Audio Working Group Teleconference -- 19 Dec 2013

<trackbot> Date: 19 December 2013

<scribe> Meeting: Audio Working Group Teleconference

Date: 19 December 2013

<scribe> Agenda: http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0330.html

<scribe> Chair: olivier

<cwilso> grr

<cwilso> sigh.

<padenot> is the quality terrible today, or am I having problems?

<cwilso> jmd = Janet Dunbar

zakim take up agendum 1

Review of action items

<scribe> Agenda: http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0330.html

<padenot> gahh, skype crashed on me, one sec

ACTION-87

<trackbot> ACTION-87 -- Matthew Paradis to Review http://docs.webplatform.org/wiki/apis/webaudio, suggest updates -- due 2013-12-12 -- OPEN

<trackbot> http://www.w3.org/2011/audio/track/actions/87

ACTION-91

<trackbot> ACTION-91 -- Chris Wilson to Do a quick review of hrt l2 -- due 2013-12-12 -- PENDINGREVIEW

<trackbot> http://www.w3.org/2011/audio/track/actions/91

cwilso: went through spec
... very little new. adding support to workers
... only one substantial change - more clearly defined origin

action-91 closed

<trackbot> Closed action-91.

action-89

<trackbot> action-89 -- Paul Adenot to Look at current implementations, and draft interface to request mathematical oscillator (issues/127) and specify phase (base on pr 270) -- due 2013-12-12 -- OPEN

<trackbot> http://www.w3.org/2011/audio/track/actions/89

padenot: hoping to have a PR by tomorrow

ACTION-89 due in 3 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 2014-01-09.

action-80

<trackbot> action-80 -- Chris Wilson to Remove webaudio section on example applications, photos from section on convolution, and salvage anything valuable -- due 2014-01-09 -- OPEN

<trackbot> http://www.w3.org/2011/audio/track/actions/80

cwilso: at the top of my audio pile

ACTION-80 due in 3 weeks

<trackbot> Set ACTION-80 Remove webaudio section on example applications, photos from section on convolution, and salvage anything valuable due date to 2014-01-09.

action-86

<trackbot> action-86 -- Chris Lowis to Document the case of mediaelementaudiosource and mediastreamaudiosource nodes in offlineaudiocontext on github -- due 2013-12-19 -- OPEN

<trackbot> http://www.w3.org/2011/audio/track/actions/86

De-zippering

http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0329.html

look at http://lists.w3.org/Archives/Public/public-audio/2013OctDec/0322.html for point 3 of the CfC

on how to define the smoothing

Agreement on this?

“I expect we can come up with a similar mathematical function or

functions to those involved in AudioParam methods, but the

parameters are different because AudioParam methods are designed

for scheduling effects in the future. We don't have a good way to

specify the start time to be "as soon as possible" or to specify

the duration of the transition.

[group reading the suggestion from Karl on how we'd define dezippering not as one of the current methods

]

cwilso: seems to be a very different approach to smoothing
... I had understood that as "whenever you set .value you effectively use settargetattime”
... I believe Karl is thinking of how you'd smooth different things
... gets complicated if you have to start doing a whole inventory
... created https://github.com/WebAudio/web-audio-api/issues/279
... as a byproduct of this discussion

olivier: so should it be strictly defined as an alias of settargetattime or leave it to implementation?

cwilso: would be opposed to leaving it to implementation
... could create too significant incompatibilities

padenot: agree

cwilso: would be inclined to define as alias
... under the hood it is effectively calling settargetattime
... clarify the parameters
... so it's very precise
... and explicitely list which ones it does not apply to
... and clarify the use of setvalueattime if you don't want smoothing

olivier: how about AudioBufferSourceNode.playbackRate and OscillatorNode.frequency ?

padenot: no reason not to do that
... it doesn't cause problem if you change them immediately

olivier: the discussion is not about what is the best, but about consistency

shepazu: agreed. there seems to be consensus
... my only worry is if there was strong opposition between implementors

olivier: having had the CFC and clarifying discussion

RESOLUTION: smoothing by default on all audioparam when setting .value, essentially an alias to settargetvalueattime, time constants TBD

Data Races

- https://github.com/WebAudio/web-audio-api/issues/66 (AudioBuffer, assigned, needs PR)

- https://github.com/WebAudio/web-audio-api/issues/268 (AudioProcessingEvent, TBD, on ChrisW’s pile)

- https://github.com/WebAudio/web-audio-api/issues/254 (The rest. There seems to be consensus. I want to assess that and move on)

olivier: first one (github-66) is on your pile now that refactoring done?

padenot: it's landed

<padenot> http://padenot.github.io/web-audio-api/#the-audiobuffer-interface + http://padenot.github.io/web-audio-api/#audio-buffer-copying

olivier: can you connect the PR to issue-66
... https://github.com/WebAudio/web-audio-api/issues/268
... on your pile cwilso. Any ETA?

cwilso: ETA end of January
... biggest concern with Paul's proposal is I'm unsure about performance cost
... agree we need to make it so the modification outside of callback doesn't have any effect

olivier: want to spend some time looking at impact

cwilso: tends to be heavy already
... might only be a small impact

<scribe> ACTION: cwilso to report on exploration of performance impact of github issue 268 [recorded in http://www.w3.org/2013/12/19-audio-minutes.html#action01]

<trackbot> Created ACTION-92 - Report on exploration of performance impact of github issue 268 [on Chris Wilson - due 2013-12-26].

action-92 due 2014-01-28

<trackbot> Set action-92 Report on exploration of performance impact of github issue 268 due date to 2014-01-28.

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

olivier: looking at comment https://github.com/WebAudio/web-audio-api/issues/254#issuecomment-26590612

<padenot> sorry, crashed again

olivier: do I understand there is consensus on the remaining 3

cwilso: yes. think we already do copy
... need to check. what paul wrote seems like the right way
... ok to make changes, don't think we need to investigate before deciding what the right thing

<scribe> ACTION: Padenot to implement changes listed in https://github.com/WebAudio/web-audio-api/issues/254 [recorded in http://www.w3.org/2013/12/19-audio-minutes.html#action02]

<trackbot> Created ACTION-93 - Implement changes listed in https://github.com/webaudio/web-audio-api/issues/254 [on Paul Adenot - due 2013-12-26].

action-93 due in 4 weeks

<trackbot> Set action-93 Implement changes listed in https://github.com/webaudio/web-audio-api/issues/254 due date to 2014-01-16.

annotations

shepazu: looking into annotations
... highlight section of a webpage and leave comments
... think we could benefit from this feedback mechanism
... and improve w3c feedback
... working with a nonprofit called hypothesis
... about to start an experiment with our specs in this group
... to provide feedback by annotating the spec
... maybe some time in Jan

olivier: next meeting 16th Jan

- DRAFT -

Audio Working Group Teleconference

19 Dec 2013

Attendees

Contents

Review of action items

De-zippering

Data Races

annotations

Summary of Action Items

Scribe.perl diagnostic output