Web and TV Interest Group Teleconference

02 Feb 2012


See also: IRC log


Kazuyuki, Mark_Vickers, Clarke, glenn, Bryan_Sullivan, Duncan, Jason, Franck, John_Simmons, Russell, Philipp, Bob_Lund, Kilroy_Hughes


scribe list

<kaz> scribe list

See Scribe Schedule on wiki

Reorganizing site

clarke: will take first shot at organizing site. Will take suggestions.

Scheduling of work on content protection

clarke: Current plan: 1st adaptive bitrate, 2nd: content protection

jason: content protection bigger issue for content industry, so don't put it off too long

philipp: what was sent from IG to HTML WG on content protection to date?


clarke: sent along netflix proposal, but not reviewed by group

<bryan> +1 to continuing work on both in parallel - I will seek internal input to provide as feedback

mark_watson: OK with adaptive & content protection in parallel. haven't gotten feedback from group on netflix proposal yet. would like to get feedback.

clarke: Propose content protection for agenda next week.

Model 3 architecture discussion

clarke: Ran into issues with ladder diagram.
... Not clear how model 3 would work, e.g. new MIME type or not. Also not clear how processing would pass to script

<glenn> can't hear markw over background noise on his end

mark_watson: Look at Chrome proposal on Media Source Extension proposal
... script controls content feeding

<glenn> link to "Media Source Extension proposal"??

bob_lund: Problem selecting among alternative media.

mark_watson: Current Chrome model is all decisions in script, not media element

<kaz> ADR Error Codes

jason: The use case of script able to pass segments is agnostic.

duncan: Problem with both approaches - more script control requires more query to engine.

mark_watson: That can mostly be handled by canPlayType
... usage of codec parameters can handle most cases, there may be some corner cases, e.g. limited support for interlace

clarke: duncan's proposal has 3 APIs: appendVideo, currentSegmentDownload [scribe: what was 3rd?]

<franck> http://www.w3.org/2011/webtv/wiki/MPTF/HTML_adaptive_calls

mark_watson: need to generalize appendVideo API to allow placement other than next in sequence

jason: what about a sliding window in live or simulcast? how is anchor maintained?

mark_watson: Not worked out live fully, but need ability to place segments in time line.

clarke: Another example is placing ads within a program

bob: Agree key is to use timeline in media.

Kilroy: There are difficulties with splicing, e.g. if lengths of media segments don't line up. API to support such splicing can get complex.
... Concatenating use case OK, splicing gets more complex.

jason: HLS use case is usually simple concatenation.

kilroy: Script needs to know if streaming engine can handle splicing issues like padding for iframes.
... API needs to differentiate between concatenating vs. complex splicing.
... Segment formats can have constraints that allow for simple concatenation.
... Work on this going on in DASH and other groups. Would rather present consensus than own opinion.

clarke: Has DASH resolved this?

kilroy: DASH work on this still in progress, interacting with several API groups and the several media formats: h264, DASH, etc.

clarke: How do we make a proposal in this area?

mav: Shall we take adaptive & content protection off of HTML5 LC bugs from WebTV IG?
... Suggest Mark Watson decide on whether to withdraw Netflix proposal from LC bug

clarke: Other agenda items?

bob_lund: bug 13359 discussion


bob: I made a proposal submitted for passing data from media stream to script. There's been some push back as complex. There's been some suggestions for simplification.
... I think we'll get something, but not clear what it will be.

bob: I encourage others to comment.

clarke: adjourn

Summary of Action Items

[End of minutes]

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$Date: 2012/02/02 17:17:35 $