[PD] Detect silence inArray and resize

Frank Barknecht fbar at footils.org
Sun Apr 4 11:40:38 CEST 2010


On Sun, Apr 04, 2010 at 10:56:54AM +0200, Matteo Sisti Sette wrote:
> > anyone have any idea how to do this?
>
> The first approach that comes to my mind and that I would try is:
>
> - use [env~] (or anything similar) to measure the amplitude of the signal
>
> - start a [timer] when you start recording
>
> - set TWO thresholds: one high threshold to detect when the "note" has  
> begun (attack) and a low threshold to detect that it has finished.
>
> - Only after the signal amplitude has become greater than the HIGH  
> threshold _and_ when it becomes again lower than the LOW threshold, then  
> you fire the right inlet of the [timer] to measure the time passed since  
> the beginning: you multiply by the sampling rate and you obtain the size.
>
>
> That is, you have to emulate the behaviour of a [threshold~] object and  
> use its "rest" bang (see threshold help patch).
> Since you're probably gonna use [env~] you cannot actually use  
> [threshold~] but it's very easy to emulate its behaviour (at least  
> simplified as described here which is enough for this purpose).

You could use the [m_thresholds] abstractions in the rj-library here.

Ciao
-- 
Frank




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