Audio WG Teleconference -- 25 Apr 2012

<Gabriel> was fast

<olivier> Scribe: Jer

shepazu: (gives jernoble a brief introduction to scribe-taking)

Review of web audio API ED changes

<olivier> Agenda: http://lists.w3.org/Archives/Public/public-audio/2012AprJun/0069.html

<olivier> http://lists.w3.org/Archives/Public/public-audio/2012AprJun/0068.html

olivier: call for comments and questions about recent changes to the WebAudio API

(no comments or questions)

Channel handling (ISSUE-9)

<olivier> ISSUE-9?

<trackbot> ISSUE-9 -- Multi-Channel support in Use Cases & Reqs. -- open

<trackbot> http://www.w3.org/2011/audio/track/issues/9

chris: an introduction to how multichannel audio is dealt with in the WebAudio API

… WebKit implementation assumes stereo output, irrespective of hardware channel support

… may need to add a new API in the AudioContext (either in the constructor or later) to query for hardware channel support

olivier: issue surrounding javascript node and a single channel input and output; the WebKit implementation assumes stereo in and out

chris: not intentional. results are due to a bug in webkit which may be recently fixed

… number of output channels on a javascript node were previously ignored; now fixed

scribe: another bug where the number of input nodes is also being ignored; will also soon be fixed.

Use Cases and Deployment Document

olivier: document only mentions number of channels in one use case; specifically mixing multiple channels into one

… would there be value in adding to one of our use cases to a) handle >2 channels as output and b) ability to down mix to 2 channels regardless of hardware support for >2 channels.

chris: has no objection to adding those use cases.

olivier: use cases section of document is not normative (??) so adding prospective use cases is fine

Gain negative or above 1 (ISSUE-10)

<olivier> ISSUE-10

<olivier> ISSUE-10?

<trackbot> ISSUE-10 -- Negative values suggested for the Audio Gain Node -- pending review

<trackbot> http://www.w3.org/2011/audio/track/issues/10

olivier: Issue was pretty much solved: talked about last week, and a spec change resulted.
... call for further comments or questions about the spec change.

(no comments or questions)

<olivier> RESOLVED: change to the API satisfying ISSUE-10, can close

Offline audio context (ISSUE-11)

<olivier> ISSUE-11?

<trackbot> ISSUE-11 -- Offline Audio Context -- open

<trackbot> http://www.w3.org/2011/audio/track/issues/11

chris: this still needs to be added to the spec; will add it soon.

olivier: is there any controversy about this change?

chris: not really. work is ongoing in the WebKit implementation. will add to the spec in the next few days.

joe: this is an important feature for a number of use cases; would like to see it added to the spec.

olivier: this has been documented in at least one of the use cases. agreed that it is important.

midi and charter

shepazu: propose that we add MIDI to the charter

olivier: seems to remember that cwilso already added this to the charter

<shepazu> http://lists.w3.org/Archives/Public/public-audio/2012JanMar/0290.html

<joe> Some user agents have connected music devices, such as synthesizers, keyboard controllers and drum machines. The widely adopted MIDI protocol enables electronic musical instruments, controllers and computers to communicate and synchronize with each other. MIDI does not transmit audio signals: instead, it sends event messages about musical notes, controller signals for parameters such as volume, vibrato and panning, cues and clock signals to set the tempo, and sys

shepazu: will go forward with updating the charter.

<olivier> RESOLVED: charter will be updated with Chris Wilson's proposed wording from Feb 27th

- DRAFT -

Audio WG Teleconference

25 Apr 2012

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