lkml.org 
[lkml]   [2003]   [Jan]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [Asterisk] DTMF noise
Date
Wolfgang Fritz wrote:

[cut]

>
> There exists a long text about DTMF detection somewhere on the net (I
> may have the link in the office but I'm on vacation now). What I
> remember is that a "correct" DTMF detection requires much more computing
> power as the present i4l implementation needs (much longer audio samples
> for the goertzel filter, a larger number of frequencies to check) and a
> standard test procedure with a lot of test cases which are not available
> to mortal humans (audio tapes from Bellcore IIRC)
>

The link below is not the text I mean above but shows an approach which
is similar to the present i4l implementation but has some improvements
which may be good enough for us.

http://www.mitsubishichips.com/press/dtmf0199e.pdf

> Wolfgang
> >
[cut]




-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:32    [W:0.106 / U:0.668 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site