HMP Linux 1.2 Release Update, Rev 05 — September 2006September 2006 30
3.4 Development Software Documentation
This section contains updates to the following documents:
Audio Conferencing API for Linux and Windows Operating Systems Library Reference
Audio Conferencing API for Linux Operating Systems Programming Guide
Continuous Speech Processing API for Linux and Windows Operating Systems
Library Reference
Global Call IP for Host Media Processing Technology Guide
Voice API for Host Media Processing Library Reference
Voice API for Host Media Processing Programming Guide

3.4.1 Audio Conferencing API for Linux and Windows Operating

Systems Library Reference

Update to dcb_getbrdparm( ) and dcb_setbrdparm( ) functions (IPY00006584 = PTR
36199)
Changed the description of the MSG_ACTID parameter to indicate that it
enables/disables active talker identification (or notification) and not the active talker
feature itself. Replace the MSG_ACTID parameter with the following:
Enables or disables Active Talker Identification (or Notification). Possible values are
ACTID_ON or ACTID_OFF. ACTID_ON is the default. This parameter does not enable or
disable the active talker feature, which is always enabled. It only disables the notification to
the application program. The active talker feature sums the 3 most active talkers in a
conference, so that the conversation doesn’t get drowned out when too many people talk at
once. Active talker notification provides data on active talkers through the dcb_gettalkers()
and dcb_GetAtiBitsEx() function s, which can be used by an application program to identify
active talkers; for example, to provide a visual display highlighting the active talkers in a
conference. Active talkers are determined by their loudness; i.e., the strength of their “non-
silence” energy.
Note: In some cases, it is desirable to inactivate the active talker feature, such as for a
background music application program. Although you cannot directly disable the
active talker feature, you can set the noise level threshhold by which signals are
recognized as either speech or noise.

3.4.2 Audio Conferencing API for Linux Operating Systems

Programming Guide

Update to Section 6.2, “Initialization of DM3 Board Parameters” and to “Active Talker”
chapter (IPY00006584 = PTR 36199)
Changed the description of the MSG_ACTID parameter to indicate that it
enables/disables active talker identification (or notification) and not the active talker
feature itself. Replace the MSG_ACTID parameter with the following:
MSG_ACTID (Active Talker Identification)
Enables or disables Active Talker Identification (or Notification). Possible values are
ACTID_ON or ACTID_OFF. ACTID_ON is the default. This parameter does not enable or