AudioCodes Mediant 3000 User Manual page 222

Note: As the main factor (algorithm) for detecting human and machine is the voice
pattern and silence duration, the language on which the detection algorithm is based,
is in most cases not important as these factors are similar across most languages.
Therefore, the default, pre-installed AMD Sensitivity file, which is based on North
American English, may suffice your deployment even if the device is located in a
region where a language other than English is used.
However, if (despite the information stated in the note above) you wish to implement AMD
in a different language or region or if you wish to fine-tune the default AMD algorithms to
suit your specific deployment, please contact your AudioCodes sales representative for
more information on this service. You will be typically required to provide AudioCodes with
a database of recorded voices (calls) in the language on which the device's AMD feature
can base its voice detector algorithms. The data needed for an accurate calibration should
be recorded under the following guidelines:

Statistical accuracy: The number of recorded calls should be as high as possible (at
least 100) and varied. The calls must be made to different people. The calls must be
made in the specific location in which the device's AMD feature is to operate.

Real-life recording: The recordings should simulate real-life answering of a called
person picking up the phone, and without the caller speaking.

Normal environment interferences: The environment in which the recordings are done
should simulate real-life scenarios, in other words, not sterile but not too noisy either.
Interferences, for example, could include background noises of other people talking,
spikes, and car noises.
Once you have provided AudioCodes with your database of recordings, AudioCodes
compiles it into a loadable file. For a brief description of the file format and for installing the
file on the device, see ''AMD Sensitivity File'' on page 696.
The device supports up to eight AMD algorithm suites called Parameter Suites, where each
suite defines a range of detection sensitivity levels. Sensitivity levels refer to how
accurately, based on AudioCodes' voice detection algorithms, the device can detect
whether a human or machine has answered the call. Each level supports a different
detection sensitivity to human and machine. For example, a specific sensitivity level may
be more sensitive to detecting human than machine. In deployments where the likelihood
of a call answered by an answering machine is low, it would be advisable to configure the
device to use a sensitivity level that is more sensitive to human than machine. In addition,
this allows you to tweak your sensitivity to meet local regulatory rules designed to protect
consumers from automatic dialers (where, for example, the consumer picks up the phone
and hears silence). Each suite can support up to 16 sensitivity levels (0 to 15), except for
Parameter Suite 0, which supports up to 8 levels (0 to 7). The default, pre-installed AMD
Sensitivity file, based on North American English, provides the following Parameter Suites:

Parameter Suite 0 (normal sensitivity) - contains 8 sensitivity detection levels

Parameter Suite 1 (high sensitivity) - contains 16 sensitivity detection levels
As Parameter Suite 1 provides a greater range of detection sensitivity levels (i.e., higher
detection resolution), this may be the preferable suite to use in your deployment. The
detected AMD type (human or machine) and success of detecting it correctly are sent in
CDR and Syslog messages. For more information, see ''Syslog Fields for Answering
Machine Detection (AMD)'' on page 799.
The Parameter Suite and sensitivity level can be applied globally for all calls, or for specific
calls using IP Profiles. For enabling AMD and selecting the Parameter Suite and sensitivity
level, see ''Configuring AMD'' on page 224.
The tables below show the success rates of the default, pre-installed AMD Sensitivity file
(based on North American English) for correctly detecting "live" human voice and
answering machine:
User's Manual 222
Mediant 3000
Document #: LTRT-89730