for empty TC0002-0007 in a Wiki page [recorded in

    [End of minutes]

RaphaŽl Troncy
CWI (Centre for Mathematics and Computer Science),
Science Park 123, 1098 XG Amsterdam, The Netherlands
e-mail: raphael.troncy@cwi.nl & raphael.troncy@gmail.com
Tel: +31 (0)20 - 592 4093
Fax: +31 (0)20 - 592 4312
Web: http://www.cwi.nl/~troncy/
Received on Wednesday, 13 May 2009 14:27:41 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 20:52:42 UTC