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Re: Is Web Audio a realtime API?

From: Chris Lilley <chris@w3.org>
Date: Wed, 14 Jan 2015 18:02:11 +0100
Message-ID: <1310721299.20150114180211@w3.org>
To: Oleg Beletski <o.beletski@samsung.com>
CC: "public-audio@w3c.org" <public-audio@w3c.org>
Hello Oleg,

Wednesday, January 14, 2015, 3:11:56 PM, you wrote:

> Specification lists performance and latency considerations, but
> does not explicitly state if API is realtime or not.

That depends on your definition of realtime.

On the one hand, it concerns audio which is generated "in realtime"
rather than previously recorded audio which is merely played back.

On the other hand, it will almost always be executed on a
non-realtime, multitasking OS rather than a RTOS. And audio samples
are processed in blocks rather than as individual samples, so
sample-accurate sync is hard (128 samples at 44.1k is 2.9ms).

Best regards,
 Chris Lilley, Technical Director, W3C Interaction Domain
Received on Wednesday, 14 January 2015 17:02:15 UTC

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