Subject: RE:

From: [email-masked]
Date: Thu, 31 Dec 1998 15:28:36 -0500

Hello,

The most commonly accepted measure of Voice Quality associated
with VoIP is the Mean Opinion Score. In this measurement system,
POTS (regular phone) is considered a 4. G.723.1 comes in at 3.98.
Anything above 3.5 is considered acceptable.

More information can probably be found at sites of companies that
license DSP code for encoding voice ... e.g. the DSP Group at
http://www.dspg.com

Best Regards,

- Greg Boop
   Mgr - VoIP Development
   IBM - NHD
   RTP, NC, USA
   Phone: +1 919 254 0319
   [email-masked]

"Noah, Matt" <[email-masked]> on 12/30/98 12:00:48 PM

To:   "[email-masked]'"
      <[email-masked]>,
      [email-masked]
cc:    (bcc: Gregory Boop/Raleigh/IBM)
Subject:  RE:

"Clarity" is a subjective term.  It most closely approximates, IMO, a term
known as "intelligibility".  The military has used the DRT and DAM tests
for quantifying speech quality.  The DRT - Diagnostic Rhyme Test - and
DAM - Diagnostic Acceptability Measure - are the 2 tests most often
used.  There are companies which will perform these tests on speech
databases for you for a fee.

> -----Original Message-----
> From:   [email-masked]
[SMTP:[email-masked]]
> Sent:   Tuesday, December 29, 1998 8:59 AM
> To:     [email-masked]
> Subject:
>
>      All:
>
>      We are trying to specify the "clarity" of voice links in a military
>      system.  Is there a method (or ISO spec?) for specifing voice
quality?
>
>      If this is not the right mailing list for this type of problem,
could
>      someone please point me to the correct one?
>
>      thanks
>      [email-masked]
> ---------
> This message came from the IETF IPTEL Working Group Mailing List.
---------
This message came from the IETF IPTEL Working Group Mailing List.

---------
This message came from the IETF IPTEL Working Group Mailing List.