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Re: Added direct JavaScript processing to WebKit prototype

From: Chris Marrin <cmarrin@apple.com>
Date: Fri, 06 Aug 2010 14:47:09 -0700
Cc: public-xg-audio@w3.org, Corban Brook <corbanbrook@gmail.com>
Message-id: <E98F77D8-FF4A-448B-8173-EB4306D9C033@apple.com>
To: Chris Rogers <crogers@google.com>

On Aug 6, 2010, at 2:42 PM, Chris Rogers wrote:

> > This demo is pretty simple, but I'd be very interested in porting some of the Mozilla demos to this API.  Corban, would it be OK with you if I ported some of your demos which use the DSP.js library you've been working on?
> 
> Very nice. Overhead on my machine is very low (20%) and I think at least half that overhead is WebGL rendering. It would be nice to duplicate the functionality of the Realtime Ananyzer demo so we can understand the difference in overhead between doing FFT's in JS vs native code.
> 
> -----
> ~Chris
> cmarrin@apple.com
> 
> Sure, I can do that.  I know that the Mozilla folks have already done this and found the JS FFT performance to be acceptable for realtime analysis.  Where the FFT overhead gets quite a lot heavier is in panning/spatialization and convolution where there are hundreds of larger sized FFTs per second.

It would be useful to have an apples-to-apples comparison. What sample rate does the Realtime Analyzer demo use? It would be nice to do a test of 48KHz stereo, just to see how much we can stress it in JS.

-----
~Chris
cmarrin@apple.com
Received on Friday, 6 August 2010 21:47:42 GMT

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