HTML/wg/2015-04-Agenda

Media Task Force April 15-16 2015 F2F Meeting

This page is for the HTML WG Media Task Force F2F on Wed and Thu April 15-16 2015. The meeting host is Paul Cotton.

Logistics and meeting location

The F2F meeting will be held on the Microsoft campus in Redmond, WA in the Shasta conference room of Building 43.

Microsoft Building 43 (East Campus) 15580 NE 31st St. Redmond, WA 98052, United States Note: If you have difficulty using the link please do a search for the street address.

There is an underground parking garage between buildings 42 and 43 that you can use. Please register your vehicle at the Building 43 reception.

The meeting will start at 9:30am PT on Wed Apr 15. Please arrive at the Building 43 reception between 9am and 9:15am on Wed Apr 15 to register and to be accompanied to the meeting room.

IRC and Teleconference facilities

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 

Specifications, Documents and References:

Media Task Force specifications

• Media Source Extensions Editor's Draft
• Encrypted Media Extensions Editor's Draft

EME bugs and issues

• Encrypted Media Extensions bugs
• EME GitHub issues

MSE bugs

• Media Source Extensions bugs

See also:

• HTML WG homepage
• HTML WG and TF Publications

Potential Topics

MSE

1. Plan for getting MSE out of CR (i.e. MSE test suite status) - Wed 5pm time slot requested to permit Mike Smith to join from Japan
2. Selected MSE bugs
   1. MSE does not work with Mixed Content, unlike video/audio.src=
   2. Clarify how track buffer ranges are updated.
3. [Rus K] Use cases driving additional content insertion requirements.

EME

1. [ddorwin] Interoperability
2. [markw, ddorwin] Secure origin requirement.
   1. Bug 26332
   2. David's email on enabling Mixed Content
3. [ddorwin] persistent-release-message session type
   1. ISSUE-45 Remove "persistent-release-message" MediaKeySessionType
4. [markw] Persistent secure release messages (Issues 45,16)
   1. ISSUE-45 Remove "persistent-release-message" MediaKeySessionType
   2. ISSUE-16 Review close() and remove() logic and behavior for persistent-* sessions
5. [ddorwin] Bug 27269 about partitioning identifiers and data by top-level *and* EME-using origin
6. [steele] Resolve Bug 27093 about allowing keys in initData
   1. The discussion is really in https://github.com/w3c/encrypted-media/issues/41.
7. [skip if no owner] Review the disposition of the session/key persistence issues 18,20,26
   1. ISSUE-18 MediaKeySession.remove() and close() should mark session's keys as "unknown"
   2. ISSUE-20 Ensure session type is correct for loaded sessions
   3. ISSUE-26 Require that the license match the session type
8. [steele] Discuss appetite for common license request/response format?
   1. Joe's email
   2. https://github.com/steelejoe/eme-generic-protocol
   3. Related: Bug 27053 - Platform Segmentation
   4. Related: Bug 20944 - EME should do more to encourage/ensure CDM-level interop
9. [steele] Revisit the EME use cases wiki?
10. [ddorwin] Automatically publishing to TR/
    1. W3C now has a self-serve/automatable tool for publishing to www.w3.org/TR/xyz.
    2. Eliminates W3C Team involvement/dependency and reduces/eliminates the lag of the TR/ URL.
    3. HTML 5.1 is now automatically published soon after a commit.
    4. Note: Not an option for MSE because it only supports WDs.

Moving the EME spec forward

1. Plan for Bug 26573 Getting EME to last call
   1. Permanent home for EME registry.
2. Plan for addressing interop/segmentation bugs:
   1. Bug 20944 - EME should do more to encourage/ensure CDM-level interop
   2. Bug 27053 - Platform Segmentation
3. [ddorwin] What is the definition of independent interoperable implementations for EME?
4. [ddorwin] Tests - Should we use MSE rather than .src= for spec tests?

Other

1. [ddorwin] Telecon frequency, agenda, etc.
2. [A11Y TF] Discussion of transcript accessibility and HTML ISSUE-194 (Requested to be at 4pm on Wed)

EME open bugs and issues

• Encrypted Media Extensions Bugzilla bugs

• Bug 20944 - EME should do more to encourage/ensure CDM-level interop depends on:
  • Bug 27053 - Platform Segmentation
  • Bug 27093 - Support for proprietary/system-specific formats in initData should be discouraged/deprecated
• Bug 23827 - Need to add features at risk prior to entry into Candidate Recommendation
• Bug 26838 - Normatively address vulnerabilities related to initData contained in media data depends on:
  • Bug 26332 - Applications should only use EME APIs on secure origins (e.g. HTTPS)
  • Bug 27093 - Support for proprietary/system-specific formats in initData should be discouraged/deprecated
• Bug 26573 - Prepare for Last Call depends on:
  • Bug 26811 - Separate definitions of Initialization Data Types from Stream Format parsing
• Bug 26738 - Add entry for MPEG-2 TS CENC to the Stream Format Registry depends on:
  • Bug 26811 - Separate definitions of Initialization Data Types from Stream Format parsing
• Bug 26776 - Diagnosing and resolving CDM errors needs a numeric systemCode (deleted with MediaKeyError)
• Bug 26887 - Allowing license servers and CDMs to control data persistence and secure release
• Bug 27054 - Accessibility Concerns
• Bug 27055 - Surfacing license to the user
• Bug 27067 - Define what to do when CDM becomes unavailable
• Bug 27168 - Individualization text regarding device identifiers is overbroad and should be more specific
• Bug 27269 - Normatively require distinctive identifiers to be different by top-level and EME-using origin depends on:
  • Bug 27268 - Add a definition of a distinctive identifier
• Bug 27271 - Normatively require https for all ancestor origins when requiring https at all depends on:
  • WHATWG Bug 27190 - Add TLS state to environment settings objects. This is needed for Fetch and Mixed Content ...
  • WebAppSec Bug 27302 - Define an elaboration of #may-document-use-powerful-features that checks ancestor browsing contexts
• Bug 27283 - InvalidAccessError usage is questionable; use TypeError instead? depends on:
  • WebApps Bug 27284 - Should InvalidAccessError be discouraged?
• EME GitHub issues
• ISSUE-14 Consider changing how the MediaKeySession method algorithms run other algorithms to more accurately reflect implementations depends on:
  • ISSUE-19 Ensure promises returned by methods are fulfilled before event handlers are executed
• ISSUE-22 Request: Require CDMs to support and enforce resolution restrictions (and expose the status of those restrictions to the application)
• ISSUE-23 CDM implementations must support multiple keys per session
• ISSUE-31 generateRequest() should allow the first message to not be a license request based on initData depends on:
  • ISSUE-19 Ensure promises returned by methods are fulfilled before event handlers are executed
• ISSUE-41 generateRequest may result in keys being usable when no key request needs to be sent
• ISSUE-42 Notification when playback is resumed from waitingForKey
• ISSUE-45 Remove "persistent-release-message" MediaKeySessionType
• ISSUE-47 MediaKeySystemConfiguration.sessionTypes should be sequence<DOMString> for forwards compatibility
• ISSUE-48 Clear Key should not use "A128KW" as the JWK "alg"

EME open bugs - pending implemention

• Bug 27725 - Missing acknowledgments section
• ISSUE-2 stack_overview.svg needs to be updated to match the latest spec
• ISSUE-8 Define behavior for implementations that delay playback until setMediaKeys() is called
• ISSUE-9 Remove note that MediaKeySession events may not be fired until the MediaKeys object is associated with a media element
• ISSUE-10 Include real initData and Clear Key license in the Clear Key example
• ISSUE-12 MediaKeySystemConfiguration returned from MediaKeySystemAccess::getConfiguration() should contain the exact strings from requestMediaKeySystemAccess()
• ISSUE-15 MediaKeySystemAccess::getConfiguration() should return a read-only object (copy)
• ISSUE-17 Replace "fire a simple event" with "fire an event" for non-simple Events
• ISSUE-20 Ensure session type is correct for loaded sessions
• ISSUE-30 Switch terminology from "asynchronously" to "in parallel"
• ISSUE-32 Consider providing guidance for implementations on platforms that do not expose key IDs
• ISSUE-34 Replace base64url values in examples with realistic values that use base64url-specific characters
• ISSUE-36 Explicitly state that MediaKeySystemMediaCapability's contentType attribute MUST be a valid MIME type
• ISSUE-39 MediaKeyStatusMap: Replace maplike with explicit methods
• ISSUE-43 Provide guidance on object and CDM lifetime
• ISSUE-44 Idea: Add opaque "label" DOMString member to MediaKeySystemConfiguration

MSE open bugs

• Media Source Extensions Bugzilla bugs

• Bug 27239 - Update SourceBuffer.appendStream() and related algorithms to use ReadableByteStream
• Bug 27242 - Clarify how track buffer ranges are updated
• Bug 27790 - Some of the attributes returning TimeRanges objects seem to return a new object each time the getter is invoked
• Bug 27843 - Should the media element load algorithm trigger detaching from a media element?
• Bug 27854 - Should fetch algorithm failure trigger detaching from a media element?
• Bug 27980 - Ambiguous behaviour when running sourcebuffer.abort()
• Bug 27982 - Clarify asynchronicity in duration change algorithm when reducing duration

• Bug 28379 - should buffering model be an option?
• Bug 28465 - MSE does not work with Mixed Content, unlike video/audio.src=

Recently fixed bugs:

• Bug 28209 - Confusing text, might be better off without it
• Bug 28234 - "highest presentation timestamp" is ambiguous/misleading

Agenda April 15

• 09:30 - 10:15 Tweak agenda à la an unconference style meeting
• 10:00 - 11:00 MSE bugs 28465, 27242, 27239 and other MSE topics
• 11:00 - 12:30 EME session 1
• 12:30 - 13:30 Lunch break
• 13:30 - 15:00 EME session 2
• 15:00 - 15:30 Coffee break
• 15:30 - 16:00 EME session 3
• 16:00 - 17:00 [A11Y TF] Discussion of transcript accessibility and HTML ISSUE-194
• 17:00 - 18:00 Plan for getting MSE out of CR (i.e. MSE test suite status) - Wed 5pm time slot requested to permit Mike Smith to join from Japan

Agenda April 16

• 09:00 - 10:00 EME Session 4
• 10:00 - 11:00 EME Session 5
• 11:00 - 12:15 ISSUE-45
• 12:15 - 13:15 Lunch break
• 13:15 - 15:00 EME Session 6
• 15:00 - 15:30 Coffee break
• 15:30 - 17:00 EME Session 7 and any other business