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Re: Detecting time-averaged levels

From: Chris Wilson <cwilso@google.com>
Date: Fri, 3 Aug 2012 15:29:45 -0700
Message-ID: <CAJK2wqVqT+=8P11e1ivaZsomJ-rRcux5z7ddG5-mQBQqXQTXcA@mail.gmail.com>
To: Joseph Berkovitz <joe@noteflight.com>
Cc: Audio Working Group <public-audio@w3.org>
Another way I'd considered doing this was using a DynamicsCompressor node,
cranking up the ratio and cranking down the threshold and knee, adjusting
the attack and release as desired - then the "reduction" property becomes a
convenient sampling of level.

On Fri, Aug 3, 2012 at 12:00 PM, Joseph Berkovitz <joe@noteflight.com>wrote:

> A number of scenarios in the Use Case document require a time-averaged
> level for some audio pathway -- maybe something like an RMS using a rolling
> average of squared signal values.
>
> Anyway, I'm wondering if I have missed any simple way of calculating such
> a level, or whether one must fall back to a JavaScriptAudioNode to do this.
>  It kind of seems natural for a RealtimeAnalyzerNode to do this even though
> it's not frequency-domain data.
>
> Regards,
>
> ... .  .    .       Joe
>
> *Joe Berkovitz*
> President
>
> *Noteflight LLC*
> Boston, Mass.
> phone: +1 978 314 6271
> www.noteflight.com
>
>
Received on Friday, 3 August 2012 22:30:14 GMT

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