[asterisk-dev] DTMF Volume

Tony Redstone tony.redstone at googlemail.com
Thu Jul 3 08:23:13 CDT 2008


Hi,

On Wed, Jul 2, 2008 at 7:00 PM, Konstantin Bokarius
<bokarius at comcast.net> wrote:
[cut]
> When I tried to change that value to a negative, low (1-10), or very high
> number I did not notice any change with the DTMF volume.
>
> Are there other values that need to be changed – or am I missing something?

The function you are looking it is for inserting real DTMF tones into
the audio stream.  However, you've already said you're using rfc2833
so you want to be looking at the ast_rtp_senddigit_*() functions in
main/rtp.c instead.

In each of the three senddigit functions, the value is set within the
rtpheader[3]=... line.
eg
    rtpheader[3] = htonl((rtp->send_digit << 24) | (0xa << 16) |
(rtp->send_duration));

The volume is the 0xa value.  You need to increase this value to
reduce DTMF volume.  I'm sure it goes without saying but read rfc2833
to find out more regarding what the volume values correspond to.

Hope this helps

Regards,
Tony



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