Media Pipeline Task Force Teleconference

29 Mar 2012


See also: IRC log


Glenn, Clarke, Dave, Philipp, Joe, Duncan, Franck, Kevin, Jason, Kazuyuki, Mark_Vickers, Juhani(?), Mark_Watson, Paul


<Clarke> ABR proposal: http://html5-mediasource-api.googlecode.com/svn/trunk/draft-spec/mediasource-draft-spec.html

<Mark_Vickers> It would be good to put the GoToMeeting info on the Logistics page.

Encrypted Media TF of the HTML WG

<glenn> i will ask at the upcoming HTML WG meeting in an hour

<kaz> HTML public list discussion

<inserted> scribenick: franck

adaptive bit rate proposal (Media Source extension)

<kaz> proposal v0.4

mw: discussing segment switching, required to be on SAP


Dicussing requirement 3:

Any challenges with trick play?

CS: Req 4: using canPlayType or other means...
... improvement for interop if canPlayType could provide more info

<kaz> i|Discussing requirement 3:|-> http://www.w3.org/2011/webtv/wiki/MPTF#Adaptive_Bit-Rate_Control_in_Script_.28model_3.29 ABR Requirements|

MW: mimeType provide info on codecs
... 2nd would be info on container format in use
... If your player support these both types, should be OK
... examples on different mp4 boxes organization: should it be exposed?

MV: could MPEG-2 TS can be used ?

CS: next requirement 5 on no advantage for a method aver another
... combination of codecs/file formats

MW: discussing segment switching between Apple HLS and DASH segments

CS: people implementing HLS put the burden on the client, would be good to have feedback from HLS people

Req 6: "must work with open source browsers"

CS: make sure that open source browser can use this method to do ABR
... if we focus on unencrypted content, try to keep content protection elsewhere, req 6 should be fulfilled ?
... Mark, any opinion ?

<kaz> ACTION: Stevens to ping D. Singer on requirement 5 [recorded in http://www.w3.org/2012/03/29-webtv-minutes.html#action02]

<trackbot> Created ACTION-97 - Ping D. Singer on requirement 5 [on Clarke Stevens - due 2012-04-05].

MW: ask Chrome guys

CS: content protection: is there anything that would prevent open source browser to implement ABR with a proprietary decryption part ?

MW: need to make sure that jscript will be able to access segment info and timing info
... ...independently from how it has been encrypted

CS: next requirement 7: "ABR media must be useable in HTML5"
... no specific comment
... Req 8: (linked to Req4), content must be identifiable

MW: HLS/DASH, which profile, or whatever, would be handled by the script, thus does not apply to media source extension

CS: should we change wording for this req?
... ... and review next time
... Req 9: identifiable parameters
... pass info through mime type and mime parameters: is it sufficient?

MW: seems yes

CS: Req 10: error reporting
... need for new errors ?

MW: none provided yet

CS: any errors needed to communicate back to the media element?

MW: talking about browser doing the fetching itself , instead of XHR
... some interactions there, maybe with errors ?

CS: We'll assume it's OK and somebody to speak if not

MV: case where splicing ad into the media: ?

MW: use another media element to render the ad

MV: add this use case as a requirement: how to properly handle this (ad insertion impact on presentation timeline)

CS: Please provide text on the wiki


MW: you would need some changes in the API to perform this use case

MV: look at it carefully

CS: Useful to have best practises ?
... any additional reqs?
... open item: document to provide to HTML TF, should be ready in 1-2 calls

<kaz> [ adjourned ]

<Clarke> Thanks Franck

<kaz> thanks, franck!


Summary of Action Items

[NEW] ACTION: Stevens to ping D. Singer on requirement 5 [recorded in http://www.w3.org/2012/03/29-webtv-minutes.html#action01]
[End of minutes]

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$Date: 2012/03/29 16:07:47 $