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Re: specific demos wanted, question about media streams processing api

From: Samuel Goldszmidt <samuel.goldszmidt@ircam.fr>
Date: Mon, 26 Mar 2012 10:33:10 +0200
Message-ID: <4F7029C6.9050006@ircam.fr>
To: public-audio@w3.org
Robert, thanks for your answers,
For my second point, "Offline processing" was a wrong term, I mean, 
reada soundfile faster than real-time
to build a temporal waveform visualization, like the ones we have in 
soundcloud for instance.



Le 26/03/12 05:08, Robert O'Callahan a écrit :
> On Fri, Mar 23, 2012 at 11:23 PM, Samuel Goldszmidt 
> <samuel.goldszmidt@ircam.fr <mailto:samuel.goldszmidt@ircam.fr>> wrote:
>     - full fft implementation in javascript (is this one up to date ?
>     https://wiki.mozilla.org/Audio_Data_API)
>     - full convolution engine implementation in javascript too.
>     using both of the 2 apis ( Web audio api and media streams
>     processing api)
> I haven't ported any Audio Data FFT or convolution examples to 
> MediaStreams but it wouldn't be hard.
>     - a sort of offline processing with media streams processing api,
>     to represent waveform (I know with the comparison of the 2 api in
>     the wiki, that "offline" processing in media streams could be more
>     difficult to achieve, that's why I'm looking for this kind of demo)
> I'm not quite sure what you mean by "offline processing". I think you 
> probably mean the ability to construct a stream graph and drive it at 
> the maximum possible speed to record a composition or something like that.
> As far as I can tell, neither Web Audio or MediaStreams Processing 
> supports that currently. (The comparison wiki page 
> http://www.w3.org/2011/audio/wiki/Spec_Differences says Web Audio 
> does, but I don't see API for it on AudioContext in 
> https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#AudioContext-section.)
> I think there's nothing difficult in principle about adding API for 
> this to either proposal. Since MediaStreams Processing doesn't have a 
> context object, I would just add an API to MediaStream that controls 
> the processing rate of the entire connected subgraph.
> Rob
> -- 
> “You have heard that it was said, ‘Love your neighbor and hate your 
> enemy.’ But I tell you, love your enemies and pray for those who 
> persecute you, that you may be children of your Father in heaven. ... 
> If you love those who love you, what reward will you get? Are not even 
> the tax collectors doing that? And if you greet only your own people, 
> what are you doing more than others?" [Matthew 5:43-47]
Received on Monday, 26 March 2012 08:33:47 UTC

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