- From: Raphaël Troncy <raphael.troncy@eurecom.fr>
- Date: Wed, 13 Apr 2011 12:24:03 +0200
- To: Media Fragment <public-media-fragment@w3.org>
Dear all,
The minutes of today's phone telecon are available for review at
http://www.w3.org/2011/04/13-mediafrag-minutes.html (and in text format
below).
Outstanding new ACTIONS:
* Davy to edit the specification to precise what is the user
experience when there is an invalid time range
* Jack to carefully review the changes made by Davy that will most
likely be all over the place
Everybody (minus Davy and Raphael) has committed to be here next week to
continue the test cases discussion.
Best regards,
Raphaël
-----------
[1]W3C
[1] http://www.w3.org/
Media Fragments Working Group Teleconference
13 Apr 2011
[2]Agenda
[2]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Apr/0042.html
See also: [3]IRC log
[3] http://www.w3.org/2011/04/13-mediafrag-irc
Attendees
Present
Yves, Raphael, Davy, Philip, Jack, Silvia
Regrets
Erik, Thomas
Chair
Raphael
Scribe
raphael
Contents
* [4]Topics
1. [5]1. ADMIN
2. [6]2. SPEC MAINTENANCE
3. [7]3. TEST CASES
4. [8]4. AOB
* [9]Summary of Action Items
_________________________________________________________
<trackbot> Date: 13 April 2011
1. ADMIN
PROPOSED to accept the minutes of the last week telecon,
[10]http://www.w3.org/2011/04/06-mediafrag-minutes.html ?
[10] http://www.w3.org/2011/04/06-mediafrag-minutes.html
<foolip> +1
+1
<davy> +1
minutes accepted
<scribe> Scribe: raphael
<scribe> Scribenick: raphael
TPAC 2011, [11]http://www.w3.org/2011/11/TPAC/
[11] http://www.w3.org/2011/11/TPAC/
Raphael: do you think we should meet?
Jack: hard to say now, because we don't know what would be the
status of the work
Yves: I think if we need a F2F, better in Europe and earlier
Raphael: Media Fragment WG does NOT plan to meet at TPAC
2. SPEC MAINTENANCE
Precision of #xywh percent
scribe: thread starting at
[12]http://lists.w3.org/Archives/Public/public-media-fragment/2011Ap
r/0022.html
[12]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Apr/0022.html
Philip: two issues
<foolip> rounding issue:
[13]http://lists.w3.org/Archives/Public/public-media-fragment/2011Ap
r/0011.html
[13]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Apr/0011.html
Philip: first one is rounding
... second one is the precision
... what is the use case, e.g. cropping a video?
... do we really need the percent syntax?
... the use case seems to be the existence of multiple encoding in
multiple resolutions for the same video
Jack: I think you're right
... the % syntax is for very simple cases, such as take the half of
a video
Philip: but when does it make sense to do this?
... the change of 4/3 to 16/9 implies percent with decimal
... so our syntax does not do this
Yves: aspect ratio could be handled with a new 'aspect' keyword
... but Sylvia was against this, because it is too complex
... and not enough uses of this
... I'm not for or against the % syntax
... we can let it and see whether there will be implementations
Jack: I think we should keep it and see whether there will be
implementations
... and take it out if no tools
<davy> [14]http://ninsuna.elis.ugent.be/Media/Showcase/Radiohead
[14] http://ninsuna.elis.ugent.be/Media/Showcase/Radiohead
Jack: rather than inventing decimal percentages
Davy: we DO use the percent syntax !
... in the example above, we need the % to swith resolution
Philip: you have a server and each resolution have different URI
Davy: yes we could do the computation on the server, but now, the
annotations are independent of the resolution
... annotations are about logical URI
<Yves> conneg on user-agent for different resolution
Jack: the syntax is then more interesting for annotating than
cropping
Yves: conneg on UA for different resolution, and cropping are
"roughly"
Philip: is this implemented anywhere?
Yves: Opera is adapting content for mobile devices ... they do adapt
resolution ?
Philip: yes, but you still have different URI
... for caching purposes
Yves: not in the case where it is done via proxy
Philip: seems like a corner case
Jack: I think the use case from Davy, mainly for annotation purpose,
is an appealing one
... and not for browsers
Philip: should we write this in the spec?
Raphael: proposal to keep it in the spec and see the implementations
that will do something with it
... no disagreement
3. TEST CASES
Davy: first some changes, I have implemented the changes according
to last week
... more filters
... more test cases (the ones from Philip)
<davy>
[15]http://lists.w3.org/Archives/Public/public-media-fragment/2011Ap
r/0031.html
[15]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Apr/0031.html
Davy: I think we should first discuss
[16]http://lists.w3.org/Archives/Public/public-media-fragment/2011Ap
r/0031.html
... Invalid syntax
... #t=3,4,4 is invalid syntax
... what the UA should do
... disagreement: UA only requests setup information (Silvia) vs
whole resource is requested by the UA (Philip)
[16]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Apr/0031.html
Jack: I don't really care as soon as it is consistent
Yves: the same
<scribe> ACTION: raphael to ask Silvia if she objects to the
decision of requesting the entire resource in case of an invalid
syntax [recorded in
[17]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action01]
<trackbot> Sorry, couldn't find user - raphael
<scribe> ACTION: troncy to ask Silvia if she objects to the decision
of requesting the entire resource in case of an invalid syntax
[recorded in
[18]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action02]
<trackbot> Created ACTION-216 - Ask Silvia if she objects to the
decision of requesting the entire resource in case of an invalid
syntax [on Raphaël Troncy - due 2011-04-20].
Davy: Invalid Semantics
... case a): #t=7,3 is invalid semantically ... again same
possibility
<foolip> Range: t:npt=3-7;include-setup
Philip: what does it mean include-setup? Does it mean to implement
the new headers?
... I'm not in favor of implementing this
... in particular when browsers have other means to receive the
setup data
<davy> Range: include-setup
<tomayac> FWIW, in mediafragments.js, all incorrect parameter
configurations are silently ignored, a warning is raised if verbose
mode is enabled
<tomayac> (following the meeting on IRC)
Jack: for temporal fragment, what is important is the user
experience
... we do not care if he uses byte ranges or our newly introduced
mechanism
Raphael: BIG +1 to Jack
Jack: so if I put #t=7,3, I got the timeline and no portion selected
... should not be the same with #t=banana?
Philip: there are things that will be harder to detect during
parsing
... e.g. #xywh=150%
<jackjansen> Note that I put up that suggestion (t=7,3 vs t=banana)
as a point for discussion, not as my standpoint.
Philip: so #t=7,3 will be ignored, first frame displayed, and NOT
the frame at second 7 or 3
<tomayac> in mediafragments.js, most basic things get captured via
regexps (like t=2,banana), however, harder ones like start < end are
harder (given all the options)
Philip: but #t=15,20 for a video of a duration of 10s will be
different
<tomayac> i cant check for end <= video_duration
<tomayac> the default assumption in the lib is to always return the
whole resource if anything cant be parsed correctly
Philip: and what about #t=20,80 when the video is of duration 50s ?
Davy: come back to #t=15,20 for a video of a duration of 10s
... I'm not saying that the UA should issue a range request
... but if it does, then server should reply with a 416
Jack: what is the user experience?
Davy: I agree with Philip, the player should seek towards the end
(display the last frame?)
... to be consistent with HTML5
<jackjansen> silvia, the good news is that we've now been able to
give you heaps of action points:-)
<silvia> hahaha, sure!
<silvia> I probably just checked my calendar for the usual time,
rather than your announcement - sorry :(
<silvia> were you able to agree on things?
<foolip> do we need to support media that doesn't start at 0 ?
<scribe> ACTION: davy to edit the specification for precising what
is the user experience when there is an invalid time range [recorded
in [19]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action03]
<trackbot> Created ACTION-217 - Edit the specification for precising
what is the user experience when there is an invalid time range [on
Davy Van Deursen - due 2011-04-20].
<foolip> that comes up in the test case review, let's discuss in due
course
<scribe> ACTION: jack to carrefully review the changes made by Davy
that will most likely be all over the palce [recorded in
[20]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action04]
<trackbot> Created ACTION-218 - Carrefully review the changes made
by Davy that will most likely be all over the place [on Jack Jansen
- due 2011-04-20].
Raphael: should we postpone the discussion "do we need to support
media that doesn't start at 0 ?" to next week ?
Jack: let's do that on the mailing list
... Dave Singer may have an opinion
<foolip> so, I was muted and afk, so unable to unmute
<foolip> I'm fine with postponing
<foolip> ok
Raphael: summarizing the first issue for Silvia
Silvia: I'm fine with requesting the whole resource
<jackjansen> I have to run: next appointment. See you next week!
Silvia: I'm not able to remember when the include-setup will be used
close ACGTION-217
close ACTION-217
<trackbot> ACTION-217 Edit the specification for precising what is
the user experience when there is an invalid time range closed
close ACTION-216
<trackbot> ACTION-216 Ask Silvia if she objects to the decision of
requesting the entire resource in case of an invalid syntax closed
4. AOB
Regrets from Davy for next week
<foolip> bye
scribe: we will continue discussing test cases next week
Summary of Action Items
[NEW] ACTION: davy to edit the specification for precising what is
the user experience when there is an invalid time range [recorded in
[21]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action03]
[NEW] ACTION: jack to carrefully review the changes made by Davy
that will most likely be all over the palce [recorded in
[22]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action04]
[NEW] ACTION: raphael to ask Silvia if she objects to the decision
of requesting the entire resource in case of an invalid syntax
[recorded in
[23]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action01]
[NEW] ACTION: troncy to ask Silvia if she objects to the decision of
requesting the entire resource in case of an invalid syntax
[recorded in
[24]http://www.w3.org/2011/04/13-mediafrag-minutes.html#action02]
[End of minutes]
_________________________________________________________
--
Raphaël Troncy
EURECOM, Multimedia Communications Department
2229, route des Crêtes, 06560 Sophia Antipolis, France.
e-mail: raphael.troncy@eurecom.fr & raphael.troncy@gmail.com
Tel: +33 (0)4 - 9300 8242
Fax: +33 (0)4 - 9000 8200
Web: http://www.eurecom.fr/~troncy/
Received on Wednesday, 13 April 2011 10:24:14 UTC