[asterisk-users] how asterisk detects silence?

[Matthew Jordan]

On Mon, Mar 23, 2015 at 12:25 AM, Dmitry Melekhov <dm at belkam.com> wrote:
> 19.03.2015 09:31, Dmitry Melekhov пишет:
>>
>> Hello!
>>
>> As I see there is  dsp_drop_silence switch in confbridge.
>> Could you tell me how asterisk detects silence?
>> Is it possible to change silence level,
>> so, let's say some not loud enough background noises will be recognized as
>> silence
>> and only loud enough human voice will be recognized as sound?
>>
>> Thank you!
>>

Asterisk passes received voice data, converted to signed linear,
through a DSP. The DSP looks at the energy level in the data and, if
it is above a certain value, categorizes the data as 'silence' or
'talking'.

You can tweak the periods necessary for Asterisk to decide if someone
is talking or silent using the 'dsp_silence_threshold' and
'dsp_talking_threshold' settings:

https://wiki.asterisk.org/wiki/display/AST/Asterisk+13+Configuration_app_confbridge

-- 
Matthew Jordan
Digium, Inc. | Director of Technology
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at: http://digium.com & http://asterisk.org