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Re: fftSize requirement for RealtimeAnalyserNode

From: Jussi Kalliokoski <jussi.kalliokoski@gmail.com>
Date: Thu, 22 Mar 2012 13:07:46 +0200
Message-ID: <CAJhzemWzrL+zGNnSYabYThHGLCH3iRG0=uin3KtTp+P5QhTmrQ@mail.gmail.com>
To: "Wei, James" <james.wei@intel.com>
Cc: "public-audio@w3.org" <public-audio@w3.org>
I hadn't actually even noticed this. Interesting. Why exactly should the
value be a power of two? It seems to me like the spec shouldn't say
something like this. Sure, power of two FFTs are easier to implement than
others, but IIRC they are rarely the fastest. And if we aim for
performance, the implementation should probably be using something like
FFTW that allows for any buffer size anyway.

Cheers,
Jussi

On Thu, Mar 22, 2012 at 11:02 AM, Wei, James <james.wei@intel.com> wrote:

>  ** **
>
> For fftSize in RealtimeAnalyserNode in the spec, it only says the value
> must be power of 2.****
>
> ** **
>
> But in fact in the implementation, the value must be limited in the range
> of [128, 2048], and it will throw the exception if illegal value of fftSize
> is set.****
>
> ** **
>
> Which should be documented in the spec. ** **
>
> ** **
>
> ** **
>
> Best Regards ****
>
> ** **
>
> James ****
>
> ** **
>
> ** **
>
Received on Thursday, 22 March 2012 11:08:18 GMT

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