- From: Adrian Bateman <adrianba@microsoft.com>
- Date: Tue, 4 Mar 2014 17:07:37 +0000
- To: Paul Cotton <Paul.Cotton@microsoft.com>, "public-html-media@w3.org" <public-html-media@w3.org>
Minutes -> http://www.w3.org/2014/03/04-html-media-minutes.html
[1]W3C
[1] http://www.w3.org/
- DRAFT -
HTML Media Task Force Teleconference
04 Mar 2014
[2]Agenda
[2] http://lists.w3.org/Archives/Public/public-html-media/2014Mar/0010.html
See also: [3]IRC log
[3] http://www.w3.org/2014/03/04-html-media-irc
Attendees
Present
paulc, markw, glenn, joesteele, adrianba,
+1.425.936.aaaa, ddorwin, davide, johnsim, pal, BobLund,
jdsmith
Regrets
Chair
Paul Cotton
Scribe
Adrian Bateman
Contents
* [4]Topics
1. [5]Roll call, introductions and selection of scribe
2. [6]NEW EME bugs since the last meeting
3. [7]Bug 24771 - Provide guidance on object and CDM
lifetime (including when events are guaranteed to be
fired)
4. [8]Bug 24873 - Current isTypeSupported() definition
does not provide sufficient information to
applications
5. [9]Bug 24874 - Positive isTypeSupported() may be
misleading (MSE vs. .src=)
6. [10]Bug 24904 - Uint8Array parameters should not be
modifiable after method calls return
7. [11]EME bugs for discussion
8. [12]Bug 17673 - Define Initialization Data for
implementations that choose to support the ISO Base
Media File Format
9. [13]Bug 17750 - Define the behavior MediaKeySession
close() and clearing the keys attribute
10. [14]Bug 21798 - Revisit MediaKeyError codes
11. [15]Bug 23619 - Change MediaKeyError to extend
DOMError and use strings for error names
12. [16]Bug 24027 - Define a generic Initialization Data
solution for ISO Base Media File Format and/or Common
Encryption (will be used by Clear Key)
13. [17]Bug 24419 - Clear Key: Define license request
format
14. [18]Bug 24673 - Make all content type string checks
case-sensitive
15. [19]Any other business
16. [20]Adjournment
* [21]Summary of Action Items
__________________________________________________________
<trackbot> Date: 04 March 2014
<paulc> Agenda:
[22]http://lists.w3.org/Archives/Public/public-html-media/2014M
ar/0010.html
[22] http://lists.w3.org/Archives/Public/public-html-media/2014Mar/0010.html
<scribe> Agenda:
[23]http://lists.w3.org/Archives/Public/public-html-media/2014M
ar/0010.html
[23] http://lists.w3.org/Archives/Public/public-html-media/2014Mar/0010.html
<scribe> ScribeNick: adrianba
<scribe> Scribe: Adrian Bateman
Roll call, introductions and selection of scribe
paulc: done
NEW EME bugs since the last meeting
paulc: there are 4 of these
... one of them had a lot of discussion but the others not so
much
Bug 24771 - Provide guidance on object and CDM lifetime (including
when events are guaranteed to be fired)
[24]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24771
[24] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24771
<paulc>
[25]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24771
[25] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24771
paulc: long proposal here - do you just want to add this to the
list of things of comments or should david introduce the
issues?
ddorwin: issue came up when deciding when to GC the objects -
could be a circular reference meaning things wouldn't get
collected
paulc: volunteer to review?
<markw> I will review it too, but I am also not a browser
vendor
joesteele: i could review but not sure if my input would be as
useful - not a browser vendor
paulc: perhaps someone from Microsoft can take a look at this
Bug 24873 - Current isTypeSupported() definition does not provide
sufficient information to applications
[26]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24873
[26] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24873
paulc: filed recently - does this fall into the same category?
ddorwin: not being able to detect if the browser has
capabilities needed - adrian mentioned this in one of the other
bugs
<joesteele> +q
ddorwin: first two paragraphs says what it is - the rest says
why
... two changes - one if to add capability string and the other
is changing the return type to have three states
... somewhat like canPlayType though doesn't have to be
... those are independent but work well together
joesteele: seems to reintroduce something we discussed at the
beginning
... decided early on the key systems shouldn't have this info
because it was too complicated
ddorwin: some of the same issues but this is more targeted
specifically at audio vs video
... but we decided not to 'abuse' the key system name
joesteele: maybe i'm not understanding capability - do you mean
things like HDCP
... is this something where this platform is not at all capable
or not right now
... because if not right now then you'd need to call again
ddorwin: no, i wasn't thinking about HDCP which can take a
couple of seconds
... this is supposed to return quickly
... many key systems support multiple levels of robustness
<ddorwin> The old capability detection bug:
[27]https://www.w3.org/Bugs/Public/show_bug.cgi?id=16611
[27] https://www.w3.org/Bugs/Public/show_bug.cgi?id=16611
adrianba: not sure what the capability string contains - what
if it is more than one thing - should it be a string or
something else?
ddorwin: it is key system specific - could have a key system
specific separator
... could have an array of strings but just as easy to be comma
separated
Bug 24874 - Positive isTypeSupported() may be misleading (MSE vs.
.src=)
[28]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24874
[28] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24874
ddorwin: result of isTypeSupported doesn't say if it works with
MSE or with src=
... filed to track this issue
paulc: questions?
Bug 24904 - Uint8Array parameters should not be modifiable after
method calls return
[29]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24904
[29] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24904
paulc: provided the beginning of the march part of the thread
[30]http://lists.w3.org/Archives/Public/public-html-media/2014M
ar/0002.html
[30] http://lists.w3.org/Archives/Public/public-html-media/2014Mar/0002.html
paulc: most recent suggestion to raise this as a TAG issue
<joesteele> +1 to email discussion
paulc: shall we let this continue in email? this problem exists
in other places too
EME bugs for discussion
paulc: all the bugs that had postings since our last meeting
... agenda item 7 includes implemented bugs since last time (4
bugs)
... agenda item 8 is bugs waiting for editors (6 bugs)
... agenda item 9 is low pri bugs
... plan to step through the items in #6 and ignore the others
today
Bug 17673 - Define Initialization Data for implementations that
choose to support the ISO Base Media File Format
[31]https://www.w3.org/Bugs/Public/show_bug.cgi?id=17673
[31] https://www.w3.org/Bugs/Public/show_bug.cgi?id=17673
adrianba: we think we should move ahead with changing this as
discussed in recent meetings to see if people like the text
... (that's Microsoft's position)
<joesteele> no objection
paulc: any comments?
... any objections to trying this out?
... okay, this one is assigned to the editors to do
adrianba: i'm happy to make the change
ddorwin: i'll file a specific bug about the "CENC" string - i
suspect we'll need to change isTypeSupported too
Bug 17750 - Define the behavior MediaKeySession close() and clearing
the keys attribute
[32]https://www.w3.org/Bugs/Public/show_bug.cgi?id=17750
[32] https://www.w3.org/Bugs/Public/show_bug.cgi?id=17750
paulc: comment from adrian on feb 21
<joesteele> +q
adrianba: we reviewed this and think we're proposing the
correct answer - we need someone to check our working
ddorwin: no specific objections
markw: looks okay - i will check with our implementers
joesteele: i had raised a question above about cached keys
being released
... not clear to me that we agree that keys can be cached
... might be off topic for this bug
adrianba: i think loadSession implies there are cached keys
otherwise what could you load
... i think there is a question beyond just consistency with
other specs - we proposed a solution that does impact what
order things can execute in
... so there is something EME specific to review here too
glenn: haven't looked at the detail but curious if there is a
need for promises here?
<ddorwin> Does the proposed spec change related to spinning the
event loop mean MediaKeys construction will prevent any other
tasks (from any other spec) from being processed? Is that
desirable?
adrianba: i don't think promises apply here - this is about
multiple async tasks interacting with each other
<glenn> sleep(0)
adrianba: spinning the event loop is like VB6 DoEvents - it
lets other things run
paulc: is there an editor to implement this?
adrianba: i can do this
Bug 21798 - Revisit MediaKeyError codes
[33]https://www.w3.org/Bugs/Public/show_bug.cgi?id=21798
[33] https://www.w3.org/Bugs/Public/show_bug.cgi?id=21798
adrianba: we can live with not solving this in this version but
if someone comes up with a workable proposal then we are okay
with that
ddorwin: i will make a proposal
Bug 23619 - Change MediaKeyError to extend DOMError and use strings
for error names
[34]https://www.w3.org/Bugs/Public/show_bug.cgi?id=23619
[34] https://www.w3.org/Bugs/Public/show_bug.cgi?id=23619
<ddorwin> Open issue in DOM4 on the future of DOMError:
[35]http://www.w3.org/TR/dom/#interface-domerror
[35] http://www.w3.org/TR/dom/#interface-domerror
adrianba: while the spec continues to have DOMError, we think
we're using it correctly
... we also prefer to keep systemCode
<joesteele> +1 to keeping it in the spec as-is
ddorwin: i don't object to system code and the inclusion
requires that we define an additional type - if people want to
keep it then that is fine - it is already in the spec
paulc: what is next?
ddorwin: if nobody wants to eliminate this type then we
resolve, fixed
paulc: proposal is to mark it fixed
<ddorwin> done
Bug 24027 - Define a generic Initialization Data solution for ISO
Base Media File Format and/or Common Encryption (will be used by
Clear Key)
[36]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24027
[36] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24027
paulc: mark agreed to add a concrete proposal - in comment 6
... some dialogue here - what is the current state?
markw: i didn't see the questions from joe and david so i need
to catch up and reply to their points
joesteele: i should reply in the bug - i wasn't clear from
david's last question why you wouldn't want to use the MAC - i
would guess that the CDM would say key not available
ddorwin: some confusion about what the MAC was earlier in
thread - agree - question is do the existing algorithms deal
with this
Bug 24419 - Clear Key: Define license request format
[37]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24419
[37] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24419
paulc: is this ready to move to the "to be implemented" list?
ddorwin: need to implement the license request format first
Bug 24673 - Make all content type string checks case-sensitive
[38]https://www.w3.org/Bugs/Public/show_bug.cgi?id=24673
[38] https://www.w3.org/Bugs/Public/show_bug.cgi?id=24673
ddorwin: we find that the content type and the codecs have
different requirements
... so we might need non-normative text
adrianba: seems fine - just need text to add
paulc: do we need concrete text in the bug or just move forward
- better to move ahead
ddorwin: will make this dependent on the "CENC" bug that I said
I will file
Any other business
paulc: i said we'd skip the other bugs unless someone objects -
now is the time if you want to
... in 10 days i'll evaluate where we stand for the topic bugs
for discussion in the next meeting
adrianba: different topic, are people planning to attend the
F2F meeting to discuss EME?
<markw> yes, I'll be there
<BobLund> I'll be there
paulc: [lists attendees from TF who already plan to attend]
<paulc>
[39]https://www.w3.org/2002/09/wbs/40318/html-april-2014/result
s
[39] https://www.w3.org/2002/09/wbs/40318/html-april-2014/results
paulc: if you can't attend might be helpful to fill out the
registration form saying so
joesteele: i may have a conflict - probably be on the phone at
least
ddorwin: would be nice if we knew which day to minimise travel
<paulc>
[40]https://www.w3.org/wiki/HTML/wg/2014-04-Agenda#Potential_To
pics
[40] https://www.w3.org/wiki/HTML/wg/2014-04-Agenda#Potential_Topics
paulc: if you put it on the potential topics list then we can
reserve that time
... meeting is tues/wed
<BobLund> Tue or Wed AM
<paulc> April 8-9
paulc: does anyone have a pref for which day
johnsim: if the meeting is wed AM i might be able to attend
paulc: any objections to wed AM?
<BobLund> Wed AM is good
adrianba: works for me
paulc: would it be worth asking dsinger about attending?
pal: excellent idea
paulc: i'll propose on the draft agenda - should i ask for 9 to
11?
... i'll figure this out
Adjournment
paulc: talk to you in 2 weeks
Summary of Action Items
[End of minutes]
-----Original Message-----
From: Paul Cotton [mailto:Paul.Cotton@microsoft.com]
Sent: Monday, March 3, 2014 6:06 PM
To: public-html-media@w3.org
Subject: {agenda} HTML WG media telecon 2014-03-04 - EME bug discussion
The HTML WG media teleconference meeting will occur on 2014-03-04 for up to 60 minutes from 15:00Z to 16:00Z.
http://timeanddate.com/s/2jfn
Tokyo midnight, Amsterdam/Oslo 17:00, London/Dublin 16:00, New Jersey/York 11:00, Kansas City 10:00, Seattle/San Francisco 08:00.
Chair of the meeting: Paul Cotton
Scribe: TBD
(See the end of this email for dial-in and IRC info.)
== Agenda ==
1. Roll call, introductions and selection of scribe
2. Previous meeting minutes
Feb 18: http://www.w3.org/2014/02/18-html-media-minutes.html
Feb 4: http://www.w3.org/2014/02/04-html-media-minutes.html
Jan 28: http://www.w3.org/2014/01/28-html-media-minutes.html
3. Review of action items and issues
https://www.w3.org/html/wg/media/track/
a) ACTION-61: Work with wendy to make sure we get a security review [ Paul ]
https://www.w3.org/html/wg/media/track/actions/61
Status: Paul reached out to Wendy again on Jan 23:
http://lists.w3.org/Archives/Public/public-html-media/2014Jan/0056.html
b) ACTION-62: Report back about the plan for 20944 due 2013-12-15 [ Paul ]
https://www.w3.org/html/wg/media/track/actions/62
Status: No action yet but see developments on 20944:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=20944#c34
and subsequent replies.
4. EME status and bugs
a) Encrypted Media Extensions editor's draft
http://dvcs.w3.org/hg/html-media/raw-file/tip/encrypted-media/encrypted-media.html
Last updated on Feb 24.
b) Encrypted Media Extensions bugs:
http://tinyurl.com/7tfambo
Status as of Mar 3: 22 bugs
5. NEW EME bugs since the last meeting
a) Bug 24771 - Provide guidance on object and CDM lifetime (including when events are guaranteed to be fired)
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24771
b) Bug 24873 - Current isTypeSupported() definition does not provide sufficient information to applications
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24873
c) Bug 24874 - Positive isTypeSupported() may be misleading (MSE vs. .src=)
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24874
d) Bug 24904 - Uint8Array parameters should not be modifiable after method calls return
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24904
See also the thread at:
http://lists.w3.org/Archives/Public/public-html-media/2014Mar/0002.html
6. EME bugs for discussion
a) Bug 17673 - Define Initialization Data for implementations that choose to support the ISO Base Media File Format
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17673
See recent postings since Feb 18 meeting:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17673#c42
b) Bug 17750 - Define the behavior MediaKeySession close() and clearing the keys attribute
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17750
See recent response from Adrian since Feb 18 meeting:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17750#c26
c) Bug 21798 - Revisit MediaKeyError codes
https://www.w3.org/Bugs/Public/show_bug.cgi?id=21798
Status from Jan 28 meeting: Error codes and constants removed. New error names need to be proposed and added.
Feb 4: David said he would go through whole thread and generate a response.
See recent response from Adrian since Feb 18 meeting:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=21798#c19
d) Bug 23619 - Change MediaKeyError to extend DOMError and use strings for error names
https://www.w3.org/Bugs/Public/show_bug.cgi?id=23619
See recent response from Adrian since Feb 18 meeting:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=23619#c10
e) Bug 24027 - Define a generic Initialization Data solution for ISO Base Media File Format and/or Common Encryption (will be used by Clear Key)
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24027
Mark agreed added a concrete proposal after Feb 18 meeting:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24027#c6
f) Bug 24419 - Clear Key: Define license request format
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24419
Feb 4: David said he would implement the proposed solution. But see Adrian's question:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24419#c1
g) Bug 24673 - Make all content type string checks case-sensitive
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24673
See Adrian and David's dialogue starting at:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24673#c2
7. Implemented EME bugs awaiting review
a) Bug 18515 - Provide more details on behavior of the media element when the key for an encrypted block is not available
https://www.w3.org/Bugs/Public/show_bug.cgi?id=18515
Implemented and awaiting review:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=18515#c21
b) Bug 24270 - Make MediaKeySession State Definitions and Event Summary sections non-normative
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24270
c) Bug 24323 - Rename "First Time a Key Reference is Encountered" algorithm and remove key ID checks from Container Guidelines subsections
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24323
d) Bug 24368 - Define playback behavior when the key for an encrypted block is not available for a subset of streams
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24368
8. EME bugs awaiting Editor implementation or action
a) Bug 17202 - Explicitly document how keys are to be shared
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17202
Next action: David to make changes in comment 3
b) Bug 17682 - Clear Key: Document how keys and key IDs are associated
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17682
Next action: David to add note.
c) Bug 23828 - HTMLSourceElement with |keySystem| attribute should create MediaKeys object for |keySystem|
https://www.w3.org/Bugs/Public/show_bug.cgi?id=23828
Next action: Adrian to make changes (low priority - see 23827)
d) Bug 24026 - Document that URLs (destinationURL) should/may be validated and/or normalized
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24026
Next action: David to add proposed text (to bug or spec)
e) Bug 24081 - The READY state is too limiting and should be more like the PENDING state
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24081
Next action: TF to discuss David's proposal (Microsoft is supportive)
Status from Jan 28 meeting: David to implement his proposal.
f) Bug 24216 - setMediaKeys() needs more specification
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24216
David agreed to develop a proposal:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24216#c2
9. EME bugs on hold or lower priority
a) Bug 20944 - EME should do more to encourage/ensure CDM-level interop
https://www.w3.org/Bugs/Public/show_bug.cgi?id=20944
Next action: ACTION-62 on Paul
b) Bug 23827 - Need to add features at risk prior to entry into Candidate Recommendation
https://www.w3.org/Bugs/Public/show_bug.cgi?id=23827
Next action: wait until LC
c) Bug 24025 - Add optional configuration parameter to MediaKeys constructor
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24025
Next action: discuss as part of 24082 below. Tied to the general extensibilty issue.
Mark added his use case on Feb 18:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24025#c9
d) Bug 24082 - Several issues discussed in the TF point to the need for defined extensibility points in EME
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24082
Next action: TF agreed that members need to propose use cases - not blocking and lower priority
e) Bug 24322 - Reorganize spec by object
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24322
Next action: significant editorial change just needs editing - not blocking
10. Any other business
11. Chair and Scribe for next meeting
12. Adjournment
== Dial-in and IRC Details ==
Zakim teleconference bridge:
+1.617.761.6200, conference 63342 ("media")
https://www.w3.org/Guide/1998/08/teleconference-calendar#s_5366
Supplementary IRC chat (logged):
#html-media on irc.w3.org port 6665 or port 80 Paul Cotton, Microsoft Canada
17 Eleanor Drive, Ottawa, Ontario K2E 6A3
Tel: (425) 705-9596 Fax: (425) 936-7329
Paul Cotton, Microsoft Canada
17 Eleanor Drive, Ottawa, Ontario K2E 6A3
Tel: (425) 705-9596 Fax: (425) 936-7329
Received on Tuesday, 4 March 2014 17:08:15 UTC