[PD] detect silence

[Dario Sanfilippo]

If you want to work in the audio domain, consider calculating the RMS by
simply squaring, low-passing, and taking the sqrt of the signal. The cutoff
determines your averaging window.

You can implement relational operators in the audio domain by using [/~],
as the same signal connected to both of its inputs will give 0 when the
signal is 0, and 1 otherwise. There was a nice conversation on the PD
facebook group on this. Thanks to Matt Barber.

For example:

[inlet~] [inlet~]
| \          |
|   \        |
|     \      |
|    [max~]
|     /
[-~   ]
|    \
[/~   ]
|
[outlet~]

is [<~].

You can then use a lowpass to slow down the transitions between true or
false. The impulse response of [rpole~] will decrease of ~60dB (1/1024) in
a desired time by setting the feedback coefficient B with B = .001^t/T60. t
is the feedback period N/Fc and T60 is the decay time in sec. [rpole~] is
an IIR but it will truncate to 0 when its output gets very small.
Approximately, using the formula above, it will get to 0 after a desired
time if you multiply the decay time by .158065.

Cheers,
D

On 9 September 2016 at 07:47, enrike <altern2 at gmail.com> wrote:

> thanks Jaime. I was checking fiddle~ and bonk~ but I guess env~ goes more
> to the point.
>
> og., 2016.eko iraren 08a 18:08(e)an, Jaime Oliver igorleak idatzi zuen:
>
> env~ should help you do that.
>>
>> J
>>
>>
>>
>> On Sep 8, 2016, at 9:01 AM, enrike <altern2 at gmail.com> wrote:
>>>
>>> hi all
>>>
>>> is there any abstraction or external that allows to detect silence in
>>> the sound in? I mean if the amplitude drops below a threshold for a given
>>> period of time.
>>>
>>> I was thinking about how to get this going to try to build it myself
>>> then I thought there might be some external or abstraction that already
>>> does what I need. Tired of reinventing the wheel...
>>>
>>> thanks
>>>
>>> enrike
>>>
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>>
>>
>>
>
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