W3C

- DRAFT -

Audio Working Group Teleconference

06 Feb 2014

Agenda

See also: IRC log

Attendees

Present
padenot, olivier, cwilso, Doug_Schepers
Regrets
Chair
olivier
Scribe
olivier

Contents


<trackbot> Date: 06 February 2014

Review of action items

http://www.w3.org/2011/audio/track/agenda

ACTION-70 closed

<trackbot> Closed ACTION-70.

action-80 due in 2 weeks

<trackbot> Set action-80 Remove webaudio section on example applications, photos from section on convolution, and salvage anything valuable due date to 2014-02-20.

action-81 due in 2 weeks

<trackbot> Set action-81 Contact tag, point them to tag issues in github, continue conversation there due date to 2014-02-20.

action-86 due in 2 weeks

<trackbot> Set action-86 Document the case of mediaelementaudiosource and mediastreamaudiosource nodes in offlineaudiocontext on github due date to 2014-02-20.

action-89 - ongoing

padenot: I have a spec draft for this
... and for the phase too

spec'd in terms of odd function with an upward slope

padenot: not mathematical formulas

action-89 due in 2 weeks

<trackbot> Set action-89 Look at current implementations, and draft interface to request mathematical oscillator (issues/127) and specify phase (base on pr 270) due date to 2014-02-20.

action-90: ongoing... the github issue has solution

<trackbot> Notes added to action-90 Look into https://github.com/webaudio/web-audio-api/issues/15 - assess how complex the change would be (and ideally suggest pr to spec).

action-90: the actual patch remains to be added to the spec

<trackbot> Notes added to action-90 Look into https://github.com/webaudio/web-audio-api/issues/15 - assess how complex the change would be (and ideally suggest pr to spec).

action-90 due in 2 weeks

<trackbot> Set action-90 Look into https://github.com/webaudio/web-audio-api/issues/15 - assess how complex the change would be (and ideally suggest pr to spec) due date to 2014-02-20.

action-92: cwilso says he has looked into it with Ray and Alex. Should be doable but makes the problem with scriptprocessor even worse

<trackbot> Notes added to action-92 Report on exploration of performance impact of github issue 268.

cwilso: we really need to come up with worker scriptprocessor sooner rather than later
... open to other inputs, but that is current thinking

olivier: what's stopping us from doing worker scriptprocessornode, other than complexity / time consuming

cwilso: may be hard to deploy across platforms

olivier: don't remember if we'd wanted to keep them out of scope for v1

cwilso: CRogers wanted to do something better than workers IIRC

olivier: I actually recall this was in scope and assigned to CRogers, but never touched... probably because it is challenging/imperfect

padenot: we need a solution - lots of demand for scriptprocessor node, and it doesn't do what people want
... as currently spec'd, it will glitch.
... feedback from game devs was negative
... we have some workarounds in gecko, not quite good enough

cwilso: good idea to get padenot, ROC and cwilso to sketch a solution

padenot: timezone might make it hard
... I could ask ROC to summarise, and then you and me sketch a solution?

<GitHubBot> [web-midi-api] toyoshim opened pull request #97: size attribute must be unsigned long (gh-pages...ul_size) https://github.com/WebAudio/web-midi-api/pull/97

olivier: worth thinking about including Alex/TAG in discussion at some point, without going full-on design by committee

action-92 due in 2 weeks

<trackbot> Set action-92 Report on exploration of performance impact of github issue 268 due date to 2014-02-20.

action-93 closed

<trackbot> Closed action-93.

see https://github.com/webaudio/web-audio-api/issues/254

Dezippering

objections voiced by KarlT -> http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0340.html

cwilso: was confused by the objection on delaytime, sounds like a bug

http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0335.html

<cwilso> http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0339.html

cwilso: sounds like implementation bug

olivier: confused - we did discuss this and chose consistency over choosing a "best" behaviour for every possible parameter
... and try to be "nicer" to less-advanced developers

cwilso: need to separate the issue of implementation bug with setValueAtTime/delayTime with question of default behaviour

olivier: we still need to address http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0340.html

cwilso: [looking in spec]
... interestingly, it appears that we have computed values as well as intrinsic values
... not clear to me what the getter is supposed to return
... “When read, the value attribute always returns the intrinsic value for the current time”
... so karl's point is valid

-> http://www.w3.org/TR/webaudio/#computedValue-AudioParam-section

cwilso: points are correct and the cost of having automatic dezippering
... in either case a knowledgeable developer can fix the problem

olivier: how about better documentation of .value in http://www.w3.org/TR/webaudio/#AudioParam
... better explain .value both as setter and getter

cwilso: yes we need to better document it, especially for things like gainnode if we remove dezippering

olivier: understand this is a cost of dezippering. If everyone understands the cost and it is well documented, then it does not seem to pose a strong challenge to the decision?

cwilso: to be fair to Karl we probably don't understand the cost all too well
... ultimately we're going to add work for advanced developers, or get bad quality for naive developers
... cwilso: would be simpler to not do dezippering
... also cost of removing it today for existing code

olivier: difficult to decide between making it easy for novice devs or making sure they learn faster
... given that the two choices are almost equivalent in pain/gain, tempted by status quo
... (implementation status quo)

Cross-origin media requests

http://lists.w3.org/Archives/Public/public-audio/2013JulSep/0219.html

http://lists.w3.org/Archives/Public/public-audio/2014JanMar/0035.html

padenot: shouldn't allow inspection of cross-origin media using web audio
... possible ATM in blink and webkit
... you can e.g. do speech recog of cross-origin media
... proposal we have is that if media is cross-origin and cross-origin request not allowed, media should play as it does today, but if it goes into web audio, it should be muted
... similar to canvas

cwilso: [thoughtful grunt]
... concerned that it would stop people doing simple things
... but it does sounds reasonable

olivier: would it make sense to throw exception in addition to muting?

padenot: we just log a message in the dev tools

Resolution: tentative consensus around https://github.com/webaudio/web-audio-api/issues/282 - olivier to send formal CfC alongside minutes, ends in a week

next teleconference

20th February 2014, same time

Summary of Action Items

[End of minutes]

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Default Present: padenot, olivier, cwilso, Doug_Schepers
Present: padenot olivier cwilso Doug_Schepers
Agenda: http://lists.w3.org/Archives/Public/public-audio/2014JanMar/0066.html
Found Date: 06 Feb 2014
Guessing minutes URL: http://www.w3.org/2014/02/06-audio-minutes.html
People with action items: 

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